Honda GX200 Issue

[Starke27]

Hi all. New to the forum. I searched around several forums and have tried to narrow down the problem and I’m stumped.
My father in law gave me two power washers that he could not get running properly. Both have the GX200 engine. One runs great but the pump is shot. The other the pump is good but the engine won’t stay running. So I am going to put the good engine and pump together and sell it to fund a go kart build with the other engine assuming I can figure it out. The throttle keeps moving back and forth constantly revving. I cannot take the choke off more than half way without it dying. I thought it was starving for gas. I have tried a lot of troubleshooting:

new carb, coil, spark plug, fuel filter, and low oil sensor. Oil change and fresh gas.

also loosed the gas cap to see if the vent was not working anymore.
I am out of ideas. Any help is appreciated.

 

[BrownStainRacing]

Hi all. New to the forum. I searched around several forums and have tried to narrow down the problem and I’m stumped.
My father in law gave me two power washers that he could not get running properly. Both have the GX200 engine. One runs great but the pump is shot. The other the pump is good but the engine won’t stay running. So I am going to put the good engine and pump together and sell it to fund a go kart build with the other engine assuming I can figure it out. The throttle keeps moving back and forth constantly revving. I cannot take the choke off more than half way without it dying. I thought it was starving for gas. I have tried a lot of troubleshooting:

new carb, coil, spark plug, fuel filter, and low oil sensor. Oil change and fresh gas.

also loosed the gas cap to see if the vent was not working anymore.
I am out of ideas. Any help is appreciated.

Sounds like it's losing fuel signal and slinging open to draw in more fuel from the high side to keep it running. Then closing again because to much rpm.
Surging or hunting

Pull the carb back off and inspect the black insulator plate and check for very small cracks. I see this alot on engines for utility uses. They are usally fine until taking off and tightened back up.

Make sure those gaskets are good and installed correctly. Those gaskets are cheap and shouldn't be reused.

Checking and adjusting valves never hurt anything.

You can adjust the governor, but honda's are dead nuts on, and only need adjusted when some dummy played with it.

 

[Karttekk]

Unscrew the idle screw then remove the pilot jet under where the idle screw is. It's black with one or two o-rings. Spray some carb cleaner through the small hole going through the center of the jet along with a fine wire. If the pilot jet is restricted, the engine will surge.

 

[Starke27]

Update. Cleaned out the jet. Checked the black insulator. Looked good but when I got it off I noticed the gaskets were not correct. Ordered a gasket set and replaced them. Now it fires right up on full choke but immediately dies. Going to have to check if I put something back wrong or what happened. Double checked that the oil was good and I know it’s got a new low oil detector on it.

 

[Denny]

Now disconnect the low oil sensor and never hook it back up again!

 

[Karttekk]

Here's a "gasket sequence" video