
Juan de Zulueta
Dear Members,
the engine of my ONAN group on my Super Maramu after one hour is going on security ( engine check). I checked the impeller, the heat exchanger, the main sea water filter , everything looks fine. Does anybody encountered similar problem ?
many thanks in advance.
Juan de Zulueta SM 32 Ophelie X +596 696 98 81 32
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Did you measure the Temperature of the Exhaust Elbow and the Oil Filter?
The oil filter should be about 80C when the Onan has warmed up to operating temperature. And the exhaust elbow about 50C.
If the exhaust elbow is higher than 50C, there is a restriction or limitation of seawater flow. Other than the things you checked, this can be caused by a build-up of carbon in the exhaust manifold and exhaust elbow. Did you visually check the impeller?
Bill
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CW Bill Rouse
Amel Owners Yacht School
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Address:
720 Winnie, Galveston Island, Texas 77550
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On Sun, Jan 10, 2021 at 2:16 PM Juan de Zulueta < jdezulue@...> wrote: Dear Members,
the engine of my ONAN group on my Super Maramu after one hour is going on security ( engine check). I checked the impeller, the heat exchanger, the main sea water filter , everything looks fine. Does anybody encountered similar problem ?
many thanks in advance.
Juan de Zulueta SM 32 Ophelie X +596 696 98 81 32
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Juan de Zulueta
Bill, I changed the impeller but I did not check temperature of the oil neither of the exhaust i am not sure what type of thermometer I can use . I checked coolant level , see water temp, coolant temp in the hoses before and after heat exchanger but only by hand and not using thermometer
thanks again for your answer
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Juan,
You should have something like this. It will help you with many things:
If you have a meat thermometer, it can work. Something like this:
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CW Bill Rouse
Amel Owners Yacht School
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Address:
720 Winnie, Galveston Island, Texas 77550
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toggle quoted messageShow quoted text
On Sun, Jan 10, 2021 at 4:39 PM Juan de Zulueta < jdezulue@...> wrote: Bill, I changed the impeller but I did not check temperature of the oil neither of the exhaust i am not sure what type of thermometer I can use . I checked coolant level , see water temp, coolant temp in the hoses before and after heat exchanger but only by hand and not using thermometer
thanks again for your answer
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Juan de Zulueta
Bill,
I have indeed an infrared medical thermometer. I will use it to check. I was as well wondering if my problem could come from the thermostat? I am currently in Antigua do yo know if there is a Onan dealer selling spare parts in Antigua ? I did not find any on the website of Cummins Onan. Juan de Zulueta +33680895892 sent from my Ipad.
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Le 10 janv. 2021 à 19:17, CW Bill Rouse <brouse@...> a écrit :
Juan,
You should have something like this. It will help you with many things:
If you have a meat thermometer, it can work. Something like this:
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CW Bill Rouse
Amel Owners Yacht School
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|
|
Address:
720 Winnie, Galveston Island, Texas 77550
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On Sun, Jan 10, 2021 at 4:39 PM Juan de Zulueta < jdezulue@...> wrote: Bill, I changed the impeller but I did not check temperature of the oil neither of the exhaust i am not sure what type of thermometer I can use . I checked coolant level , see water temp, coolant temp in the hoses before and after heat exchanger but only by hand and not using thermometer
thanks again for your answer
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Juan de Zulueta
Bill,
I did checked the temperature of the exhaust elbow and oil filter : exhaust elbow temp is 41,5 C oil filter 79,5 C
these seems OK according to your rec. any other idea ? Could this come from the water temp switch shutoff S2 ?
best regards
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Juan,
Contact David Walter in Jolly Harbour:
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CW Bill Rouse
Amel Owners Yacht School
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|
|
Address:
720 Winnie, Galveston Island, Texas 77550
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|
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toggle quoted messageShow quoted text
On Mon, Jan 11, 2021 at 6:42 AM Juan de Zulueta < jdezulue@...> wrote: Bill,
I have indeed an infrared medical thermometer. I will use it to check. I was as well wondering if my problem could come from the thermostat? I am currently in Antigua do yo know if there is a Onan dealer selling spare parts in Antigua ? I did not find any on the website of Cummins Onan. Juan de Zulueta +33680895892 sent from my Ipad. Le 10 janv. 2021 à 19:17, CW Bill Rouse <brouse@...> a écrit :
Juan,
You should have something like this. It will help you with many things:
If you have a meat thermometer, it can work. Something like this:
|
CW Bill Rouse
Amel Owners Yacht School
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|
|
Address:
720 Winnie, Galveston Island, Texas 77550
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On Sun, Jan 10, 2021 at 4:39 PM Juan de Zulueta < jdezulue@...> wrote: Bill, I changed the impeller but I did not check temperature of the oil neither of the exhaust i am not sure what type of thermometer I can use . I checked coolant level , see water temp, coolant temp in the hoses before and after heat exchanger but only by hand and not using thermometer
thanks again for your answer
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Juan,
Also, Bill Kinney may still be there in Jolly Harbour aboard an Amel Super Maramu RASCAL. Bill Kinney may be able to help you before he leaves. +1415-488-6755 greatketch@.... Bill will be the best person with the most experience. If Bill & Karen have left, David Walter in my previous email.
