Generator won't start

[georgetown50]

I'm a full-timer in the RV and the maintenance manual said to run the generator for 1 hour every month. I must have skipped this too long because now I can't seem to get the generator started. I've tried starting from both the inside and the outside. A couple of times it did finally start but within 5 minutes stopped and then wouldn't start back up again.

1. Any suggestions on getting it started?

2. How worried should I be that it won't start? I ask this because I don't really use the generator except to do this monthly maintenance just to keep things going.

[NO3putt]

I would get it going, you never know when the RV park will have a power outage or needing to run the AC while going down the road. Hopefully someone with more generator knowledge will be able to help.

[Phil57]

Just by chance how much fuel do you have on board? Less than a quarter and it won't run.

[kenandterry]

I've been having a problem with my genny for awhile.

It is a Generac brand 6500. It was working fine for a few years until it began having troubles. Sometimes it starts okay, runs for a few minutes okay, and then will start to over rev from it's normal speed. I'm not about to leave it run at the higher speed and see if it will correct itself........kinda leery of an explosion, so I turn it off.

Other times, it tries to start twice then abandons the effort. This sequence is normal according to documentation followed by a pattern of light flashing on the control pattern indicating it's fault. According to mine, it flashes that is "underspeed". Not sure what that means, as the cranking speed to try startup is always the same.

Gasoline level is not the issue........can be full, 1/2 tank or anywhere in between.

Obviously no service center can speculate the repair costs ahead of having the unit at their location.

[georgetown50]

Originally Posted by Phil57

Just by chance how much fuel do you have on board? Less than a quarter and it won't run.

It's got at least a half tank. I'll keep trying.

[willingtonpaul]

gasoline begins to degrade over time and gums up the carburator. it gets thick like shellac and causes the carb's ability to regulate fuel flow and throttle position to not function properly. ethanol blends make this worse by adding excess moisture, now creating rust in addition to residue. my guess is that you let the genny sit so long that the fuel in the genny and lines to it began to degrade, and now the carb needs to be cleaned. one of the reasons it is recommended that you run the genny for an hour is to get complete fuel flow from the tank to flush the entire line with fresh tank fuel. that and to bring the genny up to temp to heat the oil to remove moisture from it and other side benefits to the generator part of the unit to remove moisture there. in my TT and 5'er days i carry portable gennys, and i run them out of fuel at the end of the season for winter storage, and i use stabil in the fuel during the camping season. you can't run the genny out of fuel in your coach; it will still have fuel in the lines after the auto cut off if the main tank is too low. if you are parked in one spot for an extended period of time, i would even go so far as to add stabil to your fuel tank with a fill up right before you park; if i was full timing and parked somewhere for 4-5 months in the winter, let's say, i would add an appropriate amount of stabil to the tank and fill it before i parked so there would be no issues at the end of the season. i would still exercise the genny every couple of weeks, though.

if i am correct and this is the issue, the carb needs to be cleaned. if servicing the genny is not your cup of tea, i would have it serviced to get the generator up and running properly. just running it now won't fix it; the carb needs to be cleaned and re-adjusted for it to run properly again. then, religiously run it once every couple of weeks for an hour (i think a monthly interval is too long, personally).

it is too valuable of a piece of equipment to not have running properly. also, a well serviced / well running genny helps the coach hold resale value.

[Still Kickin]

All good advice. Since you have spark, its a fuel delivery issue. I agree with getting new fuel to the carb, to see if it will start. Otherwise, sounds like you need a carb cleaning.
I once had gas stored in a fuel can that was two years old. I couldn't even light it with a match, it had lost that much volatility.

[Paul S.]

You may have more of a governor issue than a carb issue. The governor linkage controls the carb throttle. When the engine is off or cranking the governor linkage holds the throttle fully opened. Once the engine starts the governor adjusts the throttle linkage to hold a predetermined rpm. If you now put a load on it the governor linkage compensates for the load. Remove the load and it again compensates. If your governor linkage is sticking due to dirt, rust, or something made a nest around it then you could have these symptoms. I have a exmark zeroturn lawn mower and my linkage occasionally sticks because this mower is kept out in the weather. It will overspeed when I disengage the blade and it will not come down to idle even when moving the hand throttle. I know I have a rust issue and need to lube the linkage occasionally. It seems like your linkage might be sticking.

[mshell56118]

Willing to bet brushes are dirty on generator. Cummins onan will have those symptoms and usually is the brushes. They are easy to clean once accessible which is a totally different story. My rec is take it in


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[Cyclone Rich]

I had this exact same issue on my previous RV (1998 Fleetwood Bounder) and I got advice from my Bounder Forum that worked, so I figured I'd share it here.

There is a rubber fuel line that runs from the generator to the main fuel tank, and over time that line will develop cracks and lose the ability to create the proper suction.

I bought a couple feet of brand new fuel line, disconnected the line at the fuel pump, and then ran that new line into a fresh gas tank (mower gas can). The Generator fired right up and ran like a champ.

I hired a mobile mechanic to come to my house, drop the fuel tank, and install a new fuel line. Been running good ever since. (I sold it last year and bought a Georgetown 351DS a couple months ago)

[Jack Durney]

Had the same problem with mine called FR extended warranty and got it fixed it was a bag fuel pump !

[SnowBird9]

Put some fuel stabilizer in the tank when you are going to leave the RV in storage for a while. I use almost a whole bottle. It keeps the generator in top shape.

[RamblerGuy]

The Onan on our motor home has a drain on the carburetor. A paper towel is enough to catch the gas that drains out.

[gmann32]

After you have drained the carb also put a new fuel filter in. It is a inline filter and I would guess 1/4 or 5/16" fuel line. Get it at any mower shop.