Topics

[Amel Yacht Owners] Hurth Transmissions freewheeling folding prop

James Alton
 

Mike,

   My Maramu has a plate mounted just in front of the shift lever warning to never leave the transmission in Fwd. gear while sailing.  My boat has a fixed 20” (?) 3 blade prop which can produce a large amount of torque when sailing at higher speeds.  I am guessing that since your prop feathers(so produces little torque if any when feathered)  that it may not matter as much which gear you use but apparently due to the design the Reverse gear is stronger and therefore safer to use when locking the prop shaft.  Perhaps others can verify if this would be correct.

   I also read in Foley the these gears seem to last about 1000 hours on average.  The gear on my boat has the same paint as the engine and I don’t see any evidence of it having been replaced.  The engine now has just over 4,000 hours.  Could others comment on the life expectancy the have experienced with the Hurth gears?  My boat appears to have had an aluminum cooler for a very long time,  it may in fact have been original based on the installation.  I replaced the old cooler with a new aluminum one.  The old one was not leaking but when cleaning out the inside I found several pin holes that were only plugged with corrosion so it was overdue.  I just got an email back from Foley saying that they have discontinued selling the stainless coolers and now only sell the aluminum.  I wonder if there were corrosion concerns betwee the aluminum gear case and the stainless coolers.  I will try to find out. 

Best,

James
SV Sueno,  Maramu #220

On Dec 18, 2017, at 11:19 AM, 'Mike Ondra' mdondra@... [amelyachtowners] <amelyachtowners@...> wrote:


Who’d of thought there was so much to know about transmissions and their lubrication! Foley website full of interesting information. On a related topic.

 

Dr. Diesel Tip #101 at Foley says DO NOT put Hurth trans into forward to stop freewheeling, only reverse.

We have always put the trans in forward to stop the freewheeling and fold the Autoprop when under sail. Given Amels have a “C” drive, does Dr. Diesels Tip apply? Have to pose the question just in case there are opinions among our ranks.

 

Mike Ondra

Aletes SM#240

Falmouth Harbor, Antigua

 



David Wallace
 

James, 

Our Hurth 250 started acting up in 2002 with about 6000 hours on the engine. Intermittently it would not go into forward, first discovered when backing out of a slip which made for an interesting evolution. We had it rebuilt with no issue.

Maybe I have a grounding problem on the 4.154 but the aluminum cooler only seems to last a year or two. I now have several, and try to catch the corrosion before it gets to bad. Then I clean up the cooler and rebuild it with aluminum epoxy that I buy from Cotronics. Works really well.

Regards,

Dave
s/v Air Ops
Maramu #104

On Dec 18, 2017, at 7:50 AM, James Alton lokiyawl2@... [amelyachtowners] <amelyachtowners@...> wrote:

Mike,


   My Maramu has a plate mounted just in front of the shift lever warning to never leave the transmission in Fwd. gear while sailing.  My boat has a fixed 20” (?) 3 blade prop which can produce a large amount of torque when sailing at higher speeds.  I am guessing that since your prop feathers(so produces little torque if any when feathered)  that it may not matter as much which gear you use but apparently due to the design the Reverse gear is stronger and therefore safer to use when locking the prop shaft.  Perhaps others can verify if this would be correct.

   I also read in Foley the these gears seem to last about 1000 hours on average.  The gear on my boat has the same paint as the engine and I don’t see any evidence of it having been replaced.  The engine now has just over 4,000 hours.  Could others comment on the life expectancy the have experienced with the Hurth gears?  My boat appears to have had an aluminum cooler for a very long time,  it may in fact have been original based on the installation.  I replaced the old cooler with a new aluminum one.  The old one was not leaking but when cleaning out the inside I found several pin holes that were only plugged with corrosion so it was overdue.  I just got an email back from Foley saying that they have discontinued selling the stainless coolers and now only sell the aluminum.  I wonder if there were corrosion concerns betwee the aluminum gear case and the stainless coolers.  I will try to find out. 

Best,

James
SV Sueno,  Maramu #220

On Dec 18, 2017, at 11:19 AM, 'Mike Ondra' mdondra@... [amelyachtowners] <amelyachtowners@...> wrote:


Who’d of thought there was so much to know about transmissions and their lubrication! Foley website full of interesting information. On a related topic.

 

Dr. Diesel Tip #101 at Foley says DO NOT put Hurth trans into forward to stop freewheeling, only reverse.

We have always put the trans in forward to stop the freewheeling and fold the Autoprop when under sail. Given Amels have a “C” drive, does Dr. Diesels Tip apply? Have to pose the question just in case there are opinions among our ranks.

 

Mike Ondra

Aletes SM#240

Falmouth Harbor, Antigua

 





James Alton
 

Dave,

   Thanks for this information.  At least I now know that at least some of the Hurth 250 transmissions installed on Maramu’s are lasting longer than the 4,000 hours that mine has.  So far my transmission seems to be working fine but the failure mode that you experienced does not sound like a pleasant to experience so maybe I will do something preemptive before long.  

    I have heard of others having a problem with their aluminum coolers corroding quickly as well.  Without being bonded, I would think that the aluminum parts immersed in seawater would become the sacrificial items on the engine so maybe that could be part of your problem as you suspect.  I am wondering however if there is more than one manufacturer of these coolers with some being made of a more corrosion resistant alloy?  The original cooler on my transmission had a plate on it that in large letters had the name Hurth,  Monchen,  Made in West Germany.  The old rusty hose clamps, hoses and the apparent age of the ID plate and mounting bolts suggests to me that this cooler had been on the transmission for a very long time.  The one that I ordered as a replacement and installed this year with all new hoses was sold by “Mr Cool” 3306107001 ZF Transmission/Gear Cooler.  The replacement cooler cost $165.00 USD.  The Cooler being sold by Foley is much more expensive,  $395.00 which comes with a quart of their special synthetic fluid. I think I will inquire and see what they say about the large cost differential.    Can you tell me where you have been buying your coolers?

    In part over corrosion concerns for my cooler, I have been flushing the engine with fresh water whenever the engine will sit for more than a couple of days which I think should help to reduce the corrosion some.   I think that I will open the cooler at least every couple of seasons to see how much corrosion is present.  

Best,

James  Alton
SV Sueno,  #220
Arbatax,  Italy

On Dec 18, 2017, at 8:32 PM, David Wallace svairops@... [amelyachtowners] <amelyachtowners@...> wrote:

James, 


Our Hurth 250 started acting up in 2002 with about 6000 hours on the engine. Intermittently it would not go into forward, first discovered when backing out of a slip which made for an interesting evolution. We had it rebuilt with no issue.

Maybe I have a grounding problem on the 4.154 but the aluminum cooler only seems to last a year or two. I now have several, and try to catch the corrosion before it gets to bad. Then I clean up the cooler and rebuild it with aluminum epoxy that I buy from Cotronics. Works really well.

Regards,

Dave
s/v Air Ops
Maramu #104

On Dec 18, 2017, at 7:50 AM, James Alton lokiyawl2@... [amelyachtowners] <amelyachtowners@...> wrote:

Mike,


   My Maramu has a plate mounted just in front of the shift lever warning to never leave the transmission in Fwd. gear while sailing.  My boat has a fixed 20” (?) 3 blade prop which can produce a large amount of torque when sailing at higher speeds.  I am guessing that since your prop feathers(so produces little torque if any when feathered)  that it may not matter as much which gear you use but apparently due to the design the Reverse gear is stronger and therefore safer to use when locking the prop shaft.  Perhaps others can verify if this would be correct.

   I also read in Foley the these gears seem to last about 1000 hours on average.  The gear on my boat has the same paint as the engine and I don’t see any evidence of it having been replaced.  The engine now has just over 4,000 hours.  Could others comment on the life expectancy the have experienced with the Hurth gears?  My boat appears to have had an aluminum cooler for a very long time,  it may in fact have been original based on the installation.  I replaced the old cooler with a new aluminum one.  The old one was not leaking but when cleaning out the inside I found several pin holes that were only plugged with corrosion so it was overdue.  I just got an email back from Foley saying that they have discontinued selling the stainless coolers and now only sell the aluminum.  I wonder if there were corrosion concerns betwee the aluminum gear case and the stainless coolers.  I will try to find out. 

Best,

James
SV Sueno,  Maramu #220

On Dec 18, 2017, at 11:19 AM, 'Mike Ondra' mdondra@... [amelyachtowners] <amelyachtowners@...> wrote:


Who’d of thought there was so much to know about transmissions and their lubrication! Foley website full of interesting information. On a related topic.

 

Dr. Diesel Tip #101 at Foley says DO NOT put Hurth trans into forward to stop freewheeling, only reverse.

We have always put the trans in forward to stop the freewheeling and fold the Autoprop when under sail. Given Amels have a “C” drive, does Dr. Diesels Tip apply? Have to pose the question just in case there are opinions among our ranks.

 

Mike Ondra

Aletes SM#240

Falmouth Harbor, Antigua

 







Bill & Judy Rouse <yahoogroups@...>
 

Dave,

It sounds like you have a bonding problem which may cause you serious issues. I am going to send you a page out of my book which will allow you to test the bonding of the engine to the zincs when in the water. 

Every owner should check continuity between the prop and the zincs each time you haul out. Using the resistance setting on a multitester with a long piece of wire to extend one probe to the the prop with the other probe on the zinc, the multitester should read very little to zero resistance...in other words there should be close to 100% continuity. 

If there is continuity, you can be assured that your rudder post, prop, C-Drive or shaft, transmission, and engine are protected. Of course, this assumes that everything between your prop and engine are connected metal-to-metal.


CW Bill Rouse
Admiral, Texas Navy
Commander Emeritus
Amel School www.amelschool.com
720 Winnie St
Galveston Island, TX 77550
+1(832) 380-4970

   


On Dec 18, 2017 18:32, "David Wallace svairops@... [amelyachtowners]" <amelyachtowners@...> wrote:
 

James, 


Our Hurth 250 started acting up in 2002 with about 6000 hours on the engine. Intermittently it would not go into forward, first discovered when backing out of a slip which made for an interesting evolution. We had it rebuilt with no issue.

Maybe I have a grounding problem on the 4.154 but the aluminum cooler only seems to last a year or two. I now have several, and try to catch the corrosion before it gets to bad. Then I clean up the cooler and rebuild it with aluminum epoxy that I buy from Cotronics. Works really well.

Regards,

Dave
s/v Air Ops
Maramu #104

On Dec 18, 2017, at 7:50 AM, James Alton lokiyawl2@... [amelyachtowners] <amelyachtowners@yahoogroups.com> wrote:

Mike,


   My Maramu has a plate mounted just in front of the shift lever warning to never leave the transmission in Fwd. gear while sailing.  My boat has a fixed 20” (?) 3 blade prop which can produce a large amount of torque when sailing at higher speeds.  I am guessing that since your prop feathers(so produces little torque if any when feathered)  that it may not matter as much which gear you use but apparently due to the design the Reverse gear is stronger and therefore safer to use when locking the prop shaft.  Perhaps others can verify if this would be correct.

   I also read in Foley the these gears seem to last about 1000 hours on average.  The gear on my boat has the same paint as the engine and I don’t see any evidence of it having been replaced.  The engine now has just over 4,000 hours.  Could others comment on the life expectancy the have experienced with the Hurth gears?  My boat appears to have had an aluminum cooler for a very long time,  it may in fact have been original based on the installation.  I replaced the old cooler with a new aluminum one.  The old one was not leaking but when cleaning out the inside I found several pin holes that were only plugged with corrosion so it was overdue.  I just got an email back from Foley saying that they have discontinued selling the stainless coolers and now only sell the aluminum.  I wonder if there were corrosion concerns betwee the aluminum gear case and the stainless coolers.  I will try to find out. 

Best,

James
SV Sueno,  Maramu #220

On Dec 18, 2017, at 11:19 AM, 'Mike Ondra' mdondra@... [amelyachtowners] <amelyachtowners@yahoogroups.com> wrote:


Who’d of thought there was so much to know about transmissions and their lubrication! Foley website full of interesting information. On a related topic.

 

Dr. Diesel Tip #101 at Foley says DO NOT put Hurth trans into forward to stop freewheeling, only reverse.

We have always put the trans in forward to stop the freewheeling and fold the Autoprop when under sail. Given Amels have a “C” drive, does Dr. Diesels Tip apply? Have to pose the question just in case there are opinions among our ranks.

 

Mike Ondra

Aletes SM#240

Falmouth Harbor, Antigua

 






svsunnyside
 

James

I can confirm you that the Hurth 250 transmission can work much more than 4,000 hours. Mine passed 10,000 hours and , still now, never gave me a problem.

