I got this engine running finally after some much appreciated help from 30yeartech, but now it just lopes constantly while running unless the choke is left partly on (and running at full throttle). I've had the carb off about 6 or 7 times to clean it but to no avail. Today I bought an ultrasonic cleaner and disassembled and cleaned it again, but, just as before, it still lopes. Adjusting the lone adjustment screw changes nothing, no matter where it's set, either. Manually holding the governor arm still does eliminate the lope and the engine seems to run just fine. Anyone have any ideas???:confused:

On my FC150v there is an additional spring attached to the linkage to compensate for worn linkage(it takes up the slop), maybe yours has the same type spring but it is missing. Have a good one. Geo

Nope, that's not it. there's no wear in the linkage and all the springs are intact.

In addition to what Geo suggested, there may be a restriction in the pilot jet, or your governor may need to be adjusted.