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  2. SM 2000 head backflow and holding tank leak -second attempt

SM 2000 head backflow and holding tank leak -second attempt

Mike Ondra
 

From ALETES, SM#240 1999 with Jabsco manual pump: Head backflow and Holding Tanks

We have persistently had issues with holding tank backflow to the toilet requiring frequent cleaning or replacement of the joker valve. Additional measures have included the addition of a Jabsco check valve as well as the installation of the “locking” version of the Jabsco manual pump. Three layers of defense could not defeat the backflow problem, apparently due to buildup of crystals on all the backflow preventive devices.  

Also, we have experienced leakage at the connections of the riser hoses (both inlet and outlet) where they connect to the tank. As others have noted, that connection on some models is a copper sleeve that is glassed into the tank, and that copper corrodes over time developing pin-holes and associated leaks. Nasty. Band-aid fixes over the years usually held for a time, but the corrosion keeps on working and leaks reappear.

During our latest effort at cleaning and replacing the valves we had a surprise. As anyone who has removed the riser pipe that connects the pump to the tank knows, the contents of the entire riser drain out. Hence it is prudent to flush with a significant volume of water prior to attempting the disconnect. By doing so, the contents that spill into the shower pan are “mostly” clean water.  In this last removal, however, the contents of the ENTIRE holding tank spilled into the shower pan (no further description required). So now we are apparently dealing with a third holding tank issue. Time for a major effort in holding tank repair.

The internal workings of the holding tank have always been a bit of mystery as there is no access port and the 3 openings to the tank are rather small, basically 1.5”. We have not seen shop drawings or photos of the interior of the tank, but from BB postings, our understanding has been that from the copper sleeve penetrating the fiberglass there is a riser tube in the tank that delivers the waste and spills somewhere near the top of the tank. So before developing a plan of attack for repairs, we removed the deck plate to get slightly larger access to the tank to see what was inside and perhaps determine the problem. Here are the long-awaited photos of the inside of the tank looking down from the deck plate. 

    

So as one can see, the copper sleeve also corroded within the tank and ultimately the riser extension within the tank separated from it. Wastes were being pumped into the BOTTOM of the tank, and any disconnection of the riser hose in the inboard side would drain any remaining contents within the tank above the drain sump. One curiosity is why the riser within the tank would loop up and then back down so that the discharge point is low in the tank. We couldn’t see but presume there is no vacuum breaker at the top of the loop, so as soon as the contents level would be above the discharge end of the loop, the riser would not drain itself, and in fact become a siphon for backflow. Anyway, since it seemed attached to the tank wall and/or top and we could not get into the tank to disconnect, we could not remove it and it was abandoned in place. NOTE TO OTHERS who have experienced the corrosion of the copper sleeve below the tank - this failure within the tank may be in your future as well.

Mark Erdos on May 3, 2017 posted an excellent description of his fix for the inboard portion of the copper pipe corrosion while leaving the upper copper pipe and its connection within the tank in place. This was not an option for us due to the separation above. So, following his procedure but completely removing the copper, our solution was a continuous piece of sanitary hose from check-valve near the pump all the way to the top of the holding tank, no connections to leak.

    

We reamed out the hole in the fiberglass with rotary rasp so the tubing would slip through. Flared the top of the hole a bit to receive epoxy resin that would seal around the tubing and ooze down between the tube and the fiberglass. Putty was placed around the internal end of the joint to prevent the epoxy from running out. The resin was delivered to the flared opening at the top of the tube/fiberglass joint by pouring it down a PVC pipe/straw.

   

After curing we filled the tank with clean water to test for leaks. There seemed to be none. However, overnight there was evidence of a slight leak. We suspect there was insuffient gap between the tube and the fiberglass for the somewhat viscous resin to fully flow and fill. Otherwise, this solution seems good. So now the plan is to remove the tube, ream out the fiberglass a bit more to achieve, say, a 2mm gap between them and once again fill with resin.

Any comments, experiences, words of wisdom appreciated as we plan for this FINAL fix.

