Honda GX270 Surging. Go For It Click and Clacks.

[BrotherBart]

My first DIY question.

My big generator is powered by a genuine Honda GX270. Unlike my five Chonda clones it is my only pain in the butt. What is happening this time:

The engine surges unless on half choke. Not so fast... New fuel and I put a new carb on it and it still does it. Carb is adjustable and has been set as the Honda manual dictates. New carb, new plug, new tank shut off valve and all new fuels lines. I can put a finger on the governor linkage and it stops surging. I can put it on half choke and it stops doing it.

Next?

 

[velvetfoot]

Fuel filter?

 

[gzecc]

Is the spring on the governor correctly?

 

[fbelec]

i have a crapsman mower that was doing that and it turned out to be that it was sucking extra air from the start/primer button replaced 3 carbs with no adjusters for air fuel and it was the primer all the time.

 

[btuser]

i have a crapsman mower that was doing that and it turned out to be that it was sucking extra air from the start/primer button replaced 3 carbs with no adjusters for air fuel and it was the primer all the time.

Found the same thing once. Ethanol is a PITA.

 

[BrotherBart]

Eliminated the fuel filter when replacing hose to see if that was it. Nope. No primer bulb and replaced all gaskets. Nope.

Spring is a possibility. It is installed correctly. May be weak.

 

[velvetfoot]

air filter?
Can't be the air filter, it probably gets little use, though could be some rodent-related thing?

 

[BrotherBart]

New air filter and does the same thing with it on or off.

Tis a mystery.

 

[fbelec]

same crapsman mower had a head gasket prob which also did the hunting

 

[bioman]

sounds like you got some watered down gas, it happens. get you some HEET at the auto store or wally world & put the hole jug in there. see if that don't help. get the yellow bottle of heet. hope this helps

 

[BrotherBart]

Yeah this thing is driving me nuts. Fresh gas and I filled one of the Chusky generators and the Chusky engine on the splitter from the same can and they rock with it. I just figured at first that I had left gas in it and gunked up the carb, again. Now everything is new from the tank valve, drained the tank before I started, to the carb and air cleaner.

Worst case I just run it with a little choke. The pig sucks gas like crazy anyway. The reason I have the smaller ones around. Irritating because then it doesn't wind quite as high which makes voltage output dicey.

 

[BrotherBart]

Starting to think it has to be an air leak. I will be pulling out the water spray bottle and investigate. Of course with one lung air cooled engine I will be drenched.

 

[JustWood]

Had the exact same problem with my 20 HP Kohler a month ago. Fresh gas, same thing.
New plug . BINGO!

 

[MasterMech]

Try holding the throttle closed, forcing it to idle. Does it run ok? You can hold it at 3600 rpm or so no prob? How rapid is the surging? Any chance this unit has an "auto idle" feature?

 

[BrotherBart]

I tuned it at idle per Honda manual instructions. Don't have a tach for it but idle is smooth. Only when I raise the rev to genny ouput level. It isn't an up and down surge. Three to one smooth to surge I would say. No auto idle. It is a pretty bare bones GX.

Why I love things with four to eight cylinders or turbine engines. Know how to make'em hum. One lung'ers make me crazy. I would just give the thing away but six thousand watts is handy on occasion. My two smaller ones total it but this one can kick it down one wire.

I think most of the bases will be covered when I soak connection points with carb cleaner looking for an air leak. Works on the big'uns.

 

[Bret Hart]

Try running it with the fuel cap off or just partially open. Be careful the gas doesn't splash out though.

 

[charly]

Try a new plug... Is there a fuel filter inside the tank as part of the shut off valve?

 

[BrotherBart]

Thanks. Brand new plug. Cap off. And fuel filter removed. No filter in the brand new shut off valve and fuel line. I am thinking of scheduling an Exorcism.

 

[BrotherBart]

Thanks for the ideas folks. If I get it figured out I will report back.