nm9stheham
Well-Known Member
Scored as in lotsa grooves? My (fortunately) limited experience with too tight a piston-to-bore clearance showed localized dark spots on the piston skirts where the pistons badly scuffed or momentarily seized (the engine just gave an abnormal jerk) , and overheated the piston material in spots. The skirt diameter shrunk due to the localized overheating.
So check the diameters at the skirt in particular, to see if they are normal or not. And the bore diameter to see where the clearance is at as disassembled. Some minor scoring seems to always happen (for me). Maybe yours were just on the margin of scuffing...and it may be lack of oiling or excess chamber heat, not clearances.
Any pix? Head plates used while boring/honing?
So check the diameters at the skirt in particular, to see if they are normal or not. And the bore diameter to see where the clearance is at as disassembled. Some minor scoring seems to always happen (for me). Maybe yours were just on the margin of scuffing...and it may be lack of oiling or excess chamber heat, not clearances.
Any pix? Head plates used while boring/honing?