Mike Ondra, ALETES SM#240, Rock Hall, MD

 

 

 

 

 

 
Craig Briggs
 

Hi MIke,
Although ours is an SN, without the notorious SM corroding copper sleeve, I plumbed my aftermarket holding tanks with 1 1/2" PVC pipe 20 years ago. Annual or so doses of HCl keep the interior mineral build up at bay and rubber flexible couplings at the deck and through hull fitting eliminate vibration issues with the rigid glued pipe structure. Imho, far superior than even the most expensive hose that sewage permeates with smells after a few years. PVC never permeates odors (well, at least for the last 20 years).
Good luck with your project.
Craig 
Alan "Woody" Wood
 

Nice write-up Mike
A task that will inevitably zoom up the jobs list when that leak appears.
We were looking at compost toilet options recently..  no more valves, holding tank or backflow. Seems almost too good to be true - but people who have them swear by them!
Cheers
Woody
Mike Ondra
 

High Woody.

Can’t say I know much about composting toilets in boats. I can say that I was in the composting toilet business (Clivus Multrum) for probably 10 years back in the 70’s with hundreds installed in homes and public places. These were large volume slow process composters no way suitable to boats. Perhaps the new small composters with heat produce more rapid decomposition and dehydration.

Best of luck.

Mike

ALETES SM#240 – Rock Hall, MD

 

From: main@AmelYachtOwners.groups.io <main@AmelYachtOwners.groups.io> On Behalf Of Alan "Woody" Wood
Sent: Tuesday, June 23, 2020 9:50 AM
To: main@AmelYachtOwners.groups.io
Subject: Re: [AmelYachtOwners] SM 2000 head backflow and holding tank leak -second attempt

 

Nice write-up Mike
A task that will inevitably zoom up the jobs list when that leak appears.
We were looking at compost toilet options recently..  no more valves, holding tank or backflow. Seems almost too good to be true - but people who have them swear by them!
Cheers
Woody

Mark Erdos
 

Perhaps the biggest issue with the compost heads I see is the ability to find the fresh peat moss or coconut fiber needed to make the compost. The whereabouts seems to be a common question asked on various FB groups in places we’ve traveled. 

 

 

With best regards,

 

Mark

 

Skipper

Sailing Vessel - Cream Puff - SM2K - #275

Currently cruising - Tahiti, French Polynesia

www.creampuff.us

 

From: main@AmelYachtOwners.groups.io [mailto:main@AmelYachtOwners.groups.io] On Behalf Of Alan "Woody" Wood
Sent: Tuesday, June 23, 2020 3:50 AM
To: main@AmelYachtOwners.groups.io
Subject: Re: [AmelYachtOwners] SM 2000 head backflow and holding tank leak -second attempt

 

Nice write-up Mike
A task that will inevitably zoom up the jobs list when that leak appears.
We were looking at compost toilet options recently..  no more valves, holding tank or backflow. Seems almost too good to be true - but people who have them swear by them!
Cheers
Woody

CW Bill Rouse
 

This is a personal opinion: I do not believe that compost toilets and Amels go together.

This is a personal rant that I have previously expressed: Since no Amel was ever produced with a compost toilet, possibly the Prime Directive should be considered.

This is a professional opinion: Let me assure you that you will have difficulty selling that composted Amel at the time that you need to sell her, and, unless she sinks, there will be a time in the future to sell her.

This is a joke: Composted boats just don't smell right.

Bill
CW Bill Rouse Amel Owners Yacht School
Address: 720 Winnie, Galveston Island, Texas 77550 
View My Training Calendar


On Tue, Jun 23, 2020 at 12:27 PM Mark Erdos <mcerdos@...> wrote:

Perhaps the biggest issue with the compost heads I see is the ability to find the fresh peat moss or coconut fiber needed to make the compost. The whereabouts seems to be a common question asked on various FB groups in places we’ve traveled. 

