"Gummed" v. "Clogged" generator carburetor....

[S.Rodimus]

My other potentially dumb question for the day:
I have been told that a generator with a "clogged" carburetor won't start up at all. Is there a difference between a "gummed up" carburetor and a "clogged" one -- as in one will start, run, then stall; while the other won't start up at all? Or are "gummed up" and "clogged" just synonyms?

[Morich]

There are small passages in the carb and they can get gunk on the sides or they can get totally stopped! Gummed might say things pass gas through but not to all parts or easily, while clogged might be just a bit more to totally stop flow?
But the difference is not all that much as either needs to be cleaned and possibly adjusted to run right!

[S.Rodimus]

Originally Posted by Morich

There are small passages in the carb and they can get gunk on the sides or they can get totally stopped! Gummed might say things pass gas through but not to all parts or easily, while clogged might be just a bit more to totally stop flow?
But the difference is not all that much as either needs to be cleaned and possibly adjusted to run right!

Yeah, I'm thinking that I phrased my question wrongly (I said "clogged") to the person who told me it wouldn't start up at all. Because ours does start -- then run, then stall out. Maybe I should have instead asked them the symptoms of a "gummed up" carb.

Hoping to get confirmation here from more people who know.

We do plan to clean the carb regardless; and if that doesn't work, replace the carb entirely.

[creativepart]

Originally Posted by S.Rodimus

We do plan to clean the carb regardless; and if that doesn't work, replace the carb entirely.

Careful on the “replace” part of this. We’ve had a number of folks here post that Onan OEM cabs are very difficult to purchase and that there are many replacement carbs online made in Asia that fit and look the part but either don’t work right or at all. One recently said he bought a non-Onan carb and to get it to work he had to tear apart both the OEM carb and the new carb and build a hybrid of both units.

Are you aware that Cummins owns Onan and most Cummins shops can troubleshoot and repair your generator.

[S.Rodimus]

Originally Posted by creativepart

Careful on the “replace” part of this. We’ve had a number of folks here post that Onan OEM cabs are very difficult to purchase and that there are many replacement carbs online made in Asia that fit and look the part but either don’t work right or at all. One recently said he bought a non-Onan carb and to get it to work he had to tear apart both the OEM carb and the new carb and build a hybrid of both units.

Are you aware that Cummins owns Onan and most Cummins shops can troubleshoot and repair your generator.

Yes, we are aware. Any replacement work will be done by a professional. We are just exhausting all the cheaper options that we can perform ourselves before we start spending real money on this issue.

[moabdds]

Most of the current ethanol gasoline available will gum up your carb if it sits too long without running. Mine did, and I called the Onan service center (100 miles away) and they said they do not clean the carbs, but would replace it for $$$. I found a local small engine repair guy who, for much less money, pulled the carb out, took it home, disassembled it and cleaned it up. I don't remember if he was able to clean the jet or if he had to replace it, but it works like a charm now. He told me I needed to run it for about 1/2 hour at least once a month to prevent the problem from happening again. Every first Sunday of each month, I go out and crank up the generator for about 1/2 hour. It's been two years since the fix and have had no problems since. He also told me I could install a shut-off valve in-line (like on a motorcycle) and when I was putting the rig away for an extended time, to shut off the valve and then run the generator until it died so there would be no gas in the bowl to evaporate and gum it up. Then I wouldn't need to run it every month. I have not done that, though.

[CABender]

I have a vintage car that was giving me problems that pointed to the carburetor. Much like a camper generator it was not used regularly. Someone suggested fuel additive "Star Tron". After the first use it was like a miracle! No more sputtering, no hesitation when accelerating from an idle. It was like a brand new car. Can't guarantee similar results, but it worked for me and sure beat the price of cleaning, rebuilding, or replacing the carburetor.

[Bobn1957]

Originally Posted by moabdds

Most of the current ethanol gasoline available will gum up your carb if it sits too long without running. Mine did, and I called the Onan service center (100 miles away) and they said they do not clean the carbs, but would replace it for $$$. I found a local small engine repair guy who, for much less money, pulled the carb out, took it home, disassembled it and cleaned it up. I don't remember if he was able to clean the jet or if he had to replace it, but it works like a charm now. He told me I needed to run it for about 1/2 hour at least once a month to prevent the problem from happening again. Every first Sunday of each month, I go out and crank up the generator for about 1/2 hour. It's been two years since the fix and have had no problems since. He also told me I could install a shut-off valve in-line (like on a motorcycle) and when I was putting the rig away for an extended time, to shut off the valve and then run the generator until it died so there would be no gas in the bowl to evaporate and gum it up. Then I wouldn't need to run it every month. I have not done that, though.

There might be a plug on the bottom of the carb you can remove to drain the fuel out!

[Morich]

I don't think we can blame ethanol for fuel clogs as they have been around nearly forever!
Fuel of any sort will have bits and pieces of "stuff" that won't burn and if the good stuff dries out, the junk is left to clog anything it can find!

When I was leaving for service and thought I would be back in a few months to use the car, I drained the gas and disconnected the carb to avoid having to redo it when I got
back.
It took more like three years to get back to that car but the carb was still good!

There are a lot of products that claim to clear the gunk and it would be worth the low cost to try them but newer carbs are more complex and more fussy, so how much to expect is a question. Cheap enough to try for me.

Maybe just add some to the RV tank and see if it help there for better mileage, etc. on both?

[Ray,IN]

Clogged means no flow, gummed-up means reduced flow + restricted movement of moving parts