Please,
if I am restoring an old engine and I see that one particular piston has axial score marks, what does that tell me. Do I suspect the big ends ? Any other suggestions ?
The marks are not too bad. It's just that the other pistons have none.
Thanks
Snark.
Is the bore ok? If so and the scores aren't too bad I wouldn't worry too much. Could be the results of minor seizures if that piston was a tad tight (quite common on two-strokes) in which case lightly relieve the area around the marks with a very fine file. More likely though, a bit of something nasty found its way into that pot so make sure that it is not still lurking when you reassemble. Tight or misaligned big or little ends can cause excessive side thrust on the piston, but that would show up as a wider area of wear (I've even seen melted portions!) rather than light scoring.
Nick H
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