Gas generator will only run with half choke??

[BoyntonStu]

It used to run with the choke completely off?

Is it OK to run it this way?

Is a repair necessary?

[willshak]

on 10/17/2007 3:22 PM BoyntonStu said the following:

Hard to say. Dirty air cleaner, carburetor adjustment, fuel filter, or something else. Any small motor repair place can diagnose the problem, even a lawn mower service.

[Meat Plow]

Nope

Yep

[Steve Kraus]

If it's running stably in that position you're not hurting anything. For some reason the mixture with the choke off is too lean and leaving it partly on corrects that. The engine is then getting what it needs.

It *should* be repaired but it's not like it's hurting itself if it's running smoothly.

Of the possible causes previously given it won't be a dirty air cleaner as that would have the same effect as the choke, richening the mixture. Fuel filter....maybe but I wouldn't bet money on it. Carb adjustment...well that doesn't change by itself but readjusting it could fix things. (Back off the main carb adjustment screw maybe a turn and see if it then runs sans choke.)

I would guess the problem is caused by dirt in the carb's fuel passages. Repair would require disassembly with some tiny parts to deal with and you still might never find anything specific but a general cleaning and reassembly might correct that. But that might not be something you want to get into. For now I would just try readjusting.

[Robert Barr]

Carb adjustment...well

If it's a halfway recent engine, it won't even have any mixture adjustments. Some of these consumer grade engines won't run right, brand new. However, the OP said it used to run OK, which means the carb probably needs a thorough cleanout.

[Meat Plow]

If the OP is going to rely on his or her generator then, NOPE it is not ok to run it "this way" and YEP it needs repaired before it doesn't run at all.

[PaPaPeng]

I had a gas powered weed eater with the same problem. After many (self done) failed fixes the final problem was found to be a factory assembly problem where the cylinder head was not tightly secured to the crankcase. This allowed air to get in during the crankcase suction cycle and therefore degraded the carb suction. A half choke permitted enough suction for the engine to operate. Of course it became worse with time. Just something simple you can check on. Make sure all the screws are tight. Do not over torque.

Of course, if you can, clean the carb, the fuel line and the fuel filter. In an earlier case of a cranky lawn mower the problem was traced to "dissolved" grass scraps forming a slimy cellulose fiber film over the fuel filter screen. The cellulose film was barely noticeable on casual inspection. The grass scraps got into the fuel tank when refeulling and my not taking care to clean the funnel throughly before pouring.

[Stormin Mormon (on backup com]

Probably the gasket between the carb and the side of the engine is missing or damaged. It could be sucking in unfiltered air, which might contain dust and dirt. That could damage the cylinder.

I'd try to get it fixed.