 

 

With best regards,

 

Mark

 

Skipper

Sailing Vessel - Cream Puff - SM2K - #275

Currently cruising - Tahiti, French Polynesia

www.creampuff.us

 

From: main@AmelYachtOwners.groups.io [mailto:main@AmelYachtOwners.groups.io] On Behalf Of Alan "Woody" Wood
Sent: Tuesday, June 23, 2020 3:50 AM
To: main@AmelYachtOwners.groups.io
Subject: Re: [AmelYachtOwners] SM 2000 head backflow and holding tank leak -second attempt

 

Nice write-up Mike
A task that will inevitably zoom up the jobs list when that leak appears.
We were looking at compost toilet options recently..  no more valves, holding tank or backflow. Seems almost too good to be true - but people who have them swear by them!
Cheers
Woody

James Alton
 

Mike,

   I have built a few custom holding tank systems for boats (Not yet on an Amel) that have so far proven reliable.  I think that the most important step if you want to minimize problems is to eliminate ALL metal in the system that is exposed to the corrosive contents.  Polyester/glass will work,  Epoxy/Glass is better IMO because Epoxy does a better job to contain odours and is not as prone to water absorption.    I also apply a barrier coating on the inside of the tank prior to closing it.  It may not be essential to add a barrier coating since I build the tanks I have built used epoxy resin but I tend to go with belts and suspenders on these kinds of projects!    The suggestion of using hard PVC pipe to reduce odours is a good one and far superior to using hose, even the best sanitation hose.  If you want to take it a step further you can use fibreglass pipe that can be fibreglassed right to the tank, eliminating a lot of the leak prone joints. You can buy polyester/fiberglass exhaust pipe in various sizes and a few shapes.  The pipe is a little thin I think..   While you can bond some materials such as PVC to a fibreglass tank, the bond is quite poor structurally as compared to properly joining two compatible pcs. of fibreglass.  It’s not hard to cut a fibreglass pipe if needed for service in the future and either glass it back together with wraps of glass tape/epoxy  or in a pinch you can put in a length of hose until more permanent repairs can be made.  While time consuming compared to the normal methods of running hose,  it is possible to make custom epoxy fibreglass piping to the exact non clogging  (gentle curves)  shapes desired and to make them strong which is my preferred method.  I like to make the pipe walls about as thick as the tank and glass the joints together.   All of the tank input pipes that I have installed come in at the very top of the tank with no downward extension.  I am not sure why the pipe apparently extended to the bottom of your tank which as you suggest would appear to create a siphon effect, keeping pressure on your back flow devices.   Sorry for the problems,  best of luck in finding a solution that works for you.

James

   

On Jun 8, 2020, at 8:42 PM, Mike Ondra via groups.io <mdondra@...> wrote:

From ALETES, SM#240 1999 with Jabsco manual pump: Head backflow and Holding Tanks

We have persistently had issues with holding tank backflow to the toilet requiring frequent cleaning or replacement of the joker valve. Additional measures have included the addition of a Jabsco check valve as well as the installation of the “locking” version of the Jabsco manual pump. Three layers of defense could not defeat the backflow problem, apparently due to buildup of crystals on all the backflow preventive devices.   

Also, we have experienced leakage at the connections of the riser hoses (both inlet and outlet) where they connect to the tank. As others have noted, that connection on some models is a copper sleeve that is glassed into the tank, and that copper corrodes over time developing pin-holes and associated leaks. Nasty. Band-aid fixes over the years usually held for a time, but the corrosion keeps on working and leaks reappear.

During our latest effort at cleaning and replacing the valves we had a surprise. As anyone who has removed the riser pipe that connects the pump to the tank knows, the contents of the entire riser drain out. Hence it is prudent to flush with a significant volume of water prior to attempting the disconnect. By doing so, the contents that spill into the shower pan are “mostly” clean water.  In this last removal, however, the contents of the ENTIRE holding tank spilled into the shower pan (no further description required). So now we are apparently dealing with a third holding tank issue. Time for a major effort in holding tank repair. 

The internal workings of the holding tank have always been a bit of mystery as there is no access port and the 3 openings to the tank are rather small, basically 1.5”. We have not seen shop drawings or photos of the interior of the tank, but from BB postings, our understanding has been that from the copper sleeve penetrating the fiberglass there is a riser tube in the tank that delivers the waste and spills somewhere near the top of the tank. So before developing a plan of attack for repairs, we removed the deck plate to get slightly larger access to the tank to see what was inside and perhaps determine the problem. Here are the long-awaited photos of the inside of the tank looking down from the deck plate.  

