OK, so this is my car we're talking about here.

We checked the distance between the front of the crankshaft sprocket and the water pump pulley flange, and the pump flange is farther back than the edge of the crankshaft sprocket by a significant amount. This would definitely account for the wear. By the way, the pump is a reman Laso unit (mfg. date on the pump is '05).

Does anyone have a 968 apart to check this measurement on? I don't have time to pull my other 968 apart right now.

Thanks.

 

Just to give everyone an update on this, if they ever run into this in the future.
The problem was the crank pulley was too far forward. That was because the crank was walking forward in the block. We were able to shift the crank back far enough to line everything up to verify the theory.
That the crank moved like that tells us the thrust bearing is worn past spec.
Next step, engine rebuild!

 

D'oh!

I was following this thread; I haven't had my S2 motor apart yet...glad to see you guys got this squared away.

PS - glad to see yet another PDX 944/951/968 owner!