What is the best method of removing the seal in the bell housing w/o hurting the Aluminum bell housing?
(yeah I know, ... Carefully)
But really? I don't want to bodge it.
Hi maseratiguy,
The method outlined in the shop manual (page 13-10) suggests that the seal can be pried out with a screwdriver, levered in the angled notch. This is assuming that the "centering ring" stays attached to the gearbox and not the bell housing when the two are separated. But in my experience, sometimes the steel centering ring gets stuck in the bell housing and that has to come out before the seal can be extracted.
Now I have tried to pry out the seal with a screwdriver as suggested in the shop manual, but have had very limited success. No matter what size of screwdriver I use, I can't get the angle low enough to get under the seal without the risk of digging into the aluminum of the housing.
You are right to be cautious about the aluminum counter bore that the seal resides in. You definitely don't want to harm that precious surface or you risk ongoing future leaks (even with a new seal).
The best way I have found of extracting the seal is by destroying it, albeit very carefully, by prying, little by little, all around the edges, with a sturdy-pointed 'pick' (or a very small screwdriver), until part of the seal's encased metal shim is raised enough to get a hold on with a pair of needle nosed pliers - and then pull. The key is to not worry too much about ruining the old seal - you're going to replace it anyway - you just don't want to scratch or mar the aluminum surrounding it.
The seal itself is a rubber-encased steel washer with a small steel spring behind the center sealing lip. You could try and leave the spring and center rubber lip intact, just to provide a little something extra to pull on later, but if you rip them off while you're trying to pry up the metal washer/shim in the base it's not a big problem. In fact removing the spring and lip can often expose the embedded metal washer so that you can see what you want to pry up to pull on with your pliers.
The trick is to place whatever you use as a prying tool under the encased metal washer of the seal but above the aluminum surface of the bell housing counter bore. There should be about 1mm of rubber under the metal plate of the seal, so you should try and shove your tool right under the metal encased in the seal, and use the opposite side of the bore to pry against. Never try to pry against the aluminum under the seal.
Little by little you should be able to slightly distort the metal portion of the seal enough to get a pair of needle nose pliers on it, then you can grab and pull.
In summary: locate the metal shim encased in the rubber of the seal, bend that metal portion (inside the rubber of the seal) until you can get needle-nose plier tips on it, and then pull.
Good luck and be careful.