Best

Gabriele Antolini
SV Sunny Side 
Maramu #219
Todomar Yard Cartagena



From: "James Alton lokiyawl2@... [amelyachtowners]"
To: amelyachtowners@...
Sent: Monday, 18 December 2017, 23:42
Subject: Re: [Amel Yacht Owners] Hurth Transmissions freewheeling folding prop

 
Dave,

   Thanks for this information.  At least I now know that at least some of the Hurth 250 transmissions installed on Maramu’s are lasting longer than the 4,000 hours that mine has.  So far my transmission seems to be working fine but the failure mode that you experienced does not sound like a pleasant to experience so maybe I will do something preemptive before long.  

    I have heard of others having a problem with their aluminum coolers corroding quickly as well..  Without being bonded, I would think that the aluminum parts immersed in seawater would become the sacrificial items on the engine so maybe that could be part of your problem as you suspect.  I am wondering however if there is more than one manufacturer of these coolers with some being made of a more corrosion resistant alloy?  The original cooler on my transmission had a plate on it that in large letters had the name Hurth,  Monchen,  Made in West Germany.  The old rusty hose clamps, hoses and the apparent age of the ID plate and mounting bolts suggests to me that this cooler had been on the transmission for a very long time.  The one that I ordered as a replacement and installed this year with all new hoses was sold by “Mr Cool” 3306107001 ZF Transmission/Gear Cooler.  The replacement cooler cost $165.00 USD.  The Cooler being sold by Foley is much more expensive,  $395.00 which comes with a quart of their special synthetic fluid. I think I will inquire and see what they say about the large cost differential.    Can you tell me where you have been buying your coolers?

    In part over corrosion concerns for my cooler, I have been flushing the engine with fresh water whenever the engine will sit for more than a couple of days which I think should help to reduce the corrosion some.   I think that I will open the cooler at least every couple of seasons to see how much corrosion is present.  

Best,

James  Alton
SV Sueno,  #220
Arbatax,  Italy

On Dec 18, 2017, at 8:32 PM, David Wallace svairops@... [amelyachtowners] <amelyachtowners@...> wrote:

James, 

Our Hurth 250 started acting up in 2002 with about 6000 hours on the engine. Intermittently it would not go into forward, first discovered when backing out of a slip which made for an interesting evolution. We had it rebuilt with no issue.

Maybe I have a grounding problem on the 4.154 but the aluminum cooler only seems to last a year or two. I now have several, and try to catch the corrosion before it gets to bad. Then I clean up the cooler and rebuild it with aluminum epoxy that I buy from Cotronics. Works really well.

Regards,

Dave
s/v Air Ops
Maramu #104

On Dec 18, 2017, at 7:50 AM, James Alton lokiyawl2@... [amelyachtowners] <amelyachtowners@...> wrote:

Mike,

   My Maramu has a plate mounted just in front of the shift lever warning to never leave the transmission in Fwd. gear while sailing.  My boat has a fixed 20” (?) 3 blade prop which can produce a large amount of torque when sailing at higher speeds.  I am guessing that since your prop feathers(so produces little torque if any when feathered)  that it may not matter as much which gear you use but apparently due to the design the Reverse gear is stronger and therefore safer to use when locking the prop shaft.  Perhaps others can verify if this would be correct.

   I also read in Foley the these gears seem to last about 1000 hours on average.  The gear on my boat has the same paint as the engine and I don’t see any evidence of it having been replaced.  The engine now has just over 4,000 hours.  Could others comment on the life expectancy the have experienced with the Hurth gears?  My boat appears to have had an aluminum cooler for a very long time,  it may in fact have been original based on the installation.  I replaced the old cooler with a new aluminum one.  The old one was not leaking but when cleaning out the inside I found several pin holes that were only plugged with corrosion so it was overdue.  I just got an email back from Foley saying that they have discontinued selling the stainless coolers and now only sell the aluminum.  I wonder if there were corrosion concerns betwee the aluminum gear case and the stainless coolers.  I will try to find out. 

Best,

James
SV Sueno,  Maramu #220

On Dec 18, 2017, at 11:19 AM, 'Mike Ondra' mdondra@... [amelyachtowners] <amelyachtowners@...> wrote:


Who’d of thought there was so much to know about transmissions and their lubrication! Foley website full of interesting information. On a related topic..
 
Dr. Diesel Tip #101 at Foley says DO NOT put Hurth trans into forward to stop freewheeling, only reverse.
We have always put the trans in forward to stop the freewheeling and fold the Autoprop when under sail. Given Amels have a “C” drive, does Dr. Diesels Tip apply? Have to pose the question just in case there are opinions among our ranks.
 
Mike Ondra
Aletes SM#240
Falmouth Harbor, Antigua
 








James Alton
 

Gabriele Anolini,

   That is amazing,  you must be taking exceptional care of your transmission.  Do you have a cooler on your transmission?  Foley seems to be saying that 1000 hours is about all that we should expect.  It would be nice to know which factors seem to lead to a longer service life.   

Happy Holidays,

James

SV Sueno
Maramu #220

On Dec 19, 2017, at 11:25 AM, Gabriele Antolini svsunnyside@... [amelyachtowners] <amelyachtowners@...> wrote:


James

I can confirm you that the Hurth 250 transmission can work much more than 4,000 hours. Mine passed 10,000 hours and , still now, never gave me a problem.

Best

Gabriele Antolini
SV Sunny Side 
Maramu #219
Todomar Yard Cartagena



From: "James Alton lokiyawl2@... [amelyachtowners]" <amelyachtowners@...>
To: amelyachtowners@... 
Sent: Monday, 18 December 2017, 23:42
Subject: Re: [Amel Yacht Owners] Hurth Transmissions freewheeling folding prop

 
Dave,

   Thanks for this information.  At least I now know that at least some of the Hurth 250 transmissions installed on Maramu’s are lasting longer than the 4,000 hours that mine has.  So far my transmission seems to be working fine but the failure mode that you experienced does not sound like a pleasant to experience so maybe I will do something preemptive before long.  

    I have heard of others having a problem with their aluminum coolers corroding quickly as well..  Without being bonded, I would think that the aluminum parts immersed in seawater would become the sacrificial items on the engine so maybe that could be part of your problem as you suspect.  I am wondering however if there is more than one manufacturer of these coolers with some being made of a more corrosion resistant alloy?  The original cooler on my transmission had a plate on it that in large letters had the name Hurth,  Monchen,  Made in West Germany.  The old rusty hose clamps, hoses and the apparent age of the ID plate and mounting bolts suggests to me that this cooler had been on the transmission for a very long time.  The one that I ordered as a replacement and installed this year with all new hoses was sold by “Mr Cool” 3306107001 ZF Transmission/Gear Cooler.  The replacement cooler cost $165.00 USD.  The Cooler being sold by Foley is much more expensive,  $395.00 which comes with a quart of their special synthetic fluid. I think I will inquire and see what they say about the large cost differential.    Can you tell me where you have been buying your coolers?

    In part over corrosion concerns for my cooler, I have been flushing the engine with fresh water whenever the engine will sit for more than a couple of days which I think should help to reduce the corrosion some.   I think that I will open the cooler at least every couple of seasons to see how much corrosion is present.  

Best,

James  Alton
SV Sueno,  #220
Arbatax,  Italy

On Dec 18, 2017, at 8:32 PM, David Wallace svairops@... [amelyachtowners] <amelyachtowners@...> wrote:

James, 

Our Hurth 250 started acting up in 2002 with about 6000 hours on the engine. Intermittently it would not go into forward, first discovered when backing out of a slip which made for an interesting evolution. We had it rebuilt with no issue.

Maybe I have a grounding problem on the 4.154 but the aluminum cooler only seems to last a year or two. I now have several, and try to catch the corrosion before it gets to bad. Then I clean up the cooler and rebuild it with aluminum epoxy that I buy from Cotronics. Works really well.

Regards,

Dave
s/v Air Ops
Maramu #104

On Dec 18, 2017, at 7:50 AM, James Alton lokiyawl2@... [amelyachtowners] <amelyachtowners@...> wrote:

Mike,

   My Maramu has a plate mounted just in front of the shift lever warning to never leave the transmission in Fwd. gear while sailing.  My boat has a fixed 20” (?) 3 blade prop which can produce a large amount of torque when sailing at higher speeds.  I am guessing that since your prop feathers(so produces little torque if any when feathered)  that it may not matter as much which gear you use but apparently due to the design the Reverse gear is stronger and therefore safer to use when locking the prop shaft.  Perhaps others can verify if this would be correct.

   I also read in Foley the these gears seem to last about 1000 hours on average.  The gear on my boat has the same paint as the engine and I don’t see any evidence of it having been replaced.  The engine now has just over 4,000 hours.  Could others comment on the life expectancy the have experienced with the Hurth gears?  My boat appears to have had an aluminum cooler for a very long time,  it may in fact have been original based on the installation.  I replaced the old cooler with a new aluminum one.  The old one was not leaking but when cleaning out the inside I found several pin holes that were only plugged with corrosion so it was overdue.  I just got an email back from Foley saying that they have discontinued selling the stainless coolers and now only sell the aluminum.  I wonder if there were corrosion concerns betwee the aluminum gear case and the stainless coolers.  I will try to find out. 

Best,

James
SV Sueno,  Maramu #220

On Dec 18, 2017, at 11:19 AM, 'Mike Ondra' mdondra@... [amelyachtowners] <amelyachtowners@...> wrote:


Who’d of thought there was so much to know about transmissions and their lubrication! Foley website full of interesting information. On a related topic..
 
Dr. Diesel Tip #101 at Foley says DO NOT put Hurth trans into forward to stop freewheeling, only reverse.
We have always put the trans in forward to stop the freewheeling and fold the Autoprop when under sail. Given Amels have a “C” drive, does Dr. Diesels Tip apply? Have to pose the question just in case there are opinions among our ranks.
 
Mike Ondra
Aletes SM#240
Falmouth Harbor, Antigua
 










David Wallace
 

Bill, 

I really appreciate your sending the testing procedure (I received that separately, thanks!). We will be hauling in Jan or Feb for bottom painting so the opportunity is at hand to check the continuity. We do keep track of the condition of the rudder zincs, and do have a zinc on the shaft, as well as on the MaxProp. As a side note, in 2007 when we had the engine out for a rebuild I pulled the shaft for inspection. There was no corrosion but some scoring so replaced it given the opportunity to do so easily.

Thanks again for your help. You continue to be a truly excellent resource for all of us Amel owners!

Dave Wallace
s/v Air Ops
Maramu #104
Puerto Escondido, BCS, Mx

On Dec 19, 2017, at 6:11 AM, 'Bill & Judy Rouse' yahoogroups@... [amelyachtowners] <amelyachtowners@...> wrote:


Dave,

It sounds like you have a bonding problem which may cause you serious issues. I am going to send you a page out of my book which will allow you to test the bonding of the engine to the zincs when in the water. 

Every owner should check continuity between the prop and the zincs each time you haul out. Using the resistance setting on a multitester with a long piece of wire to extend one probe to the the prop with the other probe on the zinc, the multitester should read very little to zero resistance...in other words there should be close to 100% continuity. 

If there is continuity, you can be assured that your rudder post, prop, C-Drive or shaft, transmission, and engine are protected. Of course, this assumes that everything between your prop and engine are connected metal-to-metal.


CW Bill Rouse
Admiral, Texas Navy
Commander Emeritus
Amel School www.amelschool.com
720 Winnie St
Galveston Island, TX 77550
+1(832) 380-4970

   


On Dec 18, 2017 18:32, "David Wallace svairops@... [amelyachtowners]" <amelyachtowners@...> wrote:
 

James, 


Our Hurth 250 started acting up in 2002 with about 6000 hours on the engine. Intermittently it would not go into forward, first discovered when backing out of a slip which made for an interesting evolution. We had it rebuilt with no issue.

Maybe I have a grounding problem on the 4.154 but the aluminum cooler only seems to last a year or two. I now have several, and try to catch the corrosion before it gets to bad. Then I clean up the cooler and rebuild it with aluminum epoxy that I buy from Cotronics. Works really well.

Regards,

Dave
s/v Air Ops
Maramu #104

On Dec 18, 2017, at 7:50 AM, James Alton lokiyawl2@... [amelyachtowners] <amelyachtowners@yahoogroups.com> wrote:

Mike,


   My Maramu has a plate mounted just in front of the shift lever warning to never leave the transmission in Fwd. gear while sailing.  My boat has a fixed 20” (?) 3 blade prop which can produce a large amount of torque when sailing at higher speeds.  I am guessing that since your prop feathers(so produces little torque if any when feathered)  that it may not matter as much which gear you use but apparently due to the design the Reverse gear is stronger and therefore safer to use when locking the prop shaft.  Perhaps others can verify if this would be correct.

