Shindaiwa 488 Rebuild Woes

[David Young]

is there any chance that the throttle plate is hanging up?
if you shut it off and restart does it reset?
could be the linkage could be the plate itself is loose and moving around.

 

[beaglebriar]

Done it a few times, plugging muffler and intake, and testing thru the impulse line. It's held pressure and vac just fine, which is stumping me. I wondered if maybe the crank seals are on their way out, and losing pressure once there's some friction added...?

I'm converting it to a 488P, and have all the parts needed except the black plastic elbow after the carb.

Are you rollover it over while testing? Have you dunked it in a bucket of water while under pressure??

 

[eric4]

Are you rollover it over while testing? Have you dunked it in a bucket of water while under pressure??

Honestly, I hadn't considered doing either. Assuming rollover means turning the flywheel while under pressure?

 

[whybother]

Honestly, I hadn't considered doing either. Assuming rollover means turning the flywheel while under pressure?

Yes, turn the crankshaft while you are pressure/vacuum testing it. Sometimes the seals show no signs of leaking when the crank isn't turning.