I just got the new rear main seal from BMW with the carrier and all, and it looks exactly how I mounted the corteco seal in my old carrier - flush with the outside of the casting that you see when it's mounted on the engine. So, I don't think I have a seal alignment problem. Maybe it got folded over or kinked when I slid it on the shaft.

I hope to tear back into it tomorrow, but I have a question - can anyone think of a way to start the engine without reinstalling the transmission?

The problem is the starter motor bolts to the bellhousing on the transmission. If I could secure the starter somehow in the proper location, I could install the flywheel and jump the clutch safety switch to test the engine for leaks without the transmission installed. Otherwise, I'm in for a lot of R&R to trial and error this thing until I figure this out.

I don't know how different it will be due to your MT, but for my 2001 3.0i AT, here's a pic I took of that area, in case it helps you or someone else figure out how to rig something up.

Attachment 77167

In this photo, to help you get your bearings when looking to see what's what,
it was taken from above, in the engine bay, looking down at the starter
the blue and white masking tape are where the cylinder head (M54, inline 6) used to be
starter is the black cylinder at the bottom of the photo, in the middle
the starter solenoid is the gray cylinder to its right

Securing starter, without trans is difficult to do. I threw away a bad auto trans a year ago, and have regretted not trying to remove or cut the bell-housing off of it, for this purpose.

Any chance you can reinforce the thin metal shim that fits between block and trans and secure it to that? I looked on the E46 forum for ideas, but came up short.

Yeah, I think the bellhousing section is the only safe way to do it. I don't think you could reinforce that thin sheet metal plate and still have the starter align properly. Just too much risk in taking off a flywheel tooth or worse. Off I go to craigslist and offerup to see if anyone's got a junk tranny for sale.

You should be able to easily make up a mount plate from 6mm alloy - it only needs the mount points for the starter and a couple of bell-housing bolts. Since all the force is laterally through the plate, a 200mm sq. piece of alloy will be plenty strong enough (for a few starts anyway).

Good idea, IIRC the mounting surface is flat, and I think I have some aluminum flat stock lying around. If it's simple drill & go, that would be a good solution. It may have to be in an arc, though, following the curve of the bellhousing since the starter nose protrudes into the bellhousing.

That might work with a piece of (6mm or 1/4") alum plate. Use part of the thin metal shim as template to mark 4 holes (2 to hold starter and 2 to bolt to Block/head) and a cutout for the starter.

Maybe you figure out a way to secure the pin hole in the starter, but that is likely overkill in this application.

Exactly - just use the bell housing as a template and copy just the section that is needed to support the starter. :thumbup:

Well, we have a winner! Man, I would have bet considerable $$$ that I was leaking engine oil, but, yes, it is coming from the trans. I dropped the trans and saw a puddle in there while the back of the flywheel looked bone dry. I removed the clutch/flywheel anyway and confirmed. Once I pulled the throwout bearing guide tube, the culprit was evident.

Anyway, I think I fell victim to the (lack of) BMW special tool. Sometimes special tools are used to make the job go quicker for the tech while other times they are there to achieve a specific result. In this case, TIS said 'drive the seal home', which usually means tap it in until seated. BUT, that's using the special tool that puts the seal flush to the housing (like the RMS). Also, there's a sleeve tool that goes over the splines on the input shaft so you don't nick the seal. I was being very careful not to slide the new seal across the splines, but that's another area I may have screwed this one up.

Anyway, happy the cause of my leak is evident.

Wow - Mystery solved..Thanks for following up. I think when I installed my input shaft seal I used a piece of paper loosely wrapped around the splines (like a paper funnel) to protect the inside of seal. I think I gingerly tapped it in with wood dowels.

Good to know RMS seal was successful.