<image018.png>  <image019.png>  <image020.png>

So as one can see, the copper sleeve also corroded within the tank and ultimately the riser extension within the tank separated from it. Wastes were being pumped into the BOTTOM of the tank, and any disconnection of the riser hose in the inboard side would drain any remaining contents within the tank above the drain sump. One curiosity is why the riser within the tank would loop up and then back down so that the discharge point is low in the tank. We couldn’t see but presume there is no vacuum breaker at the top of the loop, so as soon as the contents level would be above the discharge end of the loop, the riser would not drain itself, and in fact become a siphon for backflow. Anyway, since it seemed attached to the tank wall and/or top and we could not get into the tank to disconnect, we could not remove it and it was abandoned in place. NOTE TO OTHERS who have experienced the corrosion of the copper sleeve below the tank - this failure within the tank may be in your future as well.

Mark Erdos on May 3, 2017 posted an excellent description of his fix for the inboard portion of the copper pipe corrosion while leaving the upper copper pipe and its connection within the tank in place. This was not an option for us due to the separation above. So, following his procedure but completely removing the copper, our solution was a continuous piece of sanitary hose from check-valve near the pump all the way to the top of the holding tank, no connections to leak. 

<image021.png>    <image022.png>

We reamed out the hole in the fiberglass with rotary rasp so the tubing would slip through. Flared the top of the hole a bit to receive epoxy resin that would seal around the tubing and ooze down between the tube and the fiberglass. Putty was placed around the internal end of the joint to prevent the epoxy from running out. The resin was delivered to the flared opening at the top of the tube/fiberglass joint by pouring it down a PVC pipe/straw. 

<image023.png>   <image022.png>

After curing we filled the tank with clean water to test for leaks. There seemed to be none. However, overnight there was evidence of a slight leak. We suspect there was insuffient gap between the tube and the fiberglass for the somewhat viscous resin to fully flow and fill. Otherwise, this solution seems good. So now the plan is to remove the tube, ream out the fiberglass a bit more to achieve, say, a 2mm gap between them and once again fill with resin. 

Any comments, experiences, words of wisdom appreciated as we plan for this FINAL fix.

Mike Ondra, ALETES SM#240, Rock Hall, MD

 

 

 

 

 

 
Mike Ondra
 

Thanks James. This is good information.

Epoxying in a fiberglass tube riser will be my next/third attempt… if the sanitary hose solution doesn’t hold up.

Regards,

Mike

ALETES SM#240

 

From: main@AmelYachtOwners.groups.io <main@AmelYachtOwners.groups.io> On Behalf Of James Alton via groups.io
Sent: Tuesday, June 23, 2020 2:50 PM
To: main@AmelYachtOwners.groups.io
Subject: Re: [AmelYachtOwners] SM 2000 head backflow and holding tank leak -second attempt

 

Mike,

 

   I have built a few custom holding tank systems for boats (Not yet on an Amel) that have so far proven reliable.  I think that the most important step if you want to minimize problems is to eliminate ALL metal in the system that is exposed to the corrosive contents.  Polyester/glass will work,  Epoxy/Glass is better IMO because Epoxy does a better job to contain odours and is not as prone to water absorption.    I also apply a barrier coating on the inside of the tank prior to closing it.  It may not be essential to add a barrier coating since I build the tanks I have built used epoxy resin but I tend to go with belts and suspenders on these kinds of projects!    The suggestion of using hard PVC pipe to reduce odours is a good one and far superior to using hose, even the best sanitation hose.  If you want to take it a step further you can use fibreglass pipe that can be fibreglassed right to the tank, eliminating a lot of the leak prone joints. You can buy polyester/fiberglass exhaust pipe in various sizes and a few shapes.  The pipe is a little thin I think..   While you can bond some materials such as PVC to a fibreglass tank, the bond is quite poor structurally as compared to properly joining two compatible pcs. of fibreglass.  It’s not hard to cut a fibreglass pipe if needed for service in the future and either glass it back together with wraps of glass tape/epoxy  or in a pinch you can put in a length of hose until more permanent repairs can be made.  While time consuming compared to the normal methods of running hose,  it is possible to make custom epoxy fibreglass piping to the exact non clogging  (gentle curves)  shapes desired and to make them strong which is my preferred method.  I like to make the pipe walls about as thick as the tank and glass the joints together.   All of the tank input pipes that I have installed come in at the very top of the tank with no downward extension.  I am not sure why the pipe apparently extended to the bottom of your tank which as you suggest would appear to create a siphon effect, keeping pressure on your back flow devices.   Sorry for the problems,  best of luck in finding a solution that works for you.

