Don't ya just love Onans?

[fissioneng]

I have been gradually chasing problems with an 8 kw MDKD that is new to me (1986 vintage). Last Fall, I fixed the cooling system by changing the RW impeller, a hose, acid cleaned the heat exchanger, and changed the thermostat. That appears to have fixed my cooling problem which was causing the high temp switch to shutdown the unit.

I ran it occasionally all winter with no problems, but recently, it ran for 2 hours, then suddenly shutdown, and then wouldn´t start. No reset button trip (temp, oil, exhaust switches). I waited a week, then it started and ran for a total of 15 hours at different times with no issues. Last weekend, it started and ran for 45 minutes and stopped. No reset button trip. It will momentarily start and then stops. The stop solenoid is engaging like it should and I can hear the start relay clicking on and off like it should. There is plenty of oil and coolant.

I have not changed the fuel filters on this unit yet. I have a 10 micron Racor and a 2 micron Racor on the unit. Is it possible that these filters are so clogged that the unit won´t run? Would it cause this intermittent running/not running? Could the filters unclog by sitting a week?

Other than fuel, all I can think of is the engine monitor or regulator going bad, but I would think if they went bad, the unit wouldn´t run at all and not have this intermittent behavior. Is there anything else I´m missing?

[SKYCHENEY]

It could stop because of the filters based on load. When the load is high and it needs more fuel, it gets starved.

[Canuck Dennis]

If the start solonoid stays in, it is most likely that you have fuel problems, change all fuel filters, clean the bowls if applicable.

[captddis]

Check the Facet pump. They can do this. There is also a filter in the bottom of the fuel pump.

[shark 1007]

I had a similar issue with mine of the same vintage and replaced the fuel pump with one of those inline 50 buck ones from Discount auto parts and all was cured.

[Trojan]

Check the fuel pump there are 2 check valves inside and they have the tendency to come loose from there socket. I disassembled My pump. Cleaned and reseated the checks using J&B weld. Been working for 3 years now'

BILL

[Boatsb]

If the valves in the pump get lose they can flip over and is a pita.I reseated them with a thin aluminum band and they stayed put for the last 100 hours.

[fissioneng]

Anyone know what model Facet pump I might have? The Onan number is 149-1828. Onan price is about $250, the Facet is less than half that.

I will certainly pull the filter out of it and check it, and also look at the check valves.

[fissioneng]

Answer from an old thread

http://www.samsmarine.com/forums/showthread.php?t=9453

Facet #42370

[fissioneng]

Can't be right. That number is a filter kit.