   I also read in Foley the these gears seem to last about 1000 hours on average.  The gear on my boat has the same paint as the engine and I don’t see any evidence of it having been replaced.  The engine now has just over 4,000 hours.  Could others comment on the life expectancy the have experienced with the Hurth gears?  My boat appears to have had an aluminum cooler for a very long time,  it may in fact have been original based on the installation.  I replaced the old cooler with a new aluminum one.  The old one was not leaking but when cleaning out the inside I found several pin holes that were only plugged with corrosion so it was overdue.  I just got an email back from Foley saying that they have discontinued selling the stainless coolers and now only sell the aluminum.  I wonder if there were corrosion concerns betwee the aluminum gear case and the stainless coolers.  I will try to find out. 

Best,

James
SV Sueno,  Maramu #220

On Dec 18, 2017, at 11:19 AM, 'Mike Ondra' mdondra@... [amelyachtowners] <amelyachtowners@yahoogroups.com> wrote:


Who’d of thought there was so much to know about transmissions and their lubrication! Foley website full of interesting information. On a related topic.

 

Dr. Diesel Tip #101 at Foley says DO NOT put Hurth trans into forward to stop freewheeling, only reverse.

We have always put the trans in forward to stop the freewheeling and fold the Autoprop when under sail. Given Amels have a “C” drive, does Dr. Diesels Tip apply? Have to pose the question just in case there are opinions among our ranks.

 

Mike Ondra

Aletes SM#240

Falmouth Harbor, Antigua

 









David Wallace
 

James,

I have one of those plates as well. Interestingly, the plates, old and new, never seem to corrode much, just the box itself. The most worrisome corrosion is to the pipes that the hoses are clamped on — obviously there would be a major problem if one of those failed. So the box and hose connections are part of my engine room check list I go through every time prior to starting the engine. And I also flush the engine with fresh water when we lay up the boat for more than a couple of weeks.

My source for the cooler box has been Trans Atlantic Diesel (www.tadiesels.com), located in Virginia. Like Foley, they specialize in Perkins and have been very helpful in providing parts for the old 4.154. I think their price for the cooler box is about what you paid.

Best regards,

Dave
s/v Air Ops
Maramu #104
Puerto Escondido, BCS, Mx

On Dec 18, 2017, at 7:42 PM, James Alton lokiyawl2@... [amelyachtowners] <amelyachtowners@...> wrote:

Dave,


   Thanks for this information.  At least I now know that at least some of the Hurth 250 transmissions installed on Maramu’s are lasting longer than the 4,000 hours that mine has.  So far my transmission seems to be working fine but the failure mode that you experienced does not sound like a pleasant to experience so maybe I will do something preemptive before long.  

    I have heard of others having a problem with their aluminum coolers corroding quickly as well..  Without being bonded, I would think that the aluminum parts immersed in seawater would become the sacrificial items on the engine so maybe that could be part of your problem as you suspect.  I am wondering however if there is more than one manufacturer of these coolers with some being made of a more corrosion resistant alloy?  The original cooler on my transmission had a plate on it that in large letters had the name Hurth,  Monchen,  Made in West Germany.  The old rusty hose clamps, hoses and the apparent age of the ID plate and mounting bolts suggests to me that this cooler had been on the transmission for a very long time.  The one that I ordered as a replacement and installed this year with all new hoses was sold by “Mr Cool” 3306107001 ZF Transmission/Gear Cooler.  The replacement cooler cost $165.00 USD.  The Cooler being sold by Foley is much more expensive,  $395.00 which comes with a quart of their special synthetic fluid. I think I will inquire and see what they say about the large cost differential.    Can you tell me where you have been buying your coolers?

    In part over corrosion concerns for my cooler, I have been flushing the engine with fresh water whenever the engine will sit for more than a couple of days which I think should help to reduce the corrosion some.   I think that I will open the cooler at least every couple of seasons to see how much corrosion is present.  

Best,

James  Alton
SV Sueno,  #220
Arbatax,  Italy

On Dec 18, 2017, at 8:32 PM, David Wallace svairops@... [amelyachtowners] <amelyachtowners@...> wrote:

James, 


Our Hurth 250 started acting up in 2002 with about 6000 hours on the engine. Intermittently it would not go into forward, first discovered when backing out of a slip which made for an interesting evolution. We had it rebuilt with no issue.

Maybe I have a grounding problem on the 4.154 but the aluminum cooler only seems to last a year or two. I now have several, and try to catch the corrosion before it gets to bad. Then I clean up the cooler and rebuild it with aluminum epoxy that I buy from Cotronics. Works really well.

Regards,

Dave
s/v Air Ops
Maramu #104

On Dec 18, 2017, at 7:50 AM, James Alton lokiyawl2@... [amelyachtowners] <amelyachtowners@...> wrote:

Mike,


   My Maramu has a plate mounted just in front of the shift lever warning to never leave the transmission in Fwd. gear while sailing.  My boat has a fixed 20” (?) 3 blade prop which can produce a large amount of torque when sailing at higher speeds.  I am guessing that since your prop feathers(so produces little torque if any when feathered)  that it may not matter as much which gear you use but apparently due to the design the Reverse gear is stronger and therefore safer to use when locking the prop shaft.  Perhaps others can verify if this would be correct.

   I also read in Foley the these gears seem to last about 1000 hours on average.  The gear on my boat has the same paint as the engine and I don’t see any evidence of it having been replaced.  The engine now has just over 4,000 hours.  Could others comment on the life expectancy the have experienced with the Hurth gears?  My boat appears to have had an aluminum cooler for a very long time,  it may in fact have been original based on the installation.  I replaced the old cooler with a new aluminum one.  The old one was not leaking but when cleaning out the inside I found several pin holes that were only plugged with corrosion so it was overdue.  I just got an email back from Foley saying that they have discontinued selling the stainless coolers and now only sell the aluminum.  I wonder if there were corrosion concerns betwee the aluminum gear case and the stainless coolers.  I will try to find out. 

Best,

James
SV Sueno,  Maramu #220

On Dec 18, 2017, at 11:19 AM, 'Mike Ondra' mdondra@... [amelyachtowners] <amelyachtowners@...> wrote:


Who’d of thought there was so much to know about transmissions and their lubrication! Foley website full of interesting information. On a related topic..

 

Dr. Diesel Tip #101 at Foley says DO NOT put Hurth trans into forward to stop freewheeling, only reverse.

We have always put the trans in forward to stop the freewheeling and fold the Autoprop when under sail. Given Amels have a “C” drive, does Dr. Diesels Tip apply? Have to pose the question just in case there are opinions among our ranks.

 

Mike Ondra

Aletes SM#240

Falmouth Harbor, Antigua

 









svsunnyside
 

Hi James
 - Good care : YES  ,  Exceptional care: I do not think so. The only thing I use ,  that not everyone use ,  is:  MILITEC-1 (everywhere possible, on sea and on land) according to the producer recommendations . Nothing to do with the cooler.
 - Cooler  : Yes I have the small square aluminum cooler. I changed it on 97 . when I received the boat, with 4,000 hours.
From 99 to 2006 I was living on board using marinas only when could not be evitable. In the last ten years, at the end of my four months sailing season, in April, I ran the engine for one hour with fresh water(half an hour one day and half an hour, one day or two later) . 
A little of luck is always welcome. 

Gabriele
SV Sunny Side
Maramu #219


From: "James Alton lokiyawl2@... [amelyachtowners]"
To: amelyachtowners@...
Sent: Tuesday, 19 December 2017, 12:06
Subject: Re: [Amel Yacht Owners] Hurth Transmissions freewheeling folding prop

 
Gabriele Anolini,

   That is amazing,  you must be taking exceptional care of your transmission.  Do you have a cooler on your transmission?  Foley seems to be saying that 1000 hours is about all that we should expect.  It would be nice to know which factors seem to lead to a longer service life.   

Happy Holidays,

James

SV Sueno
Maramu #220

On Dec 19, 2017, at 11:25 AM, Gabriele Antolini svsunnyside@... [amelyachtowners] <amelyachtowners@...> wrote:


James

I can confirm you that the Hurth 250 transmission can work much more than 4,000 hours. Mine passed 10,000 hours and , still now, never gave me a problem.

Best

Gabriele Antolini
SV Sunny Side 
Maramu #219
Todomar Yard Cartagena



From: "James Alton lokiyawl2@... [amelyachtowners]" <amelyachtowners@...>
To: amelyachtowners@... 
Sent: Monday, 18 December 2017, 23:42
Subject: Re: [Amel Yacht Owners] Hurth Transmissions freewheeling folding prop

 
Dave,

   Thanks for this information.  At least I now know that at least some of the Hurth 250 transmissions installed on Maramu’s are lasting longer than the 4,000 hours that mine has.  So far my transmission seems to be working fine but the failure mode that you experienced does not sound like a pleasant to experience so maybe I will do something preemptive before long.  

    I have heard of others having a problem with their aluminum coolers corroding quickly as well..  Without being bonded, I would think that the aluminum parts immersed in seawater would become the sacrificial items on the engine so maybe that could be part of your problem as you suspect.  I am wondering however if there is more than one manufacturer of these coolers with some being made of a more corrosion resistant alloy?  The original cooler on my transmission had a plate on it that in large letters had the name Hurth,  Monchen,  Made in West Germany.  The old rusty hose clamps, hoses and the apparent age of the ID plate and mounting bolts suggests to me that this cooler had been on the transmission for a very long time.  The one that I ordered as a replacement and installed this year with all new hoses was sold by “Mr Cool” 3306107001 ZF Transmission/Gear Cooler.  The replacement cooler cost $165.00 USD.  The Cooler being sold by Foley is much more expensive,  $395.00 which comes with a quart of their special synthetic fluid. I think I will inquire and see what they say about the large cost differential.    Can you tell me where you have been buying your coolers?

    In part over corrosion concerns for my cooler, I have been flushing the engine with fresh water whenever the engine will sit for more than a couple of days which I think should help to reduce the corrosion some.   I think that I will open the cooler at least every couple of seasons to see how much corrosion is present.  

Best,

James  Alton
SV Sueno,  #220
Arbatax,  Italy

On Dec 18, 2017, at 8:32 PM, David Wallace svairops@hotmail..com [amelyachtowners] <amelyachtowners@...> wrote:

James, 

Our Hurth 250 started acting up in 2002 with about 6000 hours on the engine. Intermittently it would not go into forward, first discovered when backing out of a slip which made for an interesting evolution. We had it rebuilt with no issue.

Maybe I have a grounding problem on the 4.154 but the aluminum cooler only seems to last a year or two. I now have several, and try to catch the corrosion before it gets to bad. Then I clean up the cooler and rebuild it with aluminum epoxy that I buy from Cotronics. Works really well.

Regards,

Dave
s/v Air Ops
Maramu #104

On Dec 18, 2017, at 7:50 AM, James Alton lokiyawl2@... [amelyachtowners] <amelyachtowners@...> wrote:

Mike,

   My Maramu has a plate mounted just in front of the shift lever warning to never leave the transmission in Fwd. gear while sailing.  My boat has a fixed 20” (?) 3 blade prop which can produce a large amount of torque when sailing at higher speeds.  I am guessing that since your prop feathers(so produces little torque if any when feathered)  that it may not matter as much which gear you use but apparently due to the design the Reverse gear is stronger and therefore safer to use when locking the prop shaft.  Perhaps others can verify if this would be correct.

   I also read in Foley the these gears seem to last about 1000 hours on average.  The gear on my boat has the same paint as the engine and I don’t see any evidence of it having been replaced.  The engine now has just over 4,000 hours.  Could others comment on the life expectancy the have experienced with the Hurth gears?  My boat appears to have had an aluminum cooler for a very long time,  it may in fact have been original based on the installation.  I replaced the old cooler with a new aluminum one.  The old one was not leaking but when cleaning out the inside I found several pin holes that were only plugged with corrosion so it was overdue.  I just got an email back from Foley saying that they have discontinued selling the stainless coolers and now only sell the aluminum.  I wonder if there were corrosion concerns betwee the aluminum gear case and the stainless coolers.  I will try to find out. 

Best,

James
SV Sueno,  Maramu #220

On Dec 18, 2017, at 11:19 AM, 'Mike Ondra' mdondra@... [amelyachtowners] <amelyachtowners@...> wrote:


Who’d of thought there was so much to know about transmissions and their lubrication! Foley website full of interesting information. On a related topic..
 
