There is a knock, tap, coming from engine. I've ruled out lifters. But I can't figure where noise is coming from. Goes away sometimes when engine is warm
If the tap quietens down when engine warms up,it will be a weak lifter.
That's what I first assumed. it used to stop when engine warmed up, now it's continuous, but does get quitter. I put marvel mystery oil in it. I have had luck in the past with that freeing up lifters. Do you think it could be piston knock?
did you inspeck the rocker arm/s
That was my next step. Just trying to get other opinions. Thanks
A piston knock would not go away,leaning more to weak lifter.
How did you rule out the lifters?
It just has a deeper sound than a lifter. I may be wrong
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