Somebody edumacate me on a lower timing cover leak
 

1994 c280. Had headgasket replaced. Worked fine.

A couple of weeks later, a new leak appeared. It seems to be the lower timing cover seal...so I'm told. He tells me the labor is almost as involved as the headgasket repair in the first place.

I searched several times and I'm not finding any info. It seems to be leaking at the bottom and then being blown/flung around by the flywheel/harmonic balancer or whatever that is.

Any info is appreciated.

Thanks.

if it's the front crank seal, no way is it as involved a job as the head gskt. pull the radiator, remove the belt, fan and shroud, (fun part now) and remove the lower pulley. big socket, lotsa torque on it, have to lock the flywheel or use an impact along with a big air tank. seal's behind the pulley. good luck, chuck.

Thanks. Let me ask you a couple of questions.

1. Is this something that should have been replaced when the headgasket was replaced as a matter of definite course? Or...just replace the upper?

2. He says it it is leaking at the top. I think that there is a decent chance, after reading about how to get the bottom end of the top cover sealed, that either he didn't get the upper sealed correctly or that the work he did actually disturbed the lower and caused the leak.

It didn't leak immediately after the headgasket, maybe 4-5 days and couple hundred miles.

Thanks

It is very easy to roll the U shaped seal when reinstalling the upper chain cover. A rolled seal will leak. The lower timing chain cover does not need to be removed when replacing a headgasket, so it is very unlikely that the front crankshaft seal was affected.

J. M. van Swaay

Sounds like the end of the upper where it meets the lower may have rolled or not sealed. I bet it ends up being that one, and not the lower, as you suggest.

Thanks

You can usually see a rolled u seal by careful inspection with a mechanics mirror. (one of those small mirrors on the end of a telescoping stick) Look closely at the bead of the seal that is visible between the upper and lower cover. If the amount of bead reveal changes or appears to twist, the seal is probably not properly seated. (ask me how I know.............)

J. M. van Swaay

By the way, because of the tilt of the mating surface between the top and bottom half of the timing cover, oil leaking from this area will usually show up on top and around the chain tensioner.

J. M. van Swaay