372xp , Odd piston wear?

[david newbie]

I pulled the cylinder on this as I discovered a torn intake boot, waiting on parts. The piston a nd cylinder are almost new, maybe 3 hours if run time. hasn't seen much time, cuz I was having trouble with what I was thinking was a carb issue, but turned out to be a crack in the intake boot, piston and cylinder look new, EXCEPT for this shiny spot on lower intake skirt. Has a new air filter

 

[Maintenance supervisor]

Everyone has told me that the tolerance is too loose for a piston that has that kind of wear.

 

[david newbie]

Everyone has told me that the tolerance is too loose for a piston that has that kind of wear.

That seems odd with a new oem cylinder kit

 

[Mad Professor]

That seems odd with a new oem cylinder kit

Check it quick using feeler gauges. Should be ~ 0.0025"

 

[bwalker]

That sort wear is caused by sucking dirt and crappy factory intake port chamfers.

That's alot of wear for 3 hours of run time.

 

[bwalker]

Check it quick using feeler gauges. Should be ~ 0.0025"

You won't get an accurate measurement doing that.
You need to use a micrometer on the piston and a bore gauge on the cylinder.