Kohler 6.5 on 1994 390CPMY shuts doen

[tonyiiiafl]

Choke plate appears to be functioning properly. When I start from cold it will shut for 3 or 4 seconds, open and close again until it fires off. SO it that is a fuel recovery line, I would assume the excess or recovered gas will go back to the air cleaner to be burnt again?

[tonyiiiafl]

am really starting to think the capacitor is a bit at fault also. It stared fine this AM, ran about 2 hours, a little surge here and there, but I also saw the amp meter go from where it was at load, to “0” then back again. Now a few moments ago, I saw the meter at “0” and could hear thee contractors buzzing, like they were trying to pull in, but couldn’t. I did replace the contractors last year and once I get back, will check the secondary gas filter, and then replace the capacitor with the spare I carry.

[bud37]

Source of the post Choke plate appears to be functioning properly. When I start from cold it will shut for 3 or 4 seconds, open and close again until it fires off. SO it that is a fuel recovery line, I would assume the excess or recovered gas will go back to the air cleaner to be burnt again?

Just so I am clear here.....are you saying the choke plate is staying wide open while the engine is running ?? If so then all is well, but it should not flop around.

Regarding the amp meter.....is this going to zero coinciding with the surge ?

Really just crossing some things off the list. The capacitor sounds quite promising, but engine surging ( hunting ) is generally a sign of lean fuel or could be a governor issue ( the spring gets old, tension not quite right ). So there is a need to cross some things off.....gets tough when there are multiple different red flags leading to the same end result.

[tonyiiiafl]

The choke plate opens and closes as the gen set cranks. Seems normal as when it kicks to start it will open, the shut if it does not start from cold. Sadly, the amp meter does not coincide with the surge. IF I put a substantial load on it, ie water heater and AC it seems to work fine.

As for the capacitor, I have seen where Kohler did come out with recommendation of a 26uf capacitor. I have two of those coming. I think the plan of attack will be:( and I will try it after each step.)
New Air filter
Replace capacitor
Replace governor spring
Voltage regulator

then shoot myself in the foot.

OH yeah, my port alternator, which was new also decided to take a holiday.

[bud37]

Tony you can adjust the spring a little by just disconnecting one end and turning the spring one turn and reconnecting.....makes a small amount more tension as the spring gets shorter......don't go overboard, just tiny adjustments, but new would be great.

Good grief it really is tough to get good product nowadays isn't it......

[KeithS]

The little hose goes to the bottom of a sump on the front of the carb. Because it is a side draft carb, if it floods, fuel would spill out causing a safety hazard. The sump catches the fuel and feeds it back into the intake manifold.
The choke is a little different on that model. There is an electric solenoid, a thermo-switch and a choke control board. When the engine is cold, the choke is full on until the engine starts. When the engine is warm the choke kind of flutters on and off. This is because when the engine is cranking, the mechanical governor is holding the throttle wide open and the engine has low vacuum through the carb trying to draw fuel. The fluttering choke is needed to start even when the engine is warm. That generator was never real happy with the Carver auto-transfer switch. The governor must be set to 63hz at no load and the 25mfd capacitor was recommended. It is a quirk of a capacitor excited generator that a heavy load makes better output. The CZ models were Kohler's attempt at a low cost brushless generator. They went back to brushes on the later models as it just worked better than the capacitor excited model for them.
As interesting as all that is, I don't think that is your problem. It sounds more like a fuel problem. When it starts to surge, try manually holding the choke on a little and see if it smooths out. Carburator issues are pretty common because the passageways and jets are so small and the ethanol fuel doesn't help.

[tonyiiiafl]

Good point, I will check that when it starts to surge. I don’t think the carb was ever off.