Rear main replacement without removing oil pan?

[superburban]

My neigbor is restoring a M151, and I am his mechanical advisor. (He doesnt have much mechanical experience, so he bribed me to help with a 12-pack of Mountain Dew. Dont tell him that I would have done it for free!)
We have the engine and gearbox removed and separated. He has a new rear main seal, but no oil pan gasket. I was wondering if anyone has replaced their rear main without removing the pan? Do you have to loosen the main bearing caps to change the rear main seal?

 

[nattieleather]

No you do not have to remove the oil pan nor the bearing caps to remove the rear manin seal. A few years ago I use to have a neighbor who worked on the same motor in towmotors (fork lifts) and when I had a leak in mine he replaced it for me this way. He took a small punch and centered it on one side of the seal on the metal part. He then gave it a good solid wack with a hammer. This cocked the seal where he could take a screwdriver and pop it right out. Then he tapped the new seal gently back into place. I think he coated it with oil first before sealing it, but its been 11 years so I don't remember the deatails. Just about the same proceedure as replacing a wheel bearing seal.
Joe

 

[superburban]

That is what I was thinking I was going to do, but it's better to ask those with more experience than I before starting. Thanks for the help!