Dr. Diesel Tip #101 at Foley says DO NOT put Hurth trans into forward to stop freewheeling, only reverse.
We have always put the trans in forward to stop the freewheeling and fold the Autoprop when under sail. Given Amels have a “C” drive, does Dr. Diesels Tip apply? Have to pose the question just in case there are opinions among our ranks.
 
Mike Ondra
Aletes SM#240
Falmouth Harbor, Antigua
 












eric freedman
 

James,

I have about 6000 miles on mine.

Fair Winds

Eric

Kimberlite Amel Super Maramu #376

 

 

From: amelyachtowners@... [mailto:amelyachtowners@...]
Sent: Tuesday, December 19, 2017 10:54 AM
To: amelyachtowners@...
Subject: Re: [Amel Yacht Owners] Hurth Transmissions freewheeling folding prop

 

 

Gabriele Anolini,

 

   That is amazing,  you must be taking exceptional care of your transmission.  Do you have a cooler on your transmission?  Foley seems to be saying that 1000 hours is about all that we should expect.  It would be nice to know which factors seem to lead to a longer service life.   

 

Happy Holidays,

 

James

 

SV Sueno

Maramu #220

 

On Dec 19, 2017, at 11:25 AM, Gabriele Antolini svsunnyside@... [amelyachtowners] <amelyachtowners@...> wrote:

 

 

James

 

I can confirm you that the Hurth 250 transmission can work much more than 4,000 hours. Mine passed 10,000 hours and , still now, never gave me a problem.

 

Best

 

Gabriele Antolini

SV Sunny Side 

Maramu #219

Todomar Yard Cartagena

 


From: "James Alton lokiyawl2@... [amelyachtowners]" <amelyachtowners@...>
To: amelyachtowners@... 
Sent: Monday, 18 December 2017, 23:42
Subject: Re: [Amel Yacht Owners] Hurth Transmissions freewheeling folding prop

 

 

Dave,

 

   Thanks for this information.  At least I now know that at least some of the Hurth 250 transmissions installed on Maramu’s are lasting longer than the 4,000 hours that mine has.  So far my transmission seems to be working fine but the failure mode that you experienced does not sound like a pleasant to experience so maybe I will do something preemptive before long.  

 

    I have heard of others having a problem with their aluminum coolers corroding quickly as well..  Without being bonded, I would think that the aluminum parts immersed in seawater would become the sacrificial items on the engine so maybe that could be part of your problem as you suspect.  I am wondering however if there is more than one manufacturer of these coolers with some being made of a more corrosion resistant alloy?  The original cooler on my transmission had a plate on it that in large letters had the name Hurth,  Monchen,  Made in West Germany.  The old rusty hose clamps, hoses and the apparent age of the ID plate and mounting bolts suggests to me that this cooler had been on the transmission for a very long time.  The one that I ordered as a replacement and installed this year with all new hoses was sold by “Mr Cool” 3306107001 ZF Transmission/Gear Cooler.  The replacement cooler cost $165.00 USD.  The Cooler being sold by Foley is much more expensive,  $395.00 which comes with a quart of their special synthetic fluid. I think I will inquire and see what they say about the large cost differential.    Can you tell me where you have been buying your coolers?

 

    In part over corrosion concerns for my cooler, I have been flushing the engine with fresh water whenever the engine will sit for more than a couple of days which I think should help to reduce the corrosion some.   I think that I will open the cooler at least every couple of seasons to see how much corrosion is present.  

 

Best,

 

James  Alton

SV Sueno,  #220

Arbatax,  Italy

 

On Dec 18, 2017, at 8:32 PM, David Wallace svairops@hotmail..com [amelyachtowners] <amelyachtowners@...> wrote:

 

James, 

 

Our Hurth 250 started acting up in 2002 with about 6000 hours on the engine. Intermittently it would not go into forward, first discovered when backing out of a slip which made for an interesting evolution. We had it rebuilt with no issue.

 

Maybe I have a grounding problem on the 4.154 but the aluminum cooler only seems to last a year or two. I now have several, and try to catch the corrosion before it gets to bad. Then I clean up the cooler and rebuild it with aluminum epoxy that I buy from Cotronics. Works really well.

 

Regards,

 

Dave

s/v Air Ops

Maramu #104

 

On Dec 18, 2017, at 7:50 AM, James Alton lokiyawl2@... [amelyachtowners] <amelyachtowners@...> wrote:



Mike,

 

   My Maramu has a plate mounted just in front of the shift lever warning to never leave the transmission in Fwd. gear while sailing.  My boat has a fixed 20” (?) 3 blade prop which can produce a large amount of torque when sailing at higher speeds.  I am guessing that since your prop feathers(so produces little torque if any when feathered)  that it may not matter as much which gear you use but apparently due to the design the Reverse gear is stronger and therefore safer to use when locking the prop shaft.  Perhaps others can verify if this would be correct.

 

   I also read in Foley the these gears seem to last about 1000 hours on average.  The gear on my boat has the same paint as the engine and I don’t see any evidence of it having been replaced.  The engine now has just over 4,000 hours.  Could others comment on the life expectancy the have experienced with the Hurth gears?  My boat appears to have had an aluminum cooler for a very long time,  it may in fact have been original based on the installation.  I replaced the old cooler with a new aluminum one.  The old one was not leaking but when cleaning out the inside I found several pin holes that were only plugged with corrosion so it was overdue.  I just got an email back from Foley saying that they have discontinued selling the stainless coolers and now only sell the aluminum.  I wonder if there were corrosion concerns betwee the aluminum gear case and the stainless coolers.  I will try to find out. 

 

Best,

 

James

SV Sueno,  Maramu #220

 

On Dec 18, 2017, at 11:19 AM, 'Mike Ondra' mdondra@... [amelyachtowners] <amelyachtowners@...> wrote:

 

 

Who’d of thought there was so much to know about transmissions and their lubrication! Foley website full of interesting information. On a related topic..

 

Dr. Diesel Tip #101 at Foley says DO NOT put Hurth trans into forward to stop freewheeling, only reverse.

We have always put the trans in forward to stop the freewheeling and fold the Autoprop when under sail. Given Amels have a “C” drive, does Dr. Diesels Tip apply? Have to pose the question just in case there are opinions among our ranks.

 

Mike Ondra

Aletes SM#240

Falmouth Harbor, Antigua

 

 

 

 

 

 

 

 

 

 

James Alton
 

Hi Eric,

Did you mean to type 6000 hours or miles?

Best,

James
SV Sueno, Maramu #220

On Dec 19, 2017, at 5:27 PM, 'sailormon' kimberlite@... [amelyachtowners] <amelyachtowners@...> wrote:


James,

I have about 6000 miles on mine.

Fair Winds

Eric

Kimberlite Amel Super Maramu #376





From: amelyachtowners@... <mailto:amelyachtowners@...> [mailto:amelyachtowners@... <mailto:amelyachtowners@...>]
Sent: Tuesday, December 19, 2017 10:54 AM
To: amelyachtowners@... <mailto:amelyachtowners@...>
Subject: Re: [Amel Yacht Owners] Hurth Transmissions freewheeling folding prop





Gabriele Anolini,



That is amazing, you must be taking exceptional care of your transmission. Do you have a cooler on your transmission? Foley seems to be saying that 1000 hours is about all that we should expect. It would be nice to know which factors seem to lead to a longer service life.



Happy Holidays,



James



SV Sueno

Maramu #220



On Dec 19, 2017, at 11:25 AM, Gabriele Antolini svsunnyside@... <mailto:svsunnyside@...> [amelyachtowners] <amelyachtowners@... <mailto:amelyachtowners@...>> wrote:





James



I can confirm you that the Hurth 250 transmission can work much more than 4,000 hours.. Mine passed 10,000 hours and , still now, never gave me a problem.



Best



Gabriele Antolini

SV Sunny Side

Maramu #219

Todomar Yard Cartagena



From: "James Alton lokiyawl2@... <mailto:lokiyawl2@...> [amelyachtowners]" <amelyachtowners@... <mailto:amelyachtowners@...>>
To: amelyachtowners@... <mailto:amelyachtowners@...>
Sent: Monday, 18 December 2017, 23:42
Subject: Re: [Amel Yacht Owners] Hurth Transmissions freewheeling folding prop





Dave,



Thanks for this information. At least I now know that at least some of the Hurth 250 transmissions installed on Maramu’s are lasting longer than the 4,000 hours that mine has. So far my transmission seems to be working fine but the failure mode that you experienced does not sound like a pleasant to experience so maybe I will do something preemptive before long..



I have heard of others having a problem with their aluminum coolers corroding quickly as well.. Without being bonded, I would think that the aluminum parts immersed in seawater would become the sacrificial items on the engine so maybe that could be part of your problem as you suspect. I am wondering however if there is more than one manufacturer of these coolers with some being made of a more corrosion resistant alloy? The original cooler on my transmission had a plate on it that in large letters had the name Hurth, Monchen, Made in West Germany. The old rusty hose clamps, hoses and the apparent age of the ID plate and mounting bolts suggests to me that this cooler had been on the transmission for a very long time. The one that I ordered as a replacement and installed this year with all new hoses was sold by “Mr Cool” 3306107001 ZF Transmission/Gear Cooler. The replacement cooler cost $165.00 USD. The Cooler being sold by Foley is much more expensive, $395.00 which comes with a quart of their special synthetic fluid. I think I will inquire and see what they say about the large cost differential. Can you tell me where you have been buying your coolers?



In part over corrosion concerns for my cooler, I have been flushing the engine with fresh water whenever the engine will sit for more than a couple of days which I think should help to reduce the corrosion some. I think that I will open the cooler at least every couple of seasons to see how much corrosion is present.



Best,



James Alton

SV Sueno, #220

Arbatax, Italy



On Dec 18, 2017, at 8:32 PM, David Wallace svairops@hotmail..com <mailto:svairops@...> [amelyachtowners] <amelyachtowners@... <mailto:amelyachtowners@...>> wrote:



James,



Our Hurth 250 started acting up in 2002 with about 6000 hours on the engine. Intermittently it would not go into forward, first discovered when backing out of a slip which made for an interesting evolution. We had it rebuilt with no issue.



Maybe I have a grounding problem on the 4.154 but the aluminum cooler only seems to last a year or two. I now have several, and try to catch the corrosion before it gets to bad. Then I clean up the cooler and rebuild it with aluminum epoxy that I buy from Cotronics. Works really well.



Regards,



Dave

s/v Air Ops

Maramu #104



On Dec 18, 2017, at 7:50 AM, James Alton lokiyawl2@... <mailto:lokiyawl2@aol..com> [amelyachtowners] <amelyachtowners@... <mailto:amelyachtowners@...>> wrote:




Mike,



My Maramu has a plate mounted just in front of the shift lever warning to never leave the transmission in Fwd. gear while sailing. My boat has a fixed 20” (?) 3 blade prop which can produce a large amount of torque when sailing at higher speeds. I am guessing that since your prop feathers(so produces little torque if any when feathered) that it may not matter as much which gear you use but apparently due to the design the Reverse gear is stronger and therefore safer to use when locking the prop shaft. Perhaps others can verify if this would be correct.



I also read in Foley the these gears seem to last about 1000 hours on average. The gear on my boat has the same paint as the engine and I don’t see any evidence of it having been replaced. The engine now has just over 4,000 hours. Could others comment on the life expectancy the have experienced with the Hurth gears? My boat appears to have had an aluminum cooler for a very long time, it may in fact have been original based on the installation. I replaced the old cooler with a new aluminum one. The old one was not leaking but when cleaning out the inside I found several pin holes that were only plugged with corrosion so it was overdue. I just got an email back from Foley saying that they have discontinued selling the stainless coolers and now only sell the aluminum. I wonder if there were corrosion concerns betwee the aluminum gear case and the stainless coolers. I will try to find out.



Best,



James

SV Sueno, Maramu #220



On Dec 18, 2017, at 11:19 AM, 'Mike Ondra' mdondra@... <mailto:mdondra@...> [amelyachtowners] <amelyachtowners@... <mailto:amelyachtowners@...>> wrote:





Who’d of thought there was so much to know about transmissions and their lubrication! Foley website full of interesting information. On a related topic..



Dr. Diesel Tip #101 at Foley says DO NOT put Hurth trans into forward to stop freewheeling, only reverse.

We have always put the trans in forward to stop the freewheeling and fold the Autoprop when under sail. Given Amels have a “C” drive, does Dr. Diesels Tip apply? Have to pose the question just in case there are opinions among our ranks.



Mike Ondra

Aletes SM#240

Falmouth Harbor, Antigua




















James Alton
 

Gabriele,

   I am glad that you are having good luck!  Thanks for the tip on the Militec-1, what I have read about the product sounds very promising.  I will order some and give it a try.

