Surging GX160

[chefwong]

OPE Gurus -

Another question. Just swapped a new carb on a GX160.
Gutting some pretty funky surge .

It's not fuel or dirty carb. Toyed with the idle screw which is NOT much...Pretty much straight Surging throughout. Thoughts - Suggestions ?

GX160 IDLE Surge

 

[Hokiefyd]

The surging is accompanied by governor shaft movement, right? In other words, the governor is causing the throttle to flip back and forth?

 

[tom slick]

I'd bet you've got a vacuum leak. Spray carb cleaner around all of the gasketed areas and see if something changes when the carb cleaner is sprayed.

 

[Clevy]

Originally Posted By: tom slick
I'd bet you've got a vacuum leak. Spray carb cleaner around all of the gasketed areas and see if something changes when the carb cleaner is sprayed.

+1. I make my living off those engines powering my air compressors. It's a gasket leak somewhere. Follow the suggestions above and you will track down the culprit

 

[bepperb]

On a non-adjustable carb that is clean my guess would also be a vacuum leak. Is the breather hose attached? You might consider new gaskets.

 

[Vikas]

At least on my Honda lawnmower, when I shut the gas petcock for the end of the season, the engine keeps on surging until it eventually dies due to lack of gas.