generator is hunting violently

[ShaggyTheGreat]

Recently tried to start my gas generator, not military but I figure you guys can help anyway. I started it with the choke on and then flipped over to run and it hunts rpm violently. Basically from an idea to full speed back to idle. I then took the choke and put it on about 90% and it clears right up. Put the choke all the way on it acts like it always does when you put the choke on all the way. Low rpm running crappy. I took off the carb and cleaned all the Jets. Put it back on still same thing. I haven't touched the adjuster screws so I'm kinda out of ideas. I let it run for a while and it didn't clear up.

 

[gimpyrobb]

Some hunt like crazy without a load. Have you tried running anything off it?

 

[ShaggyTheGreat]

No it used to run with no load just fine.

 

[ShaggyTheGreat]

This generator is about 7 years old and it never did this before this winter.

 

[quickfarms]

What model and make of generator with what engine.

Sounds like you have an issue with the governor and or voltage regulator. The smaller ones are fixed but the larger ones are variable.

 

[dependable]

Some units have a 'wax motor' involved in RPM control as well. If no one can help you here, go over to Smokstak (antique engine and tractor forum) and go to the generator sub-forum. Lots help there. Be sure to state make and model and pictures if possible, or you won't get as much help.

The fact the choke smooths it out makes me think it is probably fuel related.

 

[ShaggyTheGreat]

It's a husky 5kw with a Robin/Subaru ex 30 engine. I am tempered to get rid of it for something like a mep002a if I see one pop up around me for the right price

 

[ShaggyTheGreat]

Some units have a 'wax motor' involved in RPM control as well. If no one can help you here, go over to Smokstak (antique engine and tractor forum) and go to the generator sub-forum. Lots help there. Be sure to state make and model and pictures if possible, or you won't get as much help.

The fact the choke smooths it out makes me think it is probably fuel related.

I cleaned out the carb as well I could but still no fix. That's what I thought but I guess I might have not gotten all the junk out.

 

[dependable]

It could be clogged fuel filter, line or air leak in line as well as carb with that symptom. Am not familiar with that motor, or it has a fuel pump or gravity feed. Has been discussed on the Stak though.

 

[ShaggyTheGreat]

Sounds like a pain to diagnose. Think I can use the choke to make it run through this upcoming storm.

 

[dependable]

Very unlikely to run at stable RPM that way, so you know. Maybe time to get a new one from store if you really need it and don't want to sort this one out. If you think this problem on this generator is a pain, suggest you not get an MEP-002a.

 

[ShaggyTheGreat]

Very unlikely to run at stable RPM that way, so you know. Maybe time to get a new one from store if you really need it and don't want to sort this one out. If you think this problem on this generator is a pain, suggest you not get an MEP-002a.

Not so much the work itself I just don't Wana spend time fixing a hunk I bought as a temporary fix Anway. What kind of issues we to the mep's have? I have done a whole lot of research into that.

 

[dangier]

The fact that the choke smooths it out tells me that it is fuel related. You still have something blocking the passages in the carb. The carb needs to come completely apart to insure you get to all the little passages. Some have welsh plugs (expandable) that have passages underneath. You can get them out, but they are a bear to get back in and sealed. If you are daring, you might want to get a carb rebuild kit and go to it. If you have any small engine shops locally, you might want to check with them about getting the carb rebuilt.
David

 

[barefootin]

It is definitely a fuel issue. How old is the fuel? Was it fresh or left in? If left in or in a can that has been sitting for more than a few months, try some fresh. My engine on my log splitter is very picky. It will hunt if I use e10 gas over a month old it will require more choke the hotter it gets until it literally shuts off. Dump in fresh mid to premium grade and it will run smooth as can be with the choke in. My wife's Cub Cadet tractor is the same. If you leave it sit for a month or two (typical because it rarely makes it through 2 to 3 mowing's without being pulled back into the barn with my tractor) it will only start on full choke, run on partial choke and hunts like crazy. Mix in some fresh gas or drain the tank and it will run as it should... Now both of these problem children will run great even on aged non-ethanol fuel, this however is getting harder to find in my area. If your tank is fresh, I'd pull the carb again or try a little cleaner like sea foam in the tank and leave it run (no load) for a little while with the choke on so it doesn't hunt and see if it clears up.

 

[ShaggyTheGreat]

Well at the moment I'm looking at first attaching an ax fuel tank with fresh fuel. If that does not fix it I will wait out this storm and go after it once I won't need it for a while. I think I will disassemble the carb and clean it up good. I have dug up a service manual for the engine that explains how the carb is disassembled and reassembled.

 

[ShaggyTheGreat]

It is definitely a fuel issue. How old is the fuel? Was it fresh or left in? If left in or in a can that has been sitting for more than a few months, try some fresh. My engine on my log splitter is very picky. It will hunt if I use e10 gas over a month old it will require more choke the hotter it gets until it literally shuts off. Dump in fresh mid to premium grade and it will run smooth as can be with the choke in. My wife's Cub Cadet tractor is the same. If you leave it sit for a month or two (typical because it rarely makes it through 2 to 3 mowing's without being pulled back into the barn with my tractor) it will only start on full choke, run on partial choke and hunts like crazy. Mix in some fresh gas or drain the tank and it will run as it should... Now both of these problem children will run great even on aged non-ethanol fuel, this however is getting harder to find in my area. If your tank is fresh, I'd pull the carb again or try a little cleaner like sea foam in the tank and leave it run (no load) for a little while with the choke on so it doesn't hunt and see if it clears up.

Cali fuel left in for about 4 months.

 

[barefootin]

I'd start there... Disconnect the line at the shut off and drain some into an old mason jar or clear drinking glass (not to be reused)... I bet what is on the bottom of your tank looks like water and barely smells like gas anymore. If so, the ethanol separated... It may take a little while for the fresh gas to make it through the carb unless you cut the fuel, drain the carb bowl, and connect your aux tank or the refill the onboard tank. Let us know how you make out...

 

[Keith_J]

Running lean at part throttle, enrichment at wide open throttle alleviates the lean. Bad gasoline and carb issues.

 

[rustystud]

Running lean at part throttle, enrichment at wide open throttle alleviates the lean. Bad gasoline and carb issues.

The fuel your running is part "Ethanol" , which will leave all sorts of nasty crap in your carb. The best thing to do is completely rebuild the carb, and start to use on a regular basis a good fuel additive like "Pri-G" , or any "Marine grade" fuel additive. I sometimes forget to add the additives to all my equipment out here and I can get this horrible nasty crap in the carburetors. It will also start to eat the aluminium on the carb.

 

[zarathustra]

I would approach it from the standpoint of it being an engine / carb problem and not on the generator end. I had a Troy Built roto tiller that, over time, started "hunting" at idle. Applying the choke reduced the problem, but it just wouldn't run right at idle. I took the unit to the shop and they did a complete carb kit. Problem solved!

So, I'd imagine that the carb is gunked up and needs to spend some quality time in the sonic cleaner.

Assuming that you've made absolutely sure that the fuel is OK and without water in it, and the plugs are OK and there are no leaks, the carb kinda falls out to be the most likely culprit