curious cam sprocket wear- 340

Neal Zimmerman said

I agree with rusty, if the cam key was cocked up in the back that could explain the cam gear being "forward" and shoving the eccentric into timing case, but it doesnt explain how the front of the thrust plate and cam sprocket did their bump and grind as seen in photos.
neal

Click to expand...

I can very easily see the cam moving back and forth, and when it moved back, it could hit the thrust plate with some vigor. The forward pressure of the oil pump resistance and the lifters on the lobes is fighting the chain tension as it tends to keep the sprockets aligned evenly, and the cam is going to move back and forth as long as there is any slop in the clearance.

I would reassemble with the intermediate shaft out as suggested and check all the end plays.