Re: [Amel] Re: Strange problem with ONAN ---missing information

Richard03801 <richard03801@...>

Hi all be very careful regarding engine rpm's over or under will change the voltage an Hz out put that may do other damage. Note the run position of the lever and mark it. You may also want to use a tachometer to test and set.


Richard Piller

Cell 603 767 5330

On Dec 21, 2012, at 7:41, "Judy and Bill aboard SV BeBe" <yahoogroups@...> wrote:


There is some missing information in this thread because there were some private emails exchanged between myself and Alessandro.

I am sure that there are a few of you that would like to see that exchange, so I have pasted it here:

Thank so much...I 'd try a new (fuel) pump BUT when Onan stopped no flashing code appears...
This is a strange thing!

One more thing I thought of for a shutdown without a code:

Try this:
Go to the fuel injection pump and you should see a little lever that gets pulled by a small solenoid. That solenoid may be going bad. See if the solenoid is pulling or dropping out when the engine starts, then shut down.

This solenoid has two coils. One is 12VDC for starting and the other is 4VDC which holds the solenoid after starting. The 4 volt coil may be going bad. When you hold the start button down, the alarms are bypassed and the 12VDC coil on the solenoid is energized. When you release the start button, the 4VDC coil on the solenoid is energized and keeps the solenoid closed.

Try holding the lever with your hand, or mechanically keeping it in a "run position" by tying or wiring it in position. If the Onan continues to run, you need to replace this solenoid. I believe that if this solenoid fails you will receive no code.

Additionally, regarding the impeller blades:
If you did not get a shutdown code, the impeller was probably not the source of your shutdown because if your shutdown was due to overheating or lack of water flow, you would see a flashing code.

The best way that I have found to simply remove all of the impeller blades from the Onan Heat Exchanger is to close the main sea chest valve and open the end caps on both ends of the Heat Exchanger...while using a wet/dry shop vacuum (shop-vac) to suck the excess water and the blade parts which will end up in the vacuum. If you turn on the shop-vac as you loosen the end caps, you will capture all of the water and have zero water clean-up.

This would also be a great time to change the zinc on the Heat Exchanger.

Unfortunately, if you do not have a wet/dry shop-vac, you will need to remove the Heat Exchanger to get all of the pieces out. Removing the Exchanger is problematic with all of its connections, so buy or borrow a shopvac. Also, the end caps and end cap gaskets are delicate and may get damaged in this process. It is a good idea to keep end cap spares on-board.

Hope this solves your problem...let me know.

BeBe, SM2k, #387

--- In amelyachtowners@..., "Judy and Bill aboard SV BeBe" <yahoogroups@...> wrote:

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.



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

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

--- In amelyachtowners@..., "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!!!!

Supermaramu 2k #443
Rodney bay - st lucia

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