   So if I understand you correctly,  you changed your aluminum cooler back in 1997 when the engine had 4,000 hours on it,  you now have 10,000 hours on your engine and you are still using the same cooler?  May I ask where you ordered your cooler from?  It seems that some people are having problems with their coolers corroding quickly.

   Perhaps our boats were built side by side side since Sueno is #220?   May I ask where your boat is now?

Best,

James 
SV Sueno
Maramu #220

On Dec 19, 2017, at 4:00 PM, Gabriele Antolini svsunnyside@... [amelyachtowners] <amelyachtowners@...> wrote:


Hi James
 - Good care : YES  ,  Exceptional care: I do not think so. The only thing I use ,  that not everyone use ,  is:  MILITEC-1 (everywhere possible, on sea and on land) according to the producer recommendations . Nothing to do with the cooler.
 - Cooler  : Yes I have the small square aluminum cooler. I changed it on 97 . when I received the boat, with 4,000 hours.
From 99 to 2006 I was living on board using marinas only when could not be evitable. In the last ten years, at the end of my four months sailing season, in April, I ran the engine for one hour with fresh water(half an hour one day and half an hour, one day or two later) . 
A little of luck is always welcome. 

Gabriele
SV Sunny Side
Maramu #219

From: "James Alton lokiyawl2@... [amelyachtowners]" <amelyachtowners@...>
To: amelyachtowners@... 
Sent: Tuesday, 19 December 2017, 12:06
Subject: Re: [Amel Yacht Owners] Hurth Transmissions freewheeling folding prop

 
Gabriele Anolini,

   That is amazing,  you must be taking exceptional care of your transmission.  Do you have a cooler on your transmission?  Foley seems to be saying that 1000 hours is about all that we should expect.  It would be nice to know which factors seem to lead to a longer service life.   

Happy Holidays,

James

SV Sueno
Maramu #220

On Dec 19, 2017, at 11:25 AM, Gabriele Antolini svsunnyside@... [amelyachtowners] <amelyachtowners@...> wrote:


James

I can confirm you that the Hurth 250 transmission can work much more than 4,000 hours. Mine passed 10,000 hours and , still now, never gave me a problem.

Best

Gabriele Antolini
SV Sunny Side 
Maramu #219
Todomar Yard Cartagena



From: "James Alton lokiyawl2@... [amelyachtowners]" <amelyachtowners@...>
To: amelyachtowners@... 
Sent: Monday, 18 December 2017, 23:42
Subject: Re: [Amel Yacht Owners] Hurth Transmissions freewheeling folding prop

 
Dave,

   Thanks for this information.  At least I now know that at least some of the Hurth 250 transmissions installed on Maramu’s are lasting longer than the 4,000 hours that mine has.  So far my transmission seems to be working fine but the failure mode that you experienced does not sound like a pleasant to experience so maybe I will do something preemptive before long.  

    I have heard of others having a problem with their aluminum coolers corroding quickly as well..  Without being bonded, I would think that the aluminum parts immersed in seawater would become the sacrificial items on the engine so maybe that could be part of your problem as you suspect.  I am wondering however if there is more than one manufacturer of these coolers with some being made of a more corrosion resistant alloy?  The original cooler on my transmission had a plate on it that in large letters had the name Hurth,  Monchen,  Made in West Germany.  The old rusty hose clamps, hoses and the apparent age of the ID plate and mounting bolts suggests to me that this cooler had been on the transmission for a very long time.  The one that I ordered as a replacement and installed this year with all new hoses was sold by “Mr Cool” 3306107001 ZF Transmission/Gear Cooler.  The replacement cooler cost $165.00 USD.  The Cooler being sold by Foley is much more expensive,  $395.00 which comes with a quart of their special synthetic fluid. I think I will inquire and see what they say about the large cost differential.    Can you tell me where you have been buying your coolers?

    In part over corrosion concerns for my cooler, I have been flushing the engine with fresh water whenever the engine will sit for more than a couple of days which I think should help to reduce the corrosion some.   I think that I will open the cooler at least every couple of seasons to see how much corrosion is present.  

Best,

James  Alton
SV Sueno,  #220
Arbatax,  Italy

On Dec 18, 2017, at 8:32 PM, David Wallace svairops@hotmail..com [amelyachtowners] <amelyachtowners@...> wrote:

James, 

Our Hurth 250 started acting up in 2002 with about 6000 hours on the engine. Intermittently it would not go into forward, first discovered when backing out of a slip which made for an interesting evolution. We had it rebuilt with no issue.

Maybe I have a grounding problem on the 4.154 but the aluminum cooler only seems to last a year or two. I now have several, and try to catch the corrosion before it gets to bad. Then I clean up the cooler and rebuild it with aluminum epoxy that I buy from Cotronics. Works really well.

Regards,

Dave
s/v Air Ops
Maramu #104

On Dec 18, 2017, at 7:50 AM, James Alton lokiyawl2@... [amelyachtowners] <amelyachtowners@...> wrote:

Mike,

   My Maramu has a plate mounted just in front of the shift lever warning to never leave the transmission in Fwd. gear while sailing.  My boat has a fixed 20” (?) 3 blade prop which can produce a large amount of torque when sailing at higher speeds.  I am guessing that since your prop feathers(so produces little torque if any when feathered)  that it may not matter as much which gear you use but apparently due to the design the Reverse gear is stronger and therefore safer to use when locking the prop shaft.  Perhaps others can verify if this would be correct.

   I also read in Foley the these gears seem to last about 1000 hours on average.  The gear on my boat has the same paint as the engine and I don’t see any evidence of it having been replaced.  The engine now has just over 4,000 hours.  Could others comment on the life expectancy the have experienced with the Hurth gears?  My boat appears to have had an aluminum cooler for a very long time,  it may in fact have been original based on the installation.  I replaced the old cooler with a new aluminum one.  The old one was not leaking but when cleaning out the inside I found several pin holes that were only plugged with corrosion so it was overdue.  I just got an email back from Foley saying that they have discontinued selling the stainless coolers and now only sell the aluminum.  I wonder if there were corrosion concerns betwee the aluminum gear case and the stainless coolers.  I will try to find out. 

Best,

James
SV Sueno,  Maramu #220

On Dec 18, 2017, at 11:19 AM, 'Mike Ondra' mdondra@... [amelyachtowners] <amelyachtowners@...> wrote:


Who’d of thought there was so much to know about transmissions and their lubrication! Foley website full of interesting information. On a related topic..
 
Dr.. Diesel Tip #101 at Foley says DO NOT put Hurth trans into forward to stop freewheeling, only reverse.
We have always put the trans in forward to stop the freewheeling and fold the Autoprop when under sail. Given Amels have a “C” drive, does Dr. Diesels Tip apply? Have to pose the question just in case there are opinions among our ranks.
 
Mike Ondra
Aletes SM#240
Falmouth Harbor, Antigua
 














eric freedman
 

Sorry,

6000 hours

Fair Winds

Eric

 

 

From: amelyachtowners@... [mailto:amelyachtowners@...]
Sent: Tuesday, December 19, 2017 6:22 PM
To: amelyachtowners@...
Subject: Re: [Amel Yacht Owners] Hurth Transmissions freewheeling folding prop

 

 

Hi Eric,

 

   Did you mean to type 6000 hours or miles?

 

Best,

 

James

SV Sueno,  Maramu #220

 

On Dec 19, 2017, at 5:27 PM, 'sailormon' kimberlite@... [amelyachtowners] <amelyachtowners@...> wrote:

 

 

James,

I have about 6000 miles on mine.

Fair Winds

Eric

Kimberlite Amel Super Maramu #376

 

 

From: amelyachtowners@... [mailto:amelyachtowners@...] 
Sent: Tuesday, December 19, 2017 10:54 AM
To: amelyachtowners@...
Subject: Re: [Amel Yacht Owners] Hurth Transmissions freewheeling folding prop

 

  

Gabriele Anolini,

 

   That is amazing,  you must be taking exceptional care of your transmission.  Do you have a cooler on your transmission?  Foley seems to be saying that 1000 hours is about all that we should expect.  It would be nice to know which factors seem to lead to a longer service life.   

 

Happy Holidays,

 

James

 

SV Sueno

Maramu #220

 

On Dec 19, 2017, at 11:25 AM, Gabriele Antolini svsunnyside@... [amelyachtowners] <amelyachtowners@...> wrote:

 

 

James

 

I can confirm you that the Hurth 250 transmission can work much more than 4,000 hours.. Mine passed 10,000 hours and , still now, never gave me a problem.

 

Best

 

Gabriele Antolini

SV Sunny Side 

Maramu #219

Todomar Yard Cartagena

 


From: "James Alton lokiyawl2@... [amelyachtowners]" <amelyachtowners@...>
To: amelyachtowners@... 
Sent: Monday, 18 December 2017, 23:42
Subject: Re: [Amel Yacht Owners] Hurth Transmissions freewheeling folding prop

 

 

Dave,

 

   Thanks for this information.  At least I now know that at least some of the Hurth 250 transmissions installed on Maramu’s are lasting longer than the 4,000 hours that mine has.  So far my transmission seems to be working fine but the failure mode that you experienced does not sound like a pleasant to experience so maybe I will do something preemptive before long..  

 

    I have heard of others having a problem with their aluminum coolers corroding quickly as well..  Without being bonded, I would think that the aluminum parts immersed in seawater would become the sacrificial items on the engine so maybe that could be part of your problem as you suspect.  I am wondering however if there is more than one manufacturer of these coolers with some being made of a more corrosion resistant alloy?  The original cooler on my transmission had a plate on it that in large letters had the name Hurth,  Monchen,  Made in West Germany.  The old rusty hose clamps, hoses and the apparent age of the ID plate and mounting bolts suggests to me that this cooler had been on the transmission for a very long time.  The one that I ordered as a replacement and installed this year with all new hoses was sold by “Mr Cool” 3306107001 ZF Transmission/Gear Cooler.  The replacement cooler cost $165.00 USD.  The Cooler being sold by Foley is much more expensive,  $395.00 which comes with a quart of their special synthetic fluid. I think I will inquire and see what they say about the large cost differential.    Can you tell me where you have been buying your coolers?

 

    In part over corrosion concerns for my cooler, I have been flushing the engine with fresh water whenever the engine will sit for more than a couple of days which I think should help to reduce the corrosion some.   I think that I will open the cooler at least every couple of seasons to see how much corrosion is present.  

 

Best,

 

James  Alton

SV Sueno,  #220

Arbatax,  Italy

 

On Dec 18, 2017, at 8:32 PM, David Wallace svairops@hotmail..com [amelyachtowners] <amelyachtowners@...> wrote:

 

James, 

 

Our Hurth 250 started acting up in 2002 with about 6000 hours on the engine. Intermittently it would not go into forward, first discovered when backing out of a slip which made for an interesting evolution. We had it rebuilt with no issue.

 

Maybe I have a grounding problem on the 4.154 but the aluminum cooler only seems to last a year or two. I now have several, and try to catch the corrosion before it gets to bad. Then I clean up the cooler and rebuild it with aluminum epoxy that I buy from Cotronics. Works really well.

 

Regards,

 

Dave

s/v Air Ops

Maramu #104

 

On Dec 18, 2017, at 7:50 AM, James Alton lokiyawl2@... [amelyachtowners] <amelyachtowners@...> wrote:




Mike,

 

   My Maramu has a plate mounted just in front of the shift lever warning to never leave the transmission in Fwd. gear while sailing.  My boat has a fixed 20” (?) 3 blade prop which can produce a large amount of torque when sailing at higher speeds.  I am guessing that since your prop feathers(so produces little torque if any when feathered)  that it may not matter as much which gear you use but apparently due to the design the Reverse gear is stronger and therefore safer to use when locking the prop shaft.  Perhaps others can verify if this would be correct..

 

   I also read in Foley the these gears seem to last about 1000 hours on average.  The gear on my boat has the same paint as the engine and I don’t see any evidence of it having been replaced.  The engine now has just over 4,000 hours.  Could others comment on the life expectancy the have experienced with the Hurth gears?  My boat appears to have had an aluminum cooler for a very long time,  it may in fact have been original based on the installation.  I replaced the old cooler with a new aluminum one.  The old one was not leaking but when cleaning out the inside I found several pin holes that were only plugged with corrosion so it was overdue.  I just got an email back from Foley saying that they have discontinued selling the stainless coolers and now only sell the aluminum.  I wonder if there were corrosion concerns betwee the aluminum gear case and the stainless coolers.  I will try to find out. 

