I assume with the new piston, that it ain't carbon build-up...
I don't think the cam chain could stretch that much without breaking...
(can't think it through right now,.. but, would a slack c-chain advance or retard?)...
May sound insane,.. but, try some Marvel's Mystery oil, (cap full, maybe two, in the tank... I cured a heck of a racket in a Datsun with that... (did you do valves when you changed piston?)...
.. if that don't do it,.. I think you're goin' back in to check the rings n' bearings...
PS,.. thanks for the 454 pulley tip,.. I'm workin' on it...
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PSS...
verslagen1 wrote on 04/18/12 at 23:12:40:How about a different cause... loose nut on the drive pulley?
WOW!... Versy blew me away with that one!... but, yes... check that pulley... I've been fooled by that sucker...
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