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Registered
Join Date: Oct 2004
Location: Gainesville GA
Posts: 114
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Cylinder wall damage at top, in ring area
All,
While inspecting a newly rebuilt engine for purchase I discovered, using a Snap-On BK5600-OD bore scope, what appears to be a chipped damaged area in the very top section of a cylinder. The damage appears to be just below the top ring area of the piston at TDC and just above the top of the oil ring. The bottom of the photos, the silver area, is the squish band area of the cylinder head near the intake valve. Based on the photos below can anyone tell me how much of a risk do I have that the cylinder or piston rings will prematurely fail? The engine has not been run, does not even been filled with oil but is fully assembled and ready to be installed into the car. Just hoping to receive some wise counsel from the engine experts on Pelican. I also posted this in the Engine Rebuilding Forum but thought the TURBO guys my have some unique insight on this situation considering the combustion temps and thermal expansions they experience in their engines.     
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10-12-2019, 07:58 AM
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Its hard to tell, but are you sure its actually damage in the surface of the cylinder wall and not simply a piece of debris that is stuck there?
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10-12-2019, 10:38 AM
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If it is indeed damage to the cylinder wall in a location where one of the rings passes over it
I would be concerned Tony |
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10-12-2019, 03:57 PM
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Slantnose from HELL
Join Date: Dec 2004
Posts: 888
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Nikasil is HARD!!!!! to say the least. It looks like something sharp fell right in and on the cylinder wall. It definitely happened during the build. The damage is too bright to have been done prior. Pull that bank apart and just that head to pull the sleeve and have it replated. The general rule is anything less than .004 will be OK. Unfortunately that looks more than .004
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It changes from time to time..... Last edited by GJF; 10-12-2019 at 05:09 PM.. |
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10-12-2019, 05:06 PM
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