[Charlie Fort Payne]

X570 with Kawasaki FS730V engine. Rather suddenly full throttle produced about 2/3 of full rpm, even without load. When throttle turned all the way down the engine dies. With just a little throttle the engine runs at idle smoothly and starts easily. Since the problem affects both idle and full throttle it seemed unlikely to be air filter, fuel filter, or spark plugs. However, because it was easy I changed these items. It did not change the symptoms. After the fuel filter change it ran for about 30 minutes and I it appeared that there was no fuel in the fuel filter. This is quite a mystery to me. The carburetor bowl couldn't possibly hold that much fuel. Any help would be greatly appreciated by this old man.

 

[tibadoe]

Did you check to see if the fuel line is clogged. Would not hurt to blow out fuel line back towards tank.

 

[Charlie Fort Payne]

I have not checked the fuel line between the fuel filter and the tank. I will blow air backward from the fuel filter to the gas tank first thing in the morning. Many thanks, Charlie

 

[dixie460]

So high throttle produces 2/3 RPM and low throttle cuts the engine off. Your throttle butterfly is not following the throttle command. Do you have a mechanical throttle cable? If so, adjust it.

If electronic throttle (no mechanical linkage between throttle lever and engine) then you'll need a tech manual or at least the specs for whatever senses commanded throttle and whatever actually positions the throttle butterfly.

Ignore the fuel filter for now, it's getting fuel if it ran for 30 minutes lol.

 

[Charlie Fort Payne]

I returned to the problem with the assistance of the midday sun and my one good eye. Upon review it was apparent that the linkage between the governor and carburetor throttle had dislodged. I put it back in place and went back to work. Thanks, guys.

 

[tibadoe]

Glad you got that resolved.