Still ooo but thanks for the flank gap definition. Don’t know that yet. Is there a spec? I’ll see if i can find it in the manual on my flight home. Here are some more pics i pulled. 4 sides of same piston prior to any cleaning. Don’t know if the skirt scratches are cosmetic or have depth. Don’t remember any marks on the bore. Don’t know why this engine was pulled but maybe burning lot of oil?
Also, i think JOHN76 is right; these are likely Mahle pistons: the M w/ the numbers top and bottom Mahle describes that mark as their quality symbol - likely time of build or lot number, and alas they don’t look anything like VISIONAUT’s 9.5:1
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