Sounds like it will need a rebuild if the piston is scored. Does not necessarily need straight fuel to score the piston, it it has been running lean or getting hot it can cause that as well.
A reminder why it's bad to turn off the fuel tap to stop the motor or to let it stall from running out of fuel.
Ahh, if only victa had kept producing the thumblatch catcher series, they would be in better shape today!