 

James

 

   

On Jun 8, 2020, at 8:42 PM, Mike Ondra via groups.io <mdondra@...> wrote:

 

From ALETES, SM#240 1999 with Jabsco manual pump: Head backflow and Holding Tanks

We have persistently had issues with holding tank backflow to the toilet requiring frequent cleaning or replacement of the joker valve. Additional measures have included the addition of a Jabsco check valve as well as the installation of the “locking” version of the Jabsco manual pump. Three layers of defense could not defeat the backflow problem, apparently due to buildup of crystals on all the backflow preventive devices.   

Also, we have experienced leakage at the connections of the riser hoses (both inlet and outlet) where they connect to the tank. As others have noted, that connection on some models is a copper sleeve that is glassed into the tank, and that copper corrodes over time developing pin-holes and associated leaks. Nasty. Band-aid fixes over the years usually held for a time, but the corrosion keeps on working and leaks reappear.

During our latest effort at cleaning and replacing the valves we had a surprise. As anyone who has removed the riser pipe that connects the pump to the tank knows, the contents of the entire riser drain out. Hence it is prudent to flush with a significant volume of water prior to attempting the disconnect. By doing so, the contents that spill into the shower pan are “mostly” clean water.  In this last removal, however, the contents of the ENTIRE holding tank spilled into the shower pan (no further description required). So now we are apparently dealing with a third holding tank issue. Time for a major effort in holding tank repair. 

The internal workings of the holding tank have always been a bit of mystery as there is no access port and the 3 openings to the tank are rather small, basically 1.5”. We have not seen shop drawings or photos of the interior of the tank, but from BB postings, our understanding has been that from the copper sleeve penetrating the fiberglass there is a riser tube in the tank that delivers the waste and spills somewhere near the top of the tank. So before developing a plan of attack for repairs, we removed the deck plate to get slightly larger access to the tank to see what was inside and perhaps determine the problem. Here are the long-awaited photos of the inside of the tank looking down from the deck plate.  

<image018.png>  <image019.png>  <image020.png>

So as one can see, the copper sleeve also corroded within the tank and ultimately the riser extension within the tank separated from it. Wastes were being pumped into the BOTTOM of the tank, and any disconnection of the riser hose in the inboard side would drain any remaining contents within the tank above the drain sump. One curiosity is why the riser within the tank would loop up and then back down so that the discharge point is low in the tank. We couldn’t see but presume there is no vacuum breaker at the top of the loop, so as soon as the contents level would be above the discharge end of the loop, the riser would not drain itself, and in fact become a siphon for backflow. Anyway, since it seemed attached to the tank wall and/or top and we could not get into the tank to disconnect, we could not remove it and it was abandoned in place. NOTE TO OTHERS who have experienced the corrosion of the copper sleeve below the tank - this failure within the tank may be in your future as well.

Mark Erdos on May 3, 2017 posted an excellent description of his fix for the inboard portion of the copper pipe corrosion while leaving the upper copper pipe and its connection within the tank in place. This was not an option for us due to the separation above. So, following his procedure but completely removing the copper, our solution was a continuous piece of sanitary hose from check-valve near the pump all the way to the top of the holding tank, no connections to leak. 

