04-03-2023, 02:17 PM
This is perfectly normally noise on an engine that has backlash in the timing gears.
As the cam rotates, the followers (aided by the valve spring), push down on the camshaft and takes (snaps) up the slack. This manifests in the clunk you hear in your film, the cam gear is slamming against the crankshaft gear. If you hold the camshaft gear with your hand as you rotate the noise will be reduced, adding thick oil will have the same outcome.
As the cam rotates, the followers (aided by the valve spring), push down on the camshaft and takes (snaps) up the slack. This manifests in the clunk you hear in your film, the cam gear is slamming against the crankshaft gear. If you hold the camshaft gear with your hand as you rotate the noise will be reduced, adding thick oil will have the same outcome.