So some one comes in with an engine that won't start and you find a hole in the piston
He says it won't even start on starter fluid
So do you attribute the hole to the use of starting fluid or do you think the hole was the reason it would not start in the first place and diagnose preignition from overheating ?
You don't stand there with 2 cans of starting fluid madly squirting it down the carb till the engine hydro locks but other people do
In 11 years I have had 2 engines with holed pistons
Immediate assumption
plug causing pre-igniton
Repair
Replaced piston & rings , honed bore , replaced the timing key & magneto coil.
Engine is still running
Why did it fail, don't know & don't care unless it is a warranty problem .