Well I installed a new opti the other day, the new opti cam with new Orings already on it. The old opti came out without any O rings on it! It is possible that some time in the past my mechanic may not have replaced the O rings when rebuilding the engine. Any idea what kind of effects this could have had on the car? I know it was the source of a small mystery oil leak, but could anything have gotten back into the engine?

Also, people recommended I get new waterpump O rings - I didnt use these at all! I didn't see anythign anywhere which should use them... Anyone able to help me out on where they were supposed to be used?

 

Likely your old opti o-rings had disintegrated. They seem to be used for stabilizing the shaft and are not used for oil control.

The water pump o-rings fit right where the splines stop on each shaft. They keep dirt out of the coupler.