Complexity of replacing the front crank seal.

[ozymand]

Hello folks!

So I've been dealing with a recurring issue with my '91 318is since I've bought it. At first I thought I had an issue with the oil pan leaking (bad gasket) but that turns out was a bad analysis. After further inspection, it appears that I'm losing oil out of the front crank seal.

I have been reading this (linked here) thread that has quite a few pics and a description of replacing the front crank seal. My only concern is, I realized he dropped the front cross-member (another part of his repair) and did a few other things in the process.

So how far do I need to go into the engine to replace the front crank seal? Do I have to drop the lower and upper oil pan? Do I need to remove the cross-member?

As a follow-up, if it's too hassle-some (as if I need to drop the cross-member and thus mean supporting the engine via an external brace), anybody in PDX know of a reliable shop that'll do the work for a reasonable rate?

[KenC]

You don't even have to remove the lower timing cover.  I've done it with a lift in 30 minutes total.  Most of the time is taking all of the belts off.

http://www.autobahnsport.com/ - Give those guys a call.

[ozymand]

Thanks Ken. Is it doable on stands? Don't have access to a lift. Got a quick overview of what I need to remove/do to get this done in my garage?

I'm swinging by their shop tomorrow as I was going to see if they might have some bits and pieces I need to put the car together (missing clips, fasteners for various trim pieces, etc).

[doitover]

I just did this and being a novice at car repair this is my input.

It is easy, the hardest part is removing the crank bolt. The next somewhat difficult part is removing the old seal due to the space limitation. Just be patient.

The write up you refer to I think shows using a wire wheel to remove the gunk left from the old seal. I was able to clean it up with brake cleaner and there wasn't a groove that I could detect. It isn't leaking yet.

Be certain the hub is back on the key before you crank bolt back in. I'm probably the only person to have ever crushed the thing. I can tell you it's a major job to replace it.

One other thing, if you have never replaced a seal before, you need to be careful that you press the new one in with even pressure around the circumference. Most people do that by using a socket that matches the diameter of the seal and gently pounding it home.

You may find when you pull the hub off that the leak isn't coming from the crank seal. Mine was actually coming from either the timing cover or the cam cover, or both. I changed the seal anyway since I had it.

[KenC]

Easily doable on stands.  It can be a pain to remove the fan/shroud without the correct set of wrenches.  Crank bolt is easy with a breaker bar.  Just have the car on the ground in 5th gear to keep it from spinning.  Remove the old seal with a screwdriver.

While you're working down there, replace the oil filter housing gasket and O-ring.  that's where mine was leaking from when I thought it was the crank seal.

[Isamemon]

thats where one of my ( many) leaks is too

[ozymand]

Thanks for all the help, and I feel more confident about completing this repair now. Now comes the fun part about finding and buying all the parts I need. :cool:

[KenC]

Go to Discount Import Parts on 99E, should be less than $20 for front seal and oil filter housing gasket and O-Ring.

[ozymand]

When you said "o-ring", do you mean part 8 (linked here) in the drawing? Realoem is such a great resource.. hehe.. makes it a lot easier finding exactly what gasket/seal/o-ring I need to get.

[KenC]

yes, part 8.