 

Best,

 

James

SV Sueno,  Maramu #220

 

On Dec 18, 2017, at 11:19 AM, 'Mike Ondra' mdondra@... [amelyachtowners] <amelyachtowners@...> wrote:

 

 

Who’d of thought there was so much to know about transmissions and their lubrication! Foley website full of interesting information. On a related topic..

 

Dr. Diesel Tip #101 at Foley says DO NOT put Hurth trans into forward to stop freewheeling, only reverse.

We have always put the trans in forward to stop the freewheeling and fold the Autoprop when under sail. Given Amels have a “C” drive, does Dr. Diesels Tip apply? Have to pose the question just in case there are opinions among our ranks.

 

Mike Ondra

Aletes SM#240

Falmouth Harbor, Antigua

 

 

 

 

 

 

 

 

 

 

 

 

James Alton
 

Dave,

   I discovered while searching online that Foley used to source their coolers from Germany but stopped doing so because they were corroding too quickly.   I am guessing that these might be the same unit that was on Sueno and from your email, yours as well.  Steno’s cooler may have survived for much longer than it should because she was on the hard for many years and only used seasonally.  Foley also said that because of the short service life of the German aluminum coolers  they started making the stainless coolers that have now been discontinued. So I am wondering where there coolers are coming from now?   You can read about the problem they had with the aluminum coolers under item #2 at: https://www.foleyengines.com/tech-tip-96-zfhurth-marine-transmissions-six-step-program/    I am trying to find out more about the coolers that they sell and have another email into to them.   It would be so sad to lose a boat because of a corroded cooler.  

Best,

James
SV Sueno
Maramu #220


On Dec 19, 2017, at 3:01 PM, David Wallace svairops@... [amelyachtowners] <amelyachtowners@...> wrote:

James,


I have one of those plates as well. Interestingly, the plates, old and new, never seem to corrode much, just the box itself. The most worrisome corrosion is to the pipes that the hoses are clamped on — obviously there would be a major problem if one of those failed. So the box and hose connections are part of my engine room check list I go through every time prior to starting the engine. And I also flush the engine with fresh water when we lay up the boat for more than a couple of weeks.

My source for the cooler box has been Trans Atlantic Diesel (www.tadiesels.com), located in Virginia. Like Foley, they specialize in Perkins and have been very helpful in providing parts for the old 4.154. I think their price for the cooler box is about what you paid.

Best regards,

Dave
s/v Air Ops
Maramu #104
Puerto Escondido, BCS, Mx

On Dec 18, 2017, at 7:42 PM, James Alton lokiyawl2@... [amelyachtowners] <amelyachtowners@...> wrote:

Dave,


   Thanks for this information.  At least I now know that at least some of the Hurth 250 transmissions installed on Maramu’s are lasting longer than the 4,000 hours that mine has.  So far my transmission seems to be working fine but the failure mode that you experienced does not sound like a pleasant to experience so maybe I will do something preemptive before long.  

    I have heard of others having a problem with their aluminum coolers corroding quickly as well..  Without being bonded, I would think that the aluminum parts immersed in seawater would become the sacrificial items on the engine so maybe that could be part of your problem as you suspect.  I am wondering however if there is more than one manufacturer of these coolers with some being made of a more corrosion resistant alloy?  The original cooler on my transmission had a plate on it that in large letters had the name Hurth,  Monchen,  Made in West Germany.  The old rusty hose clamps, hoses and the apparent age of the ID plate and mounting bolts suggests to me that this cooler had been on the transmission for a very long time.  The one that I ordered as a replacement and installed this year with all new hoses was sold by “Mr Cool” 3306107001 ZF Transmission/Gear Cooler.  The replacement cooler cost $165.00 USD.  The Cooler being sold by Foley is much more expensive,  $395.00 which comes with a quart of their special synthetic fluid. I think I will inquire and see what they say about the large cost differential.    Can you tell me where you have been buying your coolers?

    In part over corrosion concerns for my cooler, I have been flushing the engine with fresh water whenever the engine will sit for more than a couple of days which I think should help to reduce the corrosion some.   I think that I will open the cooler at least every couple of seasons to see how much corrosion is present.  

Best,

James  Alton
SV Sueno,  #220
Arbatax,  Italy

On Dec 18, 2017, at 8:32 PM, David Wallace svairops@... [amelyachtowners] <amelyachtowners@...> wrote:

James, 


Our Hurth 250 started acting up in 2002 with about 6000 hours on the engine. Intermittently it would not go into forward, first discovered when backing out of a slip which made for an interesting evolution. We had it rebuilt with no issue.

Maybe I have a grounding problem on the 4.154 but the aluminum cooler only seems to last a year or two. I now have several, and try to catch the corrosion before it gets to bad. Then I clean up the cooler and rebuild it with aluminum epoxy that I buy from Cotronics. Works really well.

Regards,

Dave
s/v Air Ops
Maramu #104

On Dec 18, 2017, at 7:50 AM, James Alton lokiyawl2@... [amelyachtowners] <amelyachtowners@...> wrote:

Mike,


   My Maramu has a plate mounted just in front of the shift lever warning to never leave the transmission in Fwd. gear while sailing.  My boat has a fixed 20” (?) 3 blade prop which can produce a large amount of torque when sailing at higher speeds.  I am guessing that since your prop feathers(so produces little torque if any when feathered)  that it may not matter as much which gear you use but apparently due to the design the Reverse gear is stronger and therefore safer to use when locking the prop shaft.  Perhaps others can verify if this would be correct.

   I also read in Foley the these gears seem to last about 1000 hours on average.  The gear on my boat has the same paint as the engine and I don’t see any evidence of it having been replaced.  The engine now has just over 4,000 hours.  Could others comment on the life expectancy the have experienced with the Hurth gears?  My boat appears to have had an aluminum cooler for a very long time,  it may in fact have been original based on the installation.  I replaced the old cooler with a new aluminum one.  The old one was not leaking but when cleaning out the inside I found several pin holes that were only plugged with corrosion so it was overdue.  I just got an email back from Foley saying that they have discontinued selling the stainless coolers and now only sell the aluminum.  I wonder if there were corrosion concerns betwee the aluminum gear case and the stainless coolers.  I will try to find out. 

Best,

James
SV Sueno,  Maramu #220

On Dec 18, 2017, at 11:19 AM, 'Mike Ondra' mdondra@... [amelyachtowners] <amelyachtowners@...> wrote:


Who’d of thought there was so much to know about transmissions and their lubrication! Foley website full of interesting information. On a related topic..

 

Dr. Diesel Tip #101 at Foley says DO NOT put Hurth trans into forward to stop freewheeling, only reverse.

We have always put the trans in forward to stop the freewheeling and fold the Autoprop when under sail. Given Amels have a “C” drive, does Dr. Diesels Tip apply? Have to pose the question just in case there are opinions among our ranks.

 

Mike Ondra

Aletes SM#240

Falmouth Harbor, Antigua

 











greatketch@...
 

1000 hours for the life of a Hurth transmission?   No way.  

Something is very wrong with that number.  Properly cared for they should last as long as the engine... maybe 10,000 hours?

Bill Kinney
SM160, Harmonie
Big Pine Key, Florida


hanspeter baettig
 

Hello James
I'm amusing my self and others Amel Owners here in Europe. Dont't worry you will never lose your Amel Boat about a corrodes Hurth  Cooler.!
You cetainly know who is the builder of Hurth? Best Ygermsm qualitiy, not US. The company is ZF Friedrichshafen, Bodensee;Googel it
they buit the first and only Zeppelins.

Von meinem iPhone gesendet

Am 19.12.2017 um 23:58 schrieb James Alton lokiyawl2@... [amelyachtowners] <amelyachtowners@...>:

 

Dave,


   I discovered while searching online that Foley used to source their coolers from Germany but stopped doing so because they were corroding too quickly.   I am guessing that these might be the same unit that was on Sueno and from your email, yours as well.  Steno’s cooler may have survived for much longer than it should because she was on the hard for many years and only used seasonally.  Foley also said that because of the short service life of the German aluminum coolers  they started making the stainless coolers that have now been discontinued. So I am wondering where there coolers are coming from now?   You can read about the problem they had with the aluminum coolers under item #2 at: https://www.foleyengines.com/tech-tip-96-zfhurth-marine-transmissions-six-step-program/    I am trying to find out more about the coolers that they sell and have another email into to them.   It would be so sad to lose a boat because of a corroded cooler.  

Best,

James
SV Sueno
Maramu #220


On Dec 19, 2017, at 3:01 PM, David Wallace svairops@... [amelyachtowners] <amelyachtowners@...> wrote:

James,


I have one of those plates as well. Interestingly, the plates, old and new, never seem to corrode much, just the box itself. The most worrisome corrosion is to the pipes that the hoses are clamped on — obviously there would be a major problem if one of those failed. So the box and hose connections are part of my engine room check list I go through every time prior to starting the engine. And I also flush the engine with fresh water when we lay up the boat for more than a couple of weeks.

My source for the cooler box has been Trans Atlantic Diesel (www.tadiesels.com), located in Virginia. Like Foley, they specialize in Perkins and have been very helpful in providing parts for the old 4.154. I think their price for the cooler box is about what you paid.

Best regards,

Dave
s/v Air Ops
Maramu #104
Puerto Escondido, BCS, Mx

On Dec 18, 2017, at 7:42 PM, James Alton lokiyawl2@... [amelyachtowners] <amelyachtowners@...> wrote:

Dave,


   Thanks for this information.  At least I now know that at least some of the Hurth 250 transmissions installed on Maramu’s are lasting longer than the 4,000 hours that mine has.  So far my transmission seems to be working fine but the failure mode that you experienced does not sound like a pleasant to experience so maybe I will do something preemptive before long.  

    I have heard of others having a problem with their aluminum coolers corroding quickly as well..  Without being bonded, I would think that the aluminum parts immersed in seawater would become the sacrificial items on the engine so maybe that could be part of your problem as you suspect.  I am wondering however if there is more than one manufacturer of these coolers with some being made of a more corrosion resistant alloy?  The original cooler on my transmission had a plate on it that in large letters had the name Hurth,  Monchen,  Made in West Germany.  The old rusty hose clamps, hoses and the apparent age of the ID plate and mounting bolts suggests to me that this cooler had been on the transmission for a very long time.  The one that I ordered as a replacement and installed this year with all new hoses was sold by “Mr Cool” 3306107001 ZF Transmission/Gear Cooler.  The replacement cooler cost $165.00 USD.  The Cooler being sold by Foley is much more expensive,  $395.00 which comes with a quart of their special synthetic fluid. I think I will inquire and see what they say about the large cost differential.    Can you tell me where you have been buying your coolers?

    In part over corrosion concerns for my cooler, I have been flushing the engine with fresh water whenever the engine will sit for more than a couple of days which I think should help to reduce the corrosion some.   I think that I will open the cooler at least every couple of seasons to see how much corrosion is present.  

Best,

James  Alton
SV Sueno,  #220
Arbatax,  Italy

On Dec 18, 2017, at 8:32 PM, David Wallace svairops@hotmail..com [amelyachtowners] <amelyachtowners@...> wrote:

James, 


Our Hurth 250 started acting up in 2002 with about 6000 hours on the engine. Intermittently it would not go into forward, first discovered when backing out of a slip which made for an interesting evolution. We had it rebuilt with no issue.

Maybe I have a grounding problem on the 4.154 but the aluminum cooler only seems to last a year or two. I now have several, and try to catch the corrosion before it gets to bad. Then I clean up the cooler and rebuild it with aluminum epoxy that I buy from Cotronics. Works really well.

Regards,

Dave
s/v Air Ops
Maramu #104

On Dec 18, 2017, at 7:50 AM, James Alton lokiyawl2@... [amelyachtowners] <amelyachtowners@...> wrote:

Mike,


   My Maramu has a plate mounted just in front of the shift lever warning to never leave the transmission in Fwd. gear while sailing.  My boat has a fixed 20” (?) 3 blade prop which can produce a large amount of torque when sailing at higher speeds.  I am guessing that since your prop feathers(so produces little torque if any when feathered)  that it may not matter as much which gear you use but apparently due to the design the Reverse gear is stronger and therefore safer to use when locking the prop shaft.  Perhaps others can verify if this would be correct.

   I also read in Foley the these gears seem to last about 1000 hours on average.  The gear on my boat has the same paint as the engine and I don’t see any evidence of it having been replaced.  The engine now has just over 4,000 hours.  Could others comment on the life expectancy the have experienced with the Hurth gears?  My boat appears to have had an aluminum cooler for a very long time,  it may in fact have been original based on the installation.  I replaced the old cooler with a new aluminum one.  The old one was not leaking but when cleaning out the inside I found several pin holes that were only plugged with corrosion so it was overdue.  I just got an email back from Foley saying that they have discontinued selling the stainless coolers and now only sell the aluminum.  I wonder if there were corrosion concerns betwee the aluminum gear case and the stainless coolers.  I will try to find out. 

