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If you change the rear main seal Bob, be sure to 'block the crank' which stops the crank from moving forward when the flywheel (clutch carrier) is removed.
The crank can be held in place by using a suitable length bolt in place of the rotor bolt. This bolt is screwed in x distance into the rotor bolt hole. The front engine cover is then put back in place. The deal is to screw the bolt into the rotor hole so that the front cover just touches the bolt head when the cover is replaced. This prevents the crank from moving forward.
If the crank does move forward, it is possible that the inside thrust washer can be pulled forward with the crank.
The problem is that the inside thrust washer has two locating holes in it that locate over two dowels in the engine case.
If the engine is turned even slightly with the thrust washer moved forward, it will not go back into position and when the
flywheel (clutch carrier) is torqued up...........oooh I can't bear to go on.

There are other possible causes for an oil leak from the rear of the engine besides the seals. If the guide ring is worn it will quite likely continue to leak even with a new seal. Most likely a seal, but check the guide ring too!

Thanks for the input fellars. Going to do the seals, so useing the existing g/box and
see how it goes, can't feel the shiny bits MS, just see them, the friction plate is good
Jeff, that was just some white grease in the photo, and that bolt idea is great, I was
going to use a block of wood, will check the guide ring. Yeah Charlie M/Bins are supplying
most bits, a couple from Ross though, Wirewrkr, thankyou, how long is the 6mm part? I'm
guessing about 40mm, will modify mine in a couple of days.

ME 109 wrote:There are other possible causes for an oil leak from the rear of the engine besides the seals. If the guide ring is worn it will quite likely continue to leak even with a new seal. Most likely a seal, but check the guide ring too!

I was able to polish out the slight wear line around it with a strip of denim and Autosol.
I also went with the new style main seal in hope it would contact at a slightly different point.
There is a large o-ring inside the guide ring (11221337099) worth replacing.
The oil pump cover o-ring (11411335895) is also worth replacing.
Seems to have worked out - no leak.

My guide ring has had two 'operations'
The first was to have it ground in a lathe. Fix him oil leak no worries fella.
The second op I had it turned in a lathe with a ceramic cutting tool. Made no difference to the oil leak 'cause it wasn't the guide ring, it was a cracked oil pump cover!

Case in point, the guide ring can lose some of its O.D. without failing.
Given the id of the RM seal and the od of the guide ring, I assumed correctly that there was room to move in 'dressing' the guide ring.
Still dry as a bone on the shelf.

Bob Bennett wrote:Thanks for the input fellars. Going to do the seals, so useing the existing g/box and
see how it goes, can't feel the shiny bits MS, just see them, the friction plate is good
Jeff, that was just some white grease in the photo, and that bolt idea is great, I was
going to use a block of wood, will check the guide ring. Yeah Charlie M/Bins are supplying
most bits, a couple from Ross though, Wirewrkr, thankyou, how long is the 6mm part? I'm
guessing about 40mm, will modify mine in a couple of days.

A trick I have used for blocking the crank is to fold a piece of corrugated cardboad in two (or four) and tape it to the rotor. It will crush to a good height. Easier than messing about with bolts.