There are those who suggest driving *very* strongly for the first 20 miles to ensure the piston rings bed in properly before the honing pattern wears off. A quick google returns things like this:
The honing pattern is still clearly visible on my 150,000 mile car.
Daves suggestions don't clash with my idea of running in. My wife was too gentle with a MM engine I'd reconditioned. After 5000 miles it was still burning oil. An italian tune didn't solve the problem, but rehoning the bores with a harder run in did. Mike.
Are you saying that the honing pattern hasn't worn off as it should? Has the honing pattern became permanently glazed, is the pattern too severe or are your piston rings not touching the cylinder walls?
Zathras (Zathras ) gurgled happily, sounding much like they were saying:
No, the bores just haven't worn to any appreciable extent.
If the rings weren't touching the walls, it'd be VERY noticable. Not least because it'd refuse to run completely, since there'd be no compression whatsoever.
I had the head off my Saab a month or two ago - there was no noticable wear in the bores, despite somewhere north of 160k miles and some probably questionable maintenance history before I bought it.
Is that because the walls have glazed though? My understanding is that the honing pattern is not meant to be a permanent feature - otherwise what's it there for?
Maybe it is visible (like a watermark) but now has no effect on the rings ?
& it should have worn down to less than the thickness of the oil film.
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