Best,

James
SV Sueno,  Maramu #220

On Dec 18, 2017, at 11:19 AM, 'Mike Ondra' mdondra@... [amelyachtowners] <amelyachtowners@...> wrote:


Who’d of thought there was so much to know about transmissions and their lubrication! Foley website full of interesting information. On a related topic..

 

Dr. Diesel Tip #101 at Foley says DO NOT put Hurth trans into forward to stop freewheeling, only reverse.

We have always put the trans in forward to stop the freewheeling and fold the Autoprop when under sail. Given Amels have a “C” drive, does Dr. Diesels Tip apply? Have to pose the question just in case there are opinions among our ranks.

 

Mike Ondra

Aletes SM#240

Falmouth Harbor, Antigua

 











James Alton
 

Bill,

  The Foley website refers to this number on the basis of some customers that were replacing or rebuilding their transmissions at about 1000 hours. https://www.foleyengines.com/tech-tip-106-zfhurth-gears-dollar-hour-gear/   

 Foley provided a list of reasons that some people were getting such poor service life such as:

1.  Mating a marginal or undersized transmission to too large of an engine.
2.  Allowing these gears to get low on fluid.  The point being that these gears hold so little that even a small loss is critical)
3.  Saltwater corrosion eating through the case.
4.  Prop wraps.

Basically reasons that with some reasonable care, maintenance and a proper initial installation that can be avoided.  I am getting the impression that good maintenance and coolers are pretty important to the life of these boxes.    It appears that on my boat that Amel oversized the transmission a quite a  bit and I have heard from a number of other Maramu owners that have as many as 10,000 hours on their transmissions.  


Best,

James
SV Sueno
Maramu #220


On Dec 19, 2017, at 8:02 PM, greatketch@... [amelyachtowners] <amelyachtowners@...> wrote:

1000 hours for the life of a Hurth transmission?   No way.  


Something is very wrong with that number.  Properly cared for they should last as long as the engine... maybe 10,000 hours?

Bill Kinney
SM160, Harmonie
Big Pine Key, Florida




hanspeter baettig
 

Sorry I sent it to early,
correction: Germany
Regards
Hanspeter
Tamango 2; SM 16
Lancarote

Von meinem iPhone gesendet

Am 20.12.2017 um 00:28 schrieb "hanspeter.baettig@..." <hanspeter.baettig@...>:

Hello James
I'm amusing my self and others Amel Owners here in Europe. Dont't worry you will never lose your Amel Boat about a corrodes Hurth  Cooler.!
You cetainly know who is the builder of Hurth? Best Ygermsm qualitiy, not US. The company is ZF Friedrichshafen, Bodensee;Googel it
they buit the first and only Zeppelins.

Von meinem iPhone gesendet

Am 19.12.2017 um 23:58 schrieb James Alton lokiyawl2@... [amelyachtowners] <amelyachtowners@...>:

 

Dave,


   I discovered while searching online that Foley used to source their coolers from Germany but stopped doing so because they were corroding too quickly.   I am guessing that these might be the same unit that was on Sueno and from your email, yours as well.  Steno’s cooler may have survived for much longer than it should because she was on the hard for many years and only used seasonally.  Foley also said that because of the short service life of the German aluminum coolers  they started making the stainless coolers that have now been discontinued. So I am wondering where there coolers are coming from now?   You can read about the problem they had with the aluminum coolers under item #2 at: https://www.foleyengines.com/tech-tip-96-zfhurth-marine-transmissions-six-step-program/    I am trying to find out more about the coolers that they sell and have another email into to them.   It would be so sad to lose a boat because of a corroded cooler.  

Best,

James
SV Sueno
Maramu #220


On Dec 19, 2017, at 3:01 PM, David Wallace svairops@... [amelyachtowners] <amelyachtowners@...> wrote:

James,


I have one of those plates as well. Interestingly, the plates, old and new, never seem to corrode much, just the box itself. The most worrisome corrosion is to the pipes that the hoses are clamped on — obviously there would be a major problem if one of those failed. So the box and hose connections are part of my engine room check list I go through every time prior to starting the engine. And I also flush the engine with fresh water when we lay up the boat for more than a couple of weeks.

My source for the cooler box has been Trans Atlantic Diesel (www.tadiesels.com), located in Virginia. Like Foley, they specialize in Perkins and have been very helpful in providing parts for the old 4.154. I think their price for the cooler box is about what you paid.

Best regards,

Dave
s/v Air Ops
Maramu #104
Puerto Escondido, BCS, Mx

On Dec 18, 2017, at 7:42 PM, James Alton lokiyawl2@... [amelyachtowners] <amelyachtowners@...> wrote:

Dave,


   Thanks for this information.  At least I now know that at least some of the Hurth 250 transmissions installed on Maramu’s are lasting longer than the 4,000 hours that mine has.  So far my transmission seems to be working fine but the failure mode that you experienced does not sound like a pleasant to experience so maybe I will do something preemptive before long.  

    I have heard of others having a problem with their aluminum coolers corroding quickly as well..  Without being bonded, I would think that the aluminum parts immersed in seawater would become the sacrificial items on the engine so maybe that could be part of your problem as you suspect.  I am wondering however if there is more than one manufacturer of these coolers with some being made of a more corrosion resistant alloy?  The original cooler on my transmission had a plate on it that in large letters had the name Hurth,  Monchen,  Made in West Germany.  The old rusty hose clamps, hoses and the apparent age of the ID plate and mounting bolts suggests to me that this cooler had been on the transmission for a very long time.  The one that I ordered as a replacement and installed this year with all new hoses was sold by “Mr Cool” 3306107001 ZF Transmission/Gear Cooler.  The replacement cooler cost $165.00 USD.  The Cooler being sold by Foley is much more expensive,  $395.00 which comes with a quart of their special synthetic fluid. I think I will inquire and see what they say about the large cost differential.    Can you tell me where you have been buying your coolers?

    In part over corrosion concerns for my cooler, I have been flushing the engine with fresh water whenever the engine will sit for more than a couple of days which I think should help to reduce the corrosion some.   I think that I will open the cooler at least every couple of seasons to see how much corrosion is present.  

Best,

James  Alton
SV Sueno,  #220
Arbatax,  Italy

On Dec 18, 2017, at 8:32 PM, David Wallace svairops@hotmail..com [amelyachtowners] <amelyachtowners@...> wrote:

James, 


Our Hurth 250 started acting up in 2002 with about 6000 hours on the engine. Intermittently it would not go into forward, first discovered when backing out of a slip which made for an interesting evolution. We had it rebuilt with no issue.

Maybe I have a grounding problem on the 4.154 but the aluminum cooler only seems to last a year or two. I now have several, and try to catch the corrosion before it gets to bad. Then I clean up the cooler and rebuild it with aluminum epoxy that I buy from Cotronics. Works really well.

Regards,

Dave
s/v Air Ops
Maramu #104

On Dec 18, 2017, at 7:50 AM, James Alton lokiyawl2@... [amelyachtowners] <amelyachtowners@...> wrote:

Mike,


   My Maramu has a plate mounted just in front of the shift lever warning to never leave the transmission in Fwd. gear while sailing.  My boat has a fixed 20” (?) 3 blade prop which can produce a large amount of torque when sailing at higher speeds.  I am guessing that since your prop feathers(so produces little torque if any when feathered)  that it may not matter as much which gear you use but apparently due to the design the Reverse gear is stronger and therefore safer to use when locking the prop shaft.  Perhaps others can verify if this would be correct.

   I also read in Foley the these gears seem to last about 1000 hours on average.  The gear on my boat has the same paint as the engine and I don’t see any evidence of it having been replaced.  The engine now has just over 4,000 hours.  Could others comment on the life expectancy the have experienced with the Hurth gears?  My boat appears to have had an aluminum cooler for a very long time,  it may in fact have been original based on the installation.  I replaced the old cooler with a new aluminum one.  The old one was not leaking but when cleaning out the inside I found several pin holes that were only plugged with corrosion so it was overdue.  I just got an email back from Foley saying that they have discontinued selling the stainless coolers and now only sell the aluminum.  I wonder if there were corrosion concerns betwee the aluminum gear case and the stainless coolers.  I will try to find out. 

Best,

James
SV Sueno,  Maramu #220

On Dec 18, 2017, at 11:19 AM, 'Mike Ondra' mdondra@... [amelyachtowners] <amelyachtowners@...> wrote:


Who’d of thought there was so much to know about transmissions and their lubrication! Foley website full of interesting information. On a related topic..

 

Dr. Diesel Tip #101 at Foley says DO NOT put Hurth trans into forward to stop freewheeling, only reverse.

We have always put the trans in forward to stop the freewheeling and fold the Autoprop when under sail. Given Amels have a “C” drive, does Dr. Diesels Tip apply? Have to pose the question just in case there are opinions among our ranks.

 

Mike Ondra

Aletes SM#240

Falmouth Harbor, Antigua

 











svsunnyside
 

James,
Sunny Side is at Todomar Yard Cartagena
Your understanding of my bad english is 100% correct.
End of January, I will be on board and I will look for where I ordered my cooler from.
The name of your boat is Sueno or Sueño ?
Regards
Gabriele
SV Sunny Side
Maramu #219



From: "James Alton lokiyawl2@... [amelyachtowners]"
To: amelyachtowners@...
Sent: Wednesday, 20 December 2017, 9:29
Subject: Re: [Amel Yacht Owners] Hurth Transmissions freewheeling folding prop

 
Gabriele,

   I am glad that you are having good luck!  Thanks for the tip on the Militec-1, what I have read about the product sounds very promising.  I will order some and give it a try.

   So if I understand you correctly,  you changed your aluminum cooler back in 1997 when the engine had 4,000 hours on it,  you now have 10,000 hours on your engine and you are still using the same cooler?  May I ask where you ordered your cooler from?  It seems that some people are having problems with their coolers corroding quickly.

   Perhaps our boats were built side by side side since Sueno is #220?   May I ask where your boat is now?

Best,

James 
SV Sueno
Maramu #220

On Dec 19, 2017, at 4:00 PM, Gabriele Antolini svsunnyside@... [amelyachtowners] <amelyachtowners@...> wrote:


Hi James
 - Good care : YES  ,  Exceptional care: I do not think so. The only thing I use ,  that not everyone use ,  is:  MILITEC-1 (everywhere possible, on sea and on land) according to the producer recommendations . Nothing to do with the cooler.
 - Cooler  : Yes I have the small square aluminum cooler. I changed it on 97 . when I received the boat, with 4,000 hours.
From 99 to 2006 I was living on board using marinas only when could not be evitable. In the last ten years, at the end of my four months sailing season, in April, I ran the engine for one hour with fresh water(half an hour one day and half an hour, one day or two later) . 
A little of luck is always welcome. 

Gabriele
SV Sunny Side
Maramu #219

From: "James Alton lokiyawl2@... [amelyachtowners]" <amelyachtowners@...>
To: amelyachtowners@... 
Sent: Tuesday, 19 December 2017, 12:06
Subject: Re: [Amel Yacht Owners] Hurth Transmissions freewheeling folding prop

 
Gabriele Anolini,

   That is amazing,  you must be taking exceptional care of your transmission.  Do you have a cooler on your transmission?  Foley seems to be saying that 1000 hours is about all that we should expect.  It would be nice to know which factors seem to lead to a longer service life.   

Happy Holidays,

James

SV Sueno
Maramu #220

On Dec 19, 2017, at 11:25 AM, Gabriele Antolini svsunnyside@... [amelyachtowners] <amelyachtowners@...> wrote:


James

I can confirm you that the Hurth 250 transmission can work much more than 4,000 hours. Mine passed 10,000 hours and , still now, never gave me a problem.

Best

Gabriele Antolini
SV Sunny Side 
Maramu #219
Todomar Yard Cartagena



From: "James Alton lokiyawl2@... [amelyachtowners]" <amelyachtowners@...>
To: amelyachtowners@... 
Sent: Monday, 18 December 2017, 23:42
Subject: Re: [Amel Yacht Owners] Hurth Transmissions freewheeling folding prop

 
Dave,

   Thanks for this information.  At least I now know that at least some of the Hurth 250 transmissions installed on Maramu’s are lasting longer than the 4,000 hours that mine has.  So far my transmission seems to be working fine but the failure mode that you experienced does not sound like a pleasant to experience so maybe I will do something preemptive before long.  

