Forum Discussion
- garyemunsonExplorer IIThe float valve is leaking and flooding the engine with gas. You see external leakage but there is also plenty going into the cylinder drowning out the spark plug. Usual cause is not running the generator dry of gas prior to end of season storage. Gasoline does not completely evaporate and leaves deposits behind that both plug up the tiny jet holes that regulate gas flow through the carburetor and also prevents the needle valve from completely closing and shutting off gas flow when the float reaches the proper level. While they can be cleaned, very few mechanics actually understand carburetor function enough anymore to successfully do that and consequently replacement is the preferred course of action. If your generator does not have a gas line shutoff, you can wrap the jaws of a pair of vice grips with electrical tape so it won't cut the hose and use it to pinch the fuel line shut so you can run the generator out of gas next time and prevent this from repeating next year. An alternative strategy is to "man up" and camp all through the winter so the generator is used regularly! Something else to consider is that after fixing the carburetor issue, you really need to change the oil and filter again as it has gotten diluted by the excess gasoline that was in the cylinder and snuck it's way past the piston rings. Running the generator with gas-thinned oil will ruin the bearings.
- midnightsadieExplorer IIX2 great advise.
- Dutch_12078Explorer IIIf the generator is exercised monthly for 45-60 minutes under load as Onan recommends, it will not gum up and any moisture in the windings or light corrosion on the slip rings will be removed.
- Dave_H_MExplorer IIMy daddy always was a believer in taking a medium to large screwdriver and use the plastic handle to tap on the side of the carb in an effort to unstick the float/needle/and seat. :W
It appears that you may be able to take that carb off and clean it or replace it.
BTW, as far as a fuel shut off, I would recommend an easy install of a aftermarket valve stuck in that flex fuel line. - ksg5000ExplorerIf I paid someone to do all that work on my generator and it came back with that problem I would return the RV and expect him to fix it for free.
- wa8yxmExplorer IIICarb rebuild, as the other poster said Float valve (needle valve) Not closing.
I had this happen on a big Dodge V8 Back in the days. Turns out it was a fuel pump problem, as the pump diaphram failed it flaked off and the flakes got into the needle valve. so the problem is very likely related to the replacement of fuel pump and filter. A bit of debris was knocked loose and got in the valve.
Carb clean and rebuild and you should be 100%.. May need to just clean the needle valve. - WTrippeExplorerHe took some things apart. There was fluid in this plastic floater piece. Anyone know where I can get this replacement floater?
- KpackpackkelleyExplorer IIWhat’s the model number of the generator ?
- WTrippeExplorer
Kpackpackkelley wrote:
What’s the model number of the generator ?
Onan MicroQuiet 4000. Model 4KYFA261OOK Serial A070013571 - maillemakerExplorerAnother thing that can cause fuel flooding of the carburetor is if you have a fuel pump that is generating too much pressure. This can happen if the original pump was replaced with an incorrect pump that produces too much pressure. On my Onan 4BGEF the pump must only produce 3-5 PSI, as I recall. Standard automotive fuel pumps can deliver much more and the carb might not be able to hold it back.
Steve
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