Strange problem with ONAN


alexgennai <agennai@...>
 

My boat is a SUPERMARAMU 2k #443 lunched 2004
I just crossed atlantic and during passage Onan worked perfectly for 6h/day for 15days but the 16th day began to "cough" and stopped: I check Racor were ok, I changed fuel filter, But I found impeller broker and so I changed it!
BUT, anyway, after that my ONAN works well for just 20 minutes than starts "coughing" and stops! Now I''m in St lucia and here mechanic can't solve the problem so I'm here asking your help if someone could give us an idea....I'd appreciate all suggestions!!!!

Saluti
Alessandro
GRAND CRU
Supermaramu 2k #443
Rodney bay - st lucia


Judy and Bill aboard SV BeBe <yahoogroups@...>
 

Alessandro,

What error code are you getting? The error code is a series of blinking lights on the start switch.

From your description I would guess that the Onan is either starving for fuel, or there is a faulty 12VDC connection.

A few things to consider in order of priority:
If the electric fuel pump is failing, it could intermittently deliver insufficient pressure and starve the Onan of fuel. Be sure that the fuel pump is operating correctly before going to the next step. BTW, the electric fuel pump will eventually fail. If you do not have a spare, now is the time to buy one to determine if this is your problem. If you have a problem with a new one installed, proceed to the next step which will be much more difficult. If the new fuel pump works for you, buy a second one for a spare, if you plan to cross additional oceans.

The Onan will shut down if the 12VDC current is interrupted for even 1 second. This includes both the ground and positive wire. Generally the most suspect parts for intermittent 12VDC current faults are the positive and the negative solenoids.

Check out "Onan DC Control Schema" at http://groups.yahoo.com/group/amelyachtowners/photos/album/1489622282/pic/list?mode=tn&order=ordinal&start=1&dir=asc

Hope this helps. Please let me know what you find.

Bill
BeBe, SM2k, #387

--- In amelyachtowners@yahoogroups.com, "alexgennai" <agennai@...> wrote:

My boat is a SUPERMARAMU 2k #443 lunched 2004
I just crossed atlantic and during passage Onan worked perfectly for 6h/day for 15days but the 16th day began to "cough" and stopped: I check Racor were ok, I changed fuel filter, But I found impeller broker and so I changed it!
BUT, anyway, after that my ONAN works well for just 20 minutes than starts "coughing" and stops! Now I''m in St lucia and here mechanic can't solve the problem so I'm here asking your help if someone could give us an idea....I'd appreciate all suggestions!!!!

Saluti
Alessandro
GRAND CRU
Supermaramu 2k #443
Rodney bay - st lucia


seafeverofcuan <seafeverofcuan@...>
 

Alessandro,
if it is an overheating problem the yellow light at the start and stop switch either in the galley or on the generator should flash one single continual signal flash which means overheating. This will only happen after the generator has been running and overheated and stopped. If you touch the switch at all after that it will clear the signal.
If you have checked in the seawater side of the heat exchanger, meaning take off the round end cap on the port side and not found any missing rubber pieces then take off the sea water pump, it is only two bolts and easy to remove. Be sure and close the grey seawater strainer on the starboard side where the red handle is first.
Look inside the outflow pipe of the pump and make sure that there are no rubber pieces stuck in there.
The slightest little water or electrical hiccup will stop the generator. Be sure to reopen the sea water strainer after you put the pump back on and start the generator.
I have never got more than 120 hours from a genuine Onan impeller they need to be inspected and changed often.
Good luck.

Trevor Lusty
Sea Fever of Cuan
Super Maramu
Nicaragua

--- In amelyachtowners@yahoogroups.com, "alexgennai" <agennai@...> wrote:

My boat is a SUPERMARAMU 2k #443 lunched 2004
I just crossed atlantic and during passage Onan worked perfectly for 6h/day for 15days but the 16th day began to "cough" and stopped: I check Racor were ok, I changed fuel filter, But I found impeller broker and so I changed it!
BUT, anyway, after that my ONAN works well for just 20 minutes than starts "coughing" and stops! Now I''m in St lucia and here mechanic can't solve the problem so I'm here asking your help if someone could give us an idea....I'd appreciate all suggestions!!!!

Saluti
Alessandro
GRAND CRU
Supermaramu 2k #443
Rodney bay - st lucia


Judy and Bill aboard SV BeBe <yahoogroups@...>
 

All concerned,

Alessandro emailed me directly and stated that he was getting a 33 code. He says that 33 is not in his owner's manual. I do not remember what codes are on the switch and in the manual. Since I am off the boat, I looked it up on-line and found 33 is an Onan overheat code. I emailed him and advised him to try cleaning his exchanger.

Best,

Bill
BeBe

--- In amelyachtowners@yahoogroups.com, "seafeverofcuan" <seafeverofcuan@...> wrote:

Alessandro,
if it is an overheating problem the yellow light at the start and stop switch either in the galley or on the generator should flash one single continual signal flash which means overheating. This will only happen after the generator has been running and overheated and stopped. If you touch the switch at all after that it will clear the signal.
If you have checked in the seawater side of the heat exchanger, meaning take off the round end cap on the port side and not found any missing rubber pieces then take off the sea water pump, it is only two bolts and easy to remove. Be sure and close the grey seawater strainer on the starboard side where the red handle is first.
Look inside the outflow pipe of the pump and make sure that there are no rubber pieces stuck in there.
The slightest little water or electrical hiccup will stop the generator. Be sure to reopen the sea water strainer after you put the pump back on and start the generator.
I have never got more than 120 hours from a genuine Onan impeller they need to be inspected and changed often.
Good luck.

Trevor Lusty
Sea Fever of Cuan
Super Maramu
Nicaragua

--- In amelyachtowners@yahoogroups.com, "alexgennai" <agennai@> wrote:

My boat is a SUPERMARAMU 2k #443 lunched 2004
I just crossed atlantic and during passage Onan worked perfectly for 6h/day for 15days but the 16th day began to "cough" and stopped: I check Racor were ok, I changed fuel filter, But I found impeller broker and so I changed it!
BUT, anyway, after that my ONAN works well for just 20 minutes than starts "coughing" and stops! Now I''m in St lucia and here mechanic can't solve the problem so I'm here asking your help if someone could give us an idea....I'd appreciate all suggestions!!!!

Saluti
Alessandro
GRAND CRU
Supermaramu 2k #443
Rodney bay - st lucia