What is this vertical scratch?

mk3ukr

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Pulled my cylinder head few days ago, found this vertical scratch on cylinder wall. It is marked with arrow on attached picture. My guess it caused by too tight piston ring gap.



Can anybody confirm it?
Thanks
 

jdub

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Or, a piece of hard debris caught in the ring lands. Could be a piece of the ring as well.
You're not going to know until you pull the piston.
 

mk3ukr

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jdub;1316853 said:
Or, a piece of hard debris caught in the ring lands. Could be a piece of the ring as well.
You're not going to know until you pull the piston.

I will see it later, can't disassemble shortblock now, left my engine in car for fabrication of exhaust manifold
On other cylinder I have similar few parallel vertical scratches, though less pronounced. Can be due to rings turning in grooves and leaving multiple scratch marks?
 

Supracentral

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99 times out of 100 it's physical debris. Was the car ever run without an air filter? You'd be amazed how adept sand is at getting stuck in rings.
 

mk3ukr

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IJ.;1316963 said:
Did you deburr the edge/corner of the rings when fitting?

Not sure, motor was rebuilt not by me. Rings are JE, machinist had to file them to get to specified butt clearance. Possibly he did not removed sharp corner.
This time will do everything by myself