<image021.png>    <image022.png>

We reamed out the hole in the fiberglass with rotary rasp so the tubing would slip through. Flared the top of the hole a bit to receive epoxy resin that would seal around the tubing and ooze down between the tube and the fiberglass. Putty was placed around the internal end of the joint to prevent the epoxy from running out. The resin was delivered to the flared opening at the top of the tube/fiberglass joint by pouring it down a PVC pipe/straw. 

<image023.png>   <image022.png>

After curing we filled the tank with clean water to test for leaks. There seemed to be none. However, overnight there was evidence of a slight leak. We suspect there was insuffient gap between the tube and the fiberglass for the somewhat viscous resin to fully flow and fill. Otherwise, this solution seems good. So now the plan is to remove the tube, ream out the fiberglass a bit more to achieve, say, a 2mm gap between them and once again fill with resin. 

Any comments, experiences, words of wisdom appreciated as we plan for this FINAL fix.

Mike Ondra, ALETES SM#240, Rock Hall, MD

 

 

 

 

 

 

 
Randall SV ALBEDO
 

Woody the simple answer is, Don't do it.
I have just fixed my forward head issue and would recommend all boaters regularly put decalcifiers in the tanks. I have started using Harpic 10, a toilet bowl cleaner with 10% hydrochloric acid. The crustacean build up needs to be dealt with in a preventive way.
Too many butts on a boat will get you many "but dad it smells"

Randall
A54#56
Still in Gib.

Virus-free. www.avg.com


On Tue, Jun 23, 2020 at 3:50 PM Alan "Woody" Wood <woody@...> wrote:
Nice write-up Mike
A task that will inevitably zoom up the jobs list when that leak appears.
We were looking at compost toilet options recently..  no more valves, holding tank or backflow. Seems almost too good to be true - but people who have them swear by them!
Cheers
Woody

Paul Dowd and Sharon Brown
 

Presumably this applies only if you use sea water for flushing?

 

Cheers,

Paul

S/Y Ya Fohi - Amel 54 #98 - Grenada

 

From: main@AmelYachtOwners.groups.io <main@AmelYachtOwners.groups.io> On Behalf Of Randall
Sent: 24 June 2020 09:36
To: main@amelyachtowners.groups.io
Subject: Re: [AmelYachtOwners] SM 2000 head backflow and holding tank leak -second attempt

 

Woody the simple answer is, Don't do it.

I have just fixed my forward head issue and would recommend all boaters regularly put decalcifiers in the tanks. I have started using Harpic 10, a toilet bowl cleaner with 10% hydrochloric acid. The crustacean build up needs to be dealt with in a preventive way.

Too many butts on a boat will get you many "but dad it smells"

 

Randall

A54#56

Still in Gib.

 

Virus-free. www.avg.com

 

On Tue, Jun 23, 2020 at 3:50 PM Alan "Woody" Wood <woody@...> wrote:

Nice write-up Mike
A task that will inevitably zoom up the jobs list when that leak appears.
We were looking at compost toilet options recently..  no more valves, holding tank or backflow. Seems almost too good to be true - but people who have them swear by them!
Cheers
Woody


--
Cheers
Paul
Ya Fohi - Amel 54 #98
Robert Nilsen
 

What a brilliant tip!
I have the same problem with a collapsed riser pipe in the forward holding tank, and will plan for glassing in a new glassfiber or epoxy pipe. 
Due to still lockdown wher my boat is, I'm not there to measure dimension of piping, but belive it's 38mm.
Can anyone confirm that? 

Best regards Robert 
S/Y Silfrania 
SM#53
Mike Ondra
 

Robert,
On Aletes it is 1.5” copper, concurring with your 38mm.
Mike


On Jun 24, 2020, at 8:38 AM, Robert Nilsen <robert@...> wrote:

What a brilliant tip!
I have the same problem with a collapsed riser pipe in the forward holding tank, and will plan for glassing in a new glassfiber or epoxy pipe. 
Due to still lockdown wher my boat is, I'm not there to measure dimension of piping, but belive it's 38mm.
Can anyone confirm that? 

Best regards Robert 
S/Y Silfrania 
SM#53

Robert Nilsen
 

Thanks :-)

best regards
Robert
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