    I have heard of others having a problem with their aluminum coolers corroding quickly as well..  Without being bonded, I would think that the aluminum parts immersed in seawater would become the sacrificial items on the engine so maybe that could be part of your problem as you suspect.  I am wondering however if there is more than one manufacturer of these coolers with some being made of a more corrosion resistant alloy?  The original cooler on my transmission had a plate on it that in large letters had the name Hurth,  Monchen,  Made in West Germany.  The old rusty hose clamps, hoses and the apparent age of the ID plate and mounting bolts suggests to me that this cooler had been on the transmission for a very long time..  The one that I ordered as a replacement and installed this year with all new hoses was sold by “Mr Cool” 3306107001 ZF Transmission/Gear Cooler.  The replacement cooler cost $165.00 USD.  The Cooler being sold by Foley is much more expensive,  $395.00 which comes with a quart of their special synthetic fluid. I think I will inquire and see what they say about the large cost differential.    Can you tell me where you have been buying your coolers?

    In part over corrosion concerns for my cooler, I have been flushing the engine with fresh water whenever the engine will sit for more than a couple of days which I think should help to reduce the corrosion some.   I think that I will open the cooler at least every couple of seasons to see how much corrosion is present.  

Best,

James  Alton
SV Sueno,  #220
Arbatax,  Italy

On Dec 18, 2017, at 8:32 PM, David Wallace svairops@hotmail..com [amelyachtowners] <amelyachtowners@...> wrote:

James, 

Our Hurth 250 started acting up in 2002 with about 6000 hours on the engine. Intermittently it would not go into forward, first discovered when backing out of a slip which made for an interesting evolution. We had it rebuilt with no issue.

Maybe I have a grounding problem on the 4.154 but the aluminum cooler only seems to last a year or two. I now have several, and try to catch the corrosion before it gets to bad. Then I clean up the cooler and rebuild it with aluminum epoxy that I buy from Cotronics. Works really well.

Regards,

Dave
s/v Air Ops
Maramu #104

On Dec 18, 2017, at 7:50 AM, James Alton lokiyawl2@... [amelyachtowners] <amelyachtowners@...> wrote:

Mike,

   My Maramu has a plate mounted just in front of the shift lever warning to never leave the transmission in Fwd. gear while sailing.  My boat has a fixed 20” (?) 3 blade prop which can produce a large amount of torque when sailing at higher speeds.  I am guessing that since your prop feathers(so produces little torque if any when feathered)  that it may not matter as much which gear you use but apparently due to the design the Reverse gear is stronger and therefore safer to use when locking the prop shaft.  Perhaps others can verify if this would be correct.

   I also read in Foley the these gears seem to last about 1000 hours on average.  The gear on my boat has the same paint as the engine and I don’t see any evidence of it having been replaced.  The engine now has just over 4,000 hours.  Could others comment on the life expectancy the have experienced with the Hurth gears?  My boat appears to have had an aluminum cooler for a very long time,  it may in fact have been original based on the installation.  I replaced the old cooler with a new aluminum one.  The old one was not leaking but when cleaning out the inside I found several pin holes that were only plugged with corrosion so it was overdue.  I just got an email back from Foley saying that they have discontinued selling the stainless coolers and now only sell the aluminum.  I wonder if there were corrosion concerns betwee the aluminum gear case and the stainless coolers.  I will try to find out. 

Best,

James
SV Sueno,  Maramu #220

On Dec 18, 2017, at 11:19 AM, 'Mike Ondra' mdondra@... [amelyachtowners] <amelyachtowners@...> wrote:


Who’d of thought there was so much to know about transmissions and their lubrication! Foley website full of interesting information. On a related topic..
 
Dr.. Diesel Tip #101 at Foley says DO NOT put Hurth trans into forward to stop freewheeling, only reverse.
We have always put the trans in forward to stop the freewheeling and fold the Autoprop when under sail. Given Amels have a “C” drive, does Dr. Diesels Tip apply? Have to pose the question just in case there are opinions among our ranks.
 
Mike Ondra
Aletes SM#240
Falmouth Harbor, Antigua
 
















James Alton
 

Gabriele,

I have not yet visited Columbia.. Your english is fine, no problem. I will post what I find out about the coolers sold by Foley. Thanks for planning to provide the information that you have on a source for the aluminum coolers sometime next year.

That is very interesting that you are asking the spelling of my boat’s name. I have been leaving of the accent since it does not appear anywhere on my Mac keyboard so I assumed that it was unavailable. Since you did ask about this however, I did some research on the internet and found a key sequence that will allow me to type Sueño with the accent. I should have researched this earlier! This is the boats original name, which means Dream in Spanish.

Best,
James
SV Sueño
Maramu #220

On Dec 20, 2017, at 12:12 PM, Gabriele Antolini svsunnyside@... [amelyachtowners] <amelyachtowners@...> wrote:


James,
Sunny Side is at Todomar Yard Cartagena
Your understanding of my bad english is 100% correct.
End of January, I will be on board and I will look for where I ordered my cooler from.
The name of your boat is Sueno or Sueño ?
Regards
Gabriele
SV Sunny Side
Maramu #219


From: "James Alton lokiyawl2@... <mailto:lokiyawl2@...> [amelyachtowners]" <amelyachtowners@... <mailto:amelyachtowners@...>>
To: amelyachtowners@... <mailto:amelyachtowners@...>
Sent: Wednesday, 20 December 2017, 9:29
Subject: Re: [Amel Yacht Owners] Hurth Transmissions freewheeling folding prop


Gabriele,

I am glad that you are having good luck! Thanks for the tip on the Militec-1, what I have read about the product sounds very promising. I will order some and give it a try.

So if I understand you correctly, you changed your aluminum cooler back in 1997 when the engine had 4,000 hours on it, you now have 10,000 hours on your engine and you are still using the same cooler? May I ask where you ordered your cooler from? It seems that some people are having problems with their coolers corroding quickly.

Perhaps our boats were built side by side side since Sueno is #220? May I ask where your boat is now?

Best,

James
SV Sueno
Maramu #220

On Dec 19, 2017, at 4:00 PM, Gabriele Antolini svsunnyside@... <mailto:svsunnyside@...> [amelyachtowners] <amelyachtowners@... <mailto:amelyachtowners@...>> wrote:


Hi James
- Good care : YES , Exceptional care: I do not think so. The only thing I use , that not everyone use , is: MILITEC-1 (everywhere possible, on sea and on land) according to the producer recommendations . Nothing to do with the cooler.
- Cooler : Yes I have the small square aluminum cooler. I changed it on 97 . when I received the boat, with 4,000 hours.
From 99 to 2006 I was living on board using marinas only when could not be evitable. In the last ten years, at the end of my four months sailing season, in April, I ran the engine for one hour with fresh water(half an hour one day and half an hour, one day or two later) .
A little of luck is always welcome.

Gabriele
SV Sunny Side
Maramu #219
From: "James Alton lokiyawl2@... <mailto:lokiyawl2@...> [amelyachtowners]" <amelyachtowners@... <mailto:amelyachtowners@...>>
To: amelyachtowners@... <mailto:amelyachtowners@...>
Sent: Tuesday, 19 December 2017, 12:06
Subject: Re: [Amel Yacht Owners] Hurth Transmissions freewheeling folding prop


Gabriele Anolini,

That is amazing, you must be taking exceptional care of your transmission. Do you have a cooler on your transmission? Foley seems to be saying that 1000 hours is about all that we should expect. It would be nice to know which factors seem to lead to a longer service life.

Happy Holidays,

James

SV Sueno
Maramu #220

On Dec 19, 2017, at 11:25 AM, Gabriele Antolini svsunnyside@... <mailto:svsunnyside@...> [amelyachtowners] <amelyachtowners@... <mailto:amelyachtowners@...>> wrote:


James

I can confirm you that the Hurth 250 transmission can work much more than 4,000 hours. Mine passed 10,000 hours and , still now, never gave me a problem.

Best

Gabriele Antolini
SV Sunny Side
Maramu #219
Todomar Yard Cartagena


From: "James Alton lokiyawl2@... <mailto:lokiyawl2@...> [amelyachtowners]" <amelyachtowners@... <mailto:amelyachtowners@...>>
To: amelyachtowners@... <mailto:amelyachtowners@...>
Sent: Monday, 18 December 2017, 23:42
Subject: Re: [Amel Yacht Owners] Hurth Transmissions freewheeling folding prop


Dave,

Thanks for this information. At least I now know that at least some of the Hurth 250 transmissions installed on Maramu’s are lasting longer than the 4,000 hours that mine has. So far my transmission seems to be working fine but the failure mode that you experienced does not sound like a pleasant to experience so maybe I will do something preemptive before long.

I have heard of others having a problem with their aluminum coolers corroding quickly as well.. Without being bonded, I would think that the aluminum parts immersed in seawater would become the sacrificial items on the engine so maybe that could be part of your problem as you suspect. I am wondering however if there is more than one manufacturer of these coolers with some being made of a more corrosion resistant alloy? The original cooler on my transmission had a plate on it that in large letters had the name Hurth, Monchen, Made in West Germany. The old rusty hose clamps, hoses and the apparent age of the ID plate and mounting bolts suggests to me that this cooler had been on the transmission for a very long time.. The one that I ordered as a replacement and installed this year with all new hoses was sold by “Mr Cool” 3306107001 ZF Transmission/Gear Cooler. The replacement cooler cost $165.00 USD. The Cooler being sold by Foley is much more expensive, $395.00 which comes with a quart of their special synthetic fluid. I think I will inquire and see what they say about the large cost differential. Can you tell me where you have been buying your coolers?

In part over corrosion concerns for my cooler, I have been flushing the engine with fresh water whenever the engine will sit for more than a couple of days which I think should help to reduce the corrosion some. I think that I will open the cooler at least every couple of seasons to see how much corrosion is present.

Best,

James Alton
SV Sueno, #220
Arbatax, Italy

On Dec 18, 2017, at 8:32 PM, David Wallace svairops@hotmail..com <mailto:svairops@...> [amelyachtowners] <amelyachtowners@... <mailto:amelyachtowners@...>> wrote:

James,

Our Hurth 250 started acting up in 2002 with about 6000 hours on the engine. Intermittently it would not go into forward, first discovered when backing out of a slip which made for an interesting evolution. We had it rebuilt with no issue.

Maybe I have a grounding problem on the 4.154 but the aluminum cooler only seems to last a year or two. I now have several, and try to catch the corrosion before it gets to bad. Then I clean up the cooler and rebuild it with aluminum epoxy that I buy from Cotronics. Works really well.

Regards,

Dave
s/v Air Ops
Maramu #104

On Dec 18, 2017, at 7:50 AM, James Alton lokiyawl2@... <mailto:lokiyawl2@...> [amelyachtowners] <amelyachtowners@... <mailto:amelyachtowners@...>> wrote:

Mike,

My Maramu has a plate mounted just in front of the shift lever warning to never leave the transmission in Fwd. gear while sailing. My boat has a fixed 20” (?) 3 blade prop which can produce a large amount of torque when sailing at higher speeds. I am guessing that since your prop feathers(so produces little torque if any when feathered) that it may not matter as much which gear you use but apparently due to the design the Reverse gear is stronger and therefore safer to use when locking the prop shaft. Perhaps others can verify if this would be correct.

I also read in Foley the these gears seem to last about 1000 hours on average. The gear on my boat has the same paint as the engine and I don’t see any evidence of it having been replaced. The engine now has just over 4,000 hours. Could others comment on the life expectancy the have experienced with the Hurth gears? My boat appears to have had an aluminum cooler for a very long time, it may in fact have been original based on the installation. I replaced the old cooler with a new aluminum one.. The old one was not leaking but when cleaning out the inside I found several pin holes that were only plugged with corrosion so it was overdue.. I just got an email back from Foley saying that they have discontinued selling the stainless coolers and now only sell the aluminum. I wonder if there were corrosion concerns betwee the aluminum gear case and the stainless coolers. I will try to find out.

Best,

James
SV Sueno, Maramu #220

On Dec 18, 2017, at 11:19 AM, 'Mike Ondra' mdondra@... <mailto:mdondra@...> [amelyachtowners] <amelyachtowners@... <mailto:amelyachtowners@...>> wrote:


Who’d of thought there was so much to know about transmissions and their lubrication! Foley website full of interesting information. On a related topic...

Dr.. Diesel Tip #101 at Foley says DO NOT put Hurth trans into forward to stop freewheeling, only reverse.
We have always put the trans in forward to stop the freewheeling and fold the Autoprop when under sail. Given Amels have a “C” drive, does Dr. Diesels Tip apply? Have to pose the question just in case there are opinions among our ranks.

Mike Ondra
Aletes SM#240
Falmouth Harbor, Antigua