Valves are improperly gapped. Gap the valves to .010. Let them rattle a bit.
Mine did this and I thought it had burned a valve or lost the rings.
Yes, the crankcase pressure powered fuel pump can be an issue if the tank is in the rear of the mower and not gravity fed.
*I put myself through college working in a garage in the 80's.
Mine did this and I thought it had burned a valve or lost the rings.
Yes, the crankcase pressure powered fuel pump can be an issue if the tank is in the rear of the mower and not gravity fed.
*I put myself through college working in a garage in the 80's.