Trying to figure out how to remove the rear oil seal on my 70. 4.2

 

Engine and gearbox out I'm afraid. I believe with the series 3 you may be able to split them in situ just, but not sure about that. Probably easiest to drop the engine and gearbox then lift the car.

 

+1
This is a major job involving removal of the crankshaft, hence engine and gearbox must come out, and the gearbox, clutch and flywheel removed. So if you're going to do it, it might be best to convert to the later lip-type seal. You have to machine the crankshaft for this, as there is a scroll on the running surface for the old-type seal.

I think most people, having the engine out, would decide to overhaul the engine at the same time.

 

Assuming its the original rear seal - its a 52 year old piece of rope. I see from your signature that the car is a project. If the engine isn't run every now and again, the rope gets dry and leaks. They can "recover" somewhat with some use. If your engine is in the car, and if the rear seal is the only concern, I'd suggest maybe leaving it as-is until you've run the engine a bit. If you get into this, there's all sorts of "while the engine is out" type of considerations, including new clutch, re-surfaced flywheel, a bottom end rebuild with a crankshaft re-grind, new bearing shells, new thrust bearings, new big ends for the con rods, oil pump etc. It can definitely spiral out of control! Separately there's the consideration of new type of seal or old rope seal. I'm old school - I chose rope when I had the roadster engine rebuilt. It wouldn't be correct if it didn't leak a bit

HTH, Dave

 

Yes, there is the question of why you want to change it? Is it leaking a lot, or just a bit? If it's just a small drip I'd leave it until such time as I had to have the engine out anyway (such as needing a new clutch)

 

Other thing to mention is that if the car is parked on a slope facing upwards, and the oil in the sump gets to bathe the bottom of the seal, it will leak out. As well as the seal, there is a scroll on the running surface that moves oil forward when the engine is running. This scroll system was once common before lipped seals came out, for instance the engine in the MG Midget and Austin Healey Sprite is the same, except that there is no rope seal.

 

The real issue was finding out how to remove the seal retainer so I could free up the crankshaft . I could not locate the lower set screws that retain the upper cap for all the crap

Note drilled out set scews

Upper cap with resultant thread debris
Once I did I pretty much stripped out the hex screws head even using heat so had to resort to drilling the screw heads off to release the cap.