Mower surges, governor seems to the issue

[updatelee]

Ok, so Im baffled. I have to run the mower half choked or it surges wide open throttle then idle, and repeats over and over. Reading up everyone says that the surging is a lean issue caused by a dirty carb. So I took the whole thing apart and cleaned it all out, used a pin to ensure the jet is 100% free of obstructions. It still surges. I changed the spark plug and air filter, still surges. Checked the flywheel key to make sure that it didnt break off and advance the timing. Its good. reassembled and still surging.

So now I thought what if I just bypass the governor and just hold it still so it cant surge? runs fine, I can run with no choke and adjust the speed manually, runs 100%. So I tried making the governor spring tighter, its pretty much impossible to get right, its either too tight and runs WAY WAY too fast, or too loose and pulses.

Its a hydro gov, not one of the fan style ones.

Is there any way to adjust these and resolve this issue?

 

[Rivets]

If you continue on the path you describe you are going to be in big trouble in a very short period of time. When you clean the carb did you take a close look at the float level and the float needle and seat? How did you set the float level?

 

[updatelee]

If you continue on the path you describe you are going to be in big trouble in a very short period of time. When you clean the carb did you take a close look at the float level and the float needle and seat? How did you set the float level?

Float itself seems fine, no fluid in it. Moves freely.

I cleaned the float needle, the rubber tip is nice and pointy no deformation. The fuel passage in I cleaned with carb cleaner as well and used a needle to ensure its free from obstructions. Im surprised how small it is, the needle barely fits, a 1/16" drill bit is much too big. The float seat is brass and appears fine.

I never set the float level, the entire carb seems like its not designed for any adjustments. There is no adjustments for the jet, lean/rich, or float level. The only adjustment is the idle speed.

 

[Rivets]

The tip of the needle may look good, but I always replace them. If you turn the carb upside down the float should be level with the carb body or slightly lower side opposite of the float pin.

 

[updatelee]

The tip of the needle may look good, but I always replace them. If you turn the carb upside down the float should be level with the carb body or slightly lower side opposite of the float pin.

When upside down the float is level maybe a little lower then the pivot pin like you say.

The thing that has me baffled is it runs fine with the gov linkage disconnected and controlling the throttle manually.

 

[Rivets]

If you feel that it is not a fuel problem, then you can get a tach and check to see if it is running at 3000 RPM's. If the engine is running too slow, it will also surge, but then you have to adjust the throttle control, not the governor. Playing with the governor without a tach is asking for trouble. Just my opinion.