Small Engine Troubleshooting Problems? Ask a Mechanic Now.
Valve is bent form hitting piston, valve likley stuck and hit piston!
So you say valve seat is loose? Seat may be loose in the head, Can't tell without removing the valve.
Good luck with it, you know more than I. I will opt out. Maybe I need more experience!
Hi, I would consider checking the valve guides, if you can see light and the valve is straight, then it seems the valve seat may of turned oval.