Please help me diagnose an engine knock. I have about 8,000 miles on a good
build quality slightly "warmed" balanced engine. Recently I hear a knock on
start up that disappears alltogether when the engine is warm. I only hear the
knock when the engine is cold and idling at less than 1000 rpms. It may be
there when cold at rpms greater than 1000rpm's, but I can't hear it. The knock
is a "clack, clack, clack...bottom end noise. It sounds like what I recognise
as "piston slap". Maybe a wrist pin? I hear it best as the rpm's fall to 800
rpms or so. The engine runs like a champ. There is the usual puff of smoke
when started, but otherwise burns very little oil. Oil pressure is great.
Again, after the engine runs for one or two minutes, it is very quiet.
Waiting for Isabel
Joe Davis
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