Generator runs for a few seconds then stops

[RV-Ron]

Sent: 9/26/2003

My 4kw Onan Genset starts, runs for a few seconds, then stops.  Anybody have any tips on how to correct this?    It starts well, just doesn't run for very long.

[Boat Nut]

Sent: 9/26/2003 

Hi Ron,
Sometimes they will do that because of low oil level. I believe there is a shutdown on oil temperature, and when the oil is low it gets hot quick.

Chuck

[denisondc]

Sent: 9/26/2003

Do you know how old the genset is?
My guess would be a fuel flow problem, a restriction or blockage somewhere. If it has an electric fuel pump I would start by disconnecting the fuel supply right at the carb, and see if the electric pump is able to keep fuel pouring out, and let it pump a while, catching it in a large can. Not that it couldn't be a blockage in the carb somewhere.
If it were an ignition problem I would expect it to either not start, or run long enough to get warmed up - minutes, not seconds. denison

[jbrt1989]

Sent: 9/26/2003

It could be the low oil sensor.  But, most generators I've dealt with won't start at all if the oil is too low.

I suppose it could have just enough oil to start cold, but, once it gets going and sending oil thru the motor, the level could drop low enough to trigger the shutdown sensor.

I would check the oil, even change it if not been changed in awhile.  If you don't know how long it's been, change it anyway to be safe.  If that doesn't work, I'd start looking at the fuel system.  Clogged fuel filter, line,. pump not giving enough pressure, etc.  Something along those lines. 

I too doubt it could be anything in the ingition, for the most part that either works or it doesn't.  It's unlikely the ignition would cause a good smooth start and run then shut off in my experience

The only other thing I can think of could be the carburator.  But, since I've not dealt with that yet, I'll let those who know more about them help you there.

Jeff

[Dave-Pam1]

Sent: 9/26/2003 

RV Ron,

Mine did this once because of the vent hoses were plugged with dirt...Run a coat hanger or stiff wire up them to make sure.
David

[RV-Ron]

Sent: 9/27/2003

Thanks, Chuck.   I've checked the oil for this purpose, and even change it with synthetic oil.   Today I will dig further into this problem, and hopefully get it resolved.

Thanks again for the tip.

[RV-Ron]

Sent: 9/27/2003

This genset was original, in an '84 Winnabago 22'.  I too suspect a fuel problem, and today I will change the filter.  I purchased this several months ago, and have been refurbishing it quite extensively.  The generator is the last item to tackle--and the motorhome is in excellent shape. 

Thank you for your input, and I will look forward to future contacts on similar issues.

Ron--Utah

[RV-Ron]

Sent: 9/27/2003

I've ruled out the oil, and suspect it may be a plugged fuel line.  I'll change the filter today and see what that does.  If a carburetor problem, like you--I have little successful experience, but will soon be an expert.  I've enjoyed refurbishing this motor home so much that I am tearing everything apart just to learn more about how these things work.

Thanks for the advice, and I hope to be able to return the favour soon.

Ron--Utah

[78winniejdubbrave]

Sent: 7/6/2004

Guys-

If you have an Onan genset w/points spend the extra $ and get the Onan electronic ignition conversion kit an have it professionally instaslled. It is the ONLY way to go. Better starts and no cleaning/checking after storage.

[Sea Hag]

Sent: 7/6/2004 

How much does the conversion kit cost and where did you get it from ? I'm sure I can install it myself . - Sea Hag 

[HeavyHaulTrucker]

Sent: 7/9/2004

Uh... you might also want to check the points.  I know, sounds strange... but mine acted up the other day.  Hard to start, started but run only seconds, etc.  I was tearing my hair out trying to figure out why... until I pulled the cover for the points, and watched them while trying to turn over the engine.  The PO had put in a new set of points, gapped them, but had not tightened the screw enough -- engine vibration had loosened it enough that they had moved so that there was no gap.  Once I re-gapped them and tightened down the screw properly, she fired right up and ran along happily.

John

[Wendell]

Sent: 7/23/2004 

I'm having a similar problem.  The genset manual says to turn the engine over by hand to get the points on the high point on the cam.  I have a lot of experience working with engines, but none working with gensets.  How do you turn the engine over by hand?  Everything seems to be so closed in, I don't see anywhere to turn the flywheel or anything.

[440charlie]

Sent: 7/23/2004

check fuel in tank the genny feeds from  on mine if fuel is below half a tank genny shuts off --this keeps you from getting stranded someplace [out of gas] mine a dodge 440 feeds from right tank   hope its that simple for yours        C  P

[HeavyHaulTrucker]

Sent: 7/24/2004

I just use the switch on the genset to "bump" the engine until the points are open -- then I make my adjustment.

John

[HeavyHaulTrucker]

Sent: 7/24/2004 

440Charlie, that is a possibility.  Mine runs out when the aux tank is at 1/4 tank -- gives you enough to make a getaway when you run out in the boonies.

John

[Sea Hag]

Sent: 7/24/2004 12:35 PM

If the genny stops after a few seconds after you relase the start sitch . The manual says to hold the start button down for a few seconds after it starts to let the 12volt side of the genny  supply power to the ign. - as the 12volt for ign. is tmporarilly supplied by the batt for starting and is removed hen you relase the switch . The starter is accutally the generator it's self  so you won't hurt it by holding down . Sea Hag