Engine started fine, ran well, but at end of mowing job, engine would
not cut back to idle. All linkages seemed OK, governor spring OK also.
Nothing sticky. Stopped engine by disconnecting plug. On several
restarts, engine went to high speed, no throttle control at all. Was
concerned about runaway, so always disconnected plug promptly. Tried
adjusting low and high speed jets, had no effect. Did not examine
throttle plate. Choke plate operating normally.
I'd bet this isn't a common problem. Is there an easy way to test
the governor by moving the arm manually? As I say the spring seems
fine. Could there be a huge air leak somewhere? Never seen anything
like this before!
Please advise on where to begin. I do not have the engine here now
but would like to begin diagnosis as soon as I return to my camp.
Thanks very much for help!
Frank