[Dave Ray]

rvanburen, yu might want to climb under and take a closer look at the seal itself, mainly, the rubber sealing area itself.

A couple of years ago, I got a free, recently completely rebuilt GMC 305 V6 "big block" engine, running, but, had a front cover leak. After investigating, I fund the seal to not have any of the rubber seal left in the seal metal housing. After pulling the front hub off the crank, I discovered the hub seal area had a groove of metal bent upwards, at the locating groove area. Looking into the crank snout are in the front cover, I saw the reason. the crank key was sticking up out of the rear of the groove, and, when the hub was installed, the metal of the hub curved and lifted. then, when the engine was started, the curved metal literally machined the rubber seal material right out of the seal metal as the engine ran.

I installed a new seal, and set the crank key back into the crank groove as it should have been in the first place. I then made a muffler tubing steel seal race, pressed it onto the hub to repair the groove, sealed it, machined it to the right dimension, and, the whole mess doesn't leak now.

Take a look, might have happened to you as well.