Bill
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CW Bill Rouse
Amel Owners Yacht School
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Address:
720 Winnie, Galveston Island, Texas 77550
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toggle quoted messageShow quoted text
On Mon, Jan 11, 2021 at 11:25 AM Bill Rouse < brouse@...> wrote: Juan,
Contact David Walter in Jolly Harbour:
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CW Bill Rouse
Amel Owners Yacht School
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|
|
Address:
720 Winnie, Galveston Island, Texas 77550
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On Mon, Jan 11, 2021 at 6:42 AM Juan de Zulueta < jdezulue@...> wrote: Bill,
I have indeed an infrared medical thermometer. I will use it to check. I was as well wondering if my problem could come from the thermostat? I am currently in Antigua do yo know if there is a Onan dealer selling spare parts in Antigua ? I did not find any on the website of Cummins Onan. Juan de Zulueta +33680895892 sent from my Ipad. Le 10 janv. 2021 à 19:17, CW Bill Rouse <brouse@...> a écrit :
Juan,
You should have something like this. It will help you with many things:
If you have a meat thermometer, it can work. Something like this:
|
CW Bill Rouse
Amel Owners Yacht School
|
|
|
Address:
720 Winnie, Galveston Island, Texas 77550
|
|
|
On Sun, Jan 10, 2021 at 4:39 PM Juan de Zulueta < jdezulue@...> wrote: Bill, I changed the impeller but I did not check temperature of the oil neither of the exhaust i am not sure what type of thermometer I can use . I checked coolant level , see water temp, coolant temp in the hoses before and after heat exchanger but only by hand and not using thermometer
thanks again for your answer
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karkauai
Hi Juan, Thank you for answering my post about transmission . I had a similar issue with my ONAN shutting down and found that the sensor on the exhaust elbow was faulty. I had a spare and was back underway in a short time. Some Onans have a normally closed temp switch that opens when the temp is too high. If you have that kind, and don't have a spare, short the two sensor wires and it should start. If you have the normally open switch that closed when the temp gets too high, you can disconnect the sensor and it should start. In either case, regularly check the temps at your oil filter and exhaust whenever running it until you can get a replacement.
Hope that's the problem on your Onan, easy fix. Kent SM 243 Kristy -- Kent & Iris
KRISTY
SM243
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Juan de Zulueta
Hi Kent,
Thanks for your advise. Next time my Onan will shut down i will try to short circuit the exhaust sensor or the coolant sensor to identify the origin of the pb.
Best regards
Juan de Zulueta Ophelie X SM 32 Envoyé de mon iPhone
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Le 11 janv. 2021 à 14:53, karkauai via groups.io <karkauai@...> a écrit :
Hi Juan, Thank you for answering my post about transmission . I had a similar issue with my ONAN shutting down and found that the sensor on the exhaust elbow was faulty. I had a spare and was back underway in a short time. Some Onans have a normally closed temp switch that opens when the temp is too high. If you have that kind, and don't have a spare, short the two sensor wires and it should start. If you have the normally open switch that closed when the temp gets too high, you can disconnect the sensor and it should start. In either case, regularly check the temps at your oil filter and exhaust whenever running it until you can get a replacement.
Hope that's the problem on your Onan, easy fix. Kent SM 243 Kristy -- Kent & Iris
KRISTY
SM243
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Juan,
Over the years of production, some Onan generators have Normally Closed (NC) sensors and other Onans have Normally Open sensors (NO). Just because some other Super Maramu had NC sensors does not mean that your SM has the same. Attached is a page from my Amel Book that explains some of this.
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CW Bill Rouse
Amel Owners Yacht School
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Address:
720 Winnie, Galveston Island, Texas 77550
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toggle quoted messageShow quoted text
On Mon, Jan 11, 2021 at 1:03 PM Juan de Zulueta < jdezulue@...> wrote: Hi Kent,
Thanks for your advise. Next time my Onan will shut down i will try to short circuit the exhaust sensor or the coolant sensor to identify the origin of the pb.
Best regards
Juan de Zulueta Ophelie X SM 32 Envoyé de mon iPhone Hi Juan, Thank you for answering my post about transmission . I had a similar issue with my ONAN shutting down and found that the sensor on the exhaust elbow was faulty. I had a spare and was back underway in a short time. Some Onans have a normally closed temp switch that opens when the temp is too high. If you have that kind, and don't have a spare, short the two sensor wires and it should start. If you have the normally open switch that closed when the temp gets too high, you can disconnect the sensor and it should start. In either case, regularly check the temps at your oil filter and exhaust whenever running it until you can get a replacement.
Hope that's the problem on your Onan, easy fix. Kent SM 243 Kristy -- Kent & Iris
KRISTY
SM243
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