Rear Crankshaft seal replacment question

[alpina]

Hi All,

I hope you can give me some advice.  While having my car serviced I asked the garage to investigate a minor oil leak. I suspected it was the rear crank shaft seal.
this has now been confirmed by the garage. the car is running well, only has this minor leak. from reading the forums, I understand that replacing the bottom half of the seal
can often cure the problem. this is what I suggested to the garage. However the chap at the garage has said he can replace the whole seal without removing the engine.
I could not quite understand how he would be able to achieve this. from what I understand he would remove the transmission, and somehow lower the crankshaft enough to
replace the seal. I don't fully understand. I have found no one on here, or anywhere that has done this. He seam very confident that he can do it. But I and slightly worried.
We are waiting for the seal to arrive from MB. so nothing has been done yet.
So what should I do?  get him to replace the bottom half of the seal only no disturbing anything, or let him go ahead with his method to replace the whole seal.
I would really welcome your thoughts. So I can make an informed decision. (and get some sleep)

thanks
DM

[Jonny B]

The search function is your friend. I just tried "rear seal crankshaft" with the search set to "match all words" I got just a single page of hits. You should be able to find what you need in there. Good luck.

[Benz Dr.]

It can't be done regardless of what he says. And, you have to remove the oil pan to get the bottom seal in. To remove the oil pan you pretty much need to remove the engine so it will clear the sub frame so what appears to be a small job, isn't at all.

I would let it leak unless it becomes like the Exxon Valdees.

[ja17]

Yes, it can't be done. Inform the chap that the seal is pinned in place. Other manufacturers do not pin the seals.