john deere 316 surges

[jbc8000]

Hi there, i have a 316 with a p218 onan in it. My problem is that the motor surges when sitting still. At varies throttle position it surges up and down. Runs great while mowing, it just seems to do it when its sitting there. Any thoughts or ideas.

 

[joe csuti]

Check for dirt/water in carb bowl & dirt in main jet & idle/low speed passages in carb body,plugged/restricted idle/low speed passages will make eng surge/hunt for it's speed

 

[jbc8000]

Those were my thoughts, have had it apart about three or four times pass two days, and still is doing it. Cleaned carb, jets, bowl, new fuel filter. Seems to do it more so once engine is warm.

 

[Dude11]

There's a tiny o-ring on you main carb.jet;if not perfect(new)that may be your tro.BTW-the ones you get at auto parts stores don't work nearas well as one for an Onan.There's also a problem with fiber floats,save yourself some headaches and get a brass one.The fiber ones tend to swell and won't let fuel enter bowlas needed via needle & seat.dude11

 

[jbc8000]

k i will check the o ring and see about a new one and set of the brass floats, when it surges there is more that enough fuel in the bowl. Can smell it and see some "popping" out of the carb. So maybe the floats are sticking down and not letting the needle come all the way down. What if i gentle just knock on the side of the bowl with it surging, if its the floats they should come up if sticking and maybe help narrow it down?

 

[Anonymous-0]

Check the intake manifold for air leaks. The manifolds are two piece units and often leak. If leaking you will have to remove the manifold and reseal with rtv.

 

[Dude11]

I not sure if tapping it will tell you much.Mine was doing all kinds of stuff,the o-ring and new type float did the trick.BTW with the breather off,mine will spit alittle gas also,I think that's normal.Joe is right about the idling thing(he always is---sharp guy,he's helped me many times over the years)dude11

 

[Anonymous-0]

It could be as simple as the governor spring. Try one hole further from the shaft.

 

[joe csuti]

Thanks for the compliment dude,as the mind get's older,memory get's shorter,I usually take my best guess from things I still remember & problems/fix's I've used in past.

 

[DaveK(IN)]

I had the same problem, checked many of the carb/fuel issues and it turned out to be in intake manifold. When I had the rpms up for cutting it seemed to "suck" it up against the gasket surface some but the rest of the time it surged. It had become loose.

 

[jbc8000]

when checking my main jet again, there was no o ring that came off with it. So ill pick a new one up and try that