Onan Generator On a Trojan Tri-Cabin

[Punx]

I know these things are a little finicky... But for the life of me I can't figure this out...

Two days ago: In the breaker box / switch panel I set the power selector to "Gen", I flipped the top generator switch to the on position. The exhaust fan ran for about 5 minutes then the generator kicked in. It sounded like any engine should, and produced enough power for the entire boat without hesitation. after 30 seconds, the lights dimmed and the generator slowly sputtered out. It would not start up again.

Now, I follow the exact same routine, the fan blows, stops, and then nothing. There's absolutely no noise coming from the generator. When I flip the switch on the actual generator from auto to ON, I still don't get anything. Is there anything i can do to manually start the generator, or at least diagnose the problem?

Note: The lights and fridge were on to draw power from the system.

[sdowney717]

On my Onan with the automatic starting, there is a thermal circuit breaker that has to be reset if the thing wont start within a certain period of time. it pops out, and you push it back in.
I have an on-off-on switch mounted in the box, down is turn on, middle is off, up is turn on if it detects a demand load like a light or the fridge turns on.

If you push that back in and it still wont crank over could be one of the relays.

[sdowney717]

I posted the mcck onan manual I had online right here
lots of info you can read up on it.
Onan MCCK Manual

I went thru the electric start up sequence for this a long time ago and here is what it does.

I also had to replace the transistor on the automatic start sense control board.
the way that works is it sends a 12 volt signal onto the AC wires, when it senses a current demand it auto starts the generator. On mine, the bilge blower circuit control is disabled so no starting delay.

[sdowney717]

Here is the installation manual for the onan mcck
Onan Installation Manual Marine Generator

[Punx]

Wow you're awesome! thanks a lot!

We got it started but the sequence seems pretty random. I'm definitely going to do some reading!

[CarlF]

"Sputtering out" is usually fuel related including air in the fuel (you might have had a different issue later when nothing would start). I would replace all fuel filters and filter gaskets. Onan gensets are great but their fuel pump is not very strong.

Carl

[sdowney717]

Yes, fuel pump failed on mine, diaphragm got a hole.
And it has breaker points which can get dirty.

parts for these are still available.

And some things can be made to work, you dont have to use the original coil. someone posted they were needing a new coil, but any 12 volt car coil will work. Just have to make it fit. The coil fires both plugs at the same time. One set of points and no distributor. Shielded plugs bronze wire mesh on the wires for spark suppression. I guess radio noise and gas explosion issues, but your main engines use regular spark plugs and wires.

I think these are pretty neat gensets, very quiet and smooth.