1994 Camry 4 cyl. oil pump will not turn

Changing the timing belt, replacing oil pump O ring and cover gasket.

Oil pump sprocket turns fine, until I tighten the cover bolts and then it will not budge.

In the middle of the job and I'm stuck.

Any suggestions greatly appreciated.

First I used Lucas oil treatment as assembly lube, and thinking it was too viscous, wiped it all off and used 10W30 Mobil 1. No change.

Lined up the marks on the gears, no change.

Everything is fine until I begin to tighten the cover bolts - and they're just beginning to tighten, it is as if the oil pump seizes. Not even sure how it could bind. Everything looks normal.

Changing the timing belt, replacing oil pump O ring and cover gasket.

...

Everything is fine until I begin to tighten the cover bolts - and they're just beginning to tighten, it is as if the oil pump seizes. Not even sure how it could bind. Everything looks normal.

PROBLEM SOLVED!!!

Took it apart and put together at least 3-4 times, same result - jammed sprocket.

Asked for divine guidance, and decided to just go ahead and fully tighten the cover, then try to force it to turn with a band wrench, but as I was tightening the upper right bolt, the cover shifted position slightly, and now the sprocket turns more freely than ever -- perfect.

So all is well and can continue with the work. No idea what was off, the cover edges looked all good, but something was slightly misaligned enough to bind severely.