Engine and Transmission Tech

I need to know the diameter of the flywheel mounting flange on the early 3.5 V8 that used the rope seal. I am trying to determine if later motors with the one piece seals have a larger flange diameter.

To what end?

Because I have a modified 4.6 Rover crank to go into an early 215. If the flange is the same size as the 215, then the rear main seal for a rope seal 215 will work.If the 4.6 flange has a larger diameter, then the easy solution is to turn the 4.6 flange down to the 215 dimension.

Unfortunately, the only 215 crank I have, is installed in my MGB. I can't seem to find a pic of a 215 crank for comparison, either. I was thinking that when they went to the one piece seal that the the crank was machined a bit different in that area.

Maybe someone will come along with some pics.

The real visible difference at the rear of the 4.6 crank is the lack of the oil slinger ring. Apparently the one piece seal would make the slinger ring unnecessary. This motor has defeated me. After 3 tear downs , 2 rubber seals from D&D and a new rope seal, the thing is still leaking. The rubber seals on both tries lasted about 15 minutes and then started leaving a puddle. The rope seal began leaking immediately but no where as bad as the 2-piece rubber seals. I thought maybe the 4.6 crank seal surface was of a greater diameter and therefore putting too much pressure on the seal.
The only thing I know to do is machine the back of the block and install a Rover one piece seal.

Jon,

I have an extra 215 crankshaft out in the shop and I'll try to remember to bring a micrometer home from work to measure it with.

In the mean time the block in my car was originally machined by Phil Baker and he machined the rear for a one piece crank seal. The seal part # is a National 417433 with dimensions of 3.250" ID x 4.003" OD x .375" deep. So I'm guessing that the crank would be around 3.250".
Not sure what the original application is for the seal, but I seem to remember Phil telling me that it was for a tractor of some sort. (It was a long time ago)!

Bill

Tractor?! Maybe a Triumph. ;)

Actually, it seems to be a multi-purpose seal that works in many applications.

No need for a tractor seal. All late model Rovers use a one-piece seal that is readily available.Since my 215 has a 4.6 Rover crank, the Rover seal would be right for this rear flange. This answers my original question regarding the diameter of the 215 crank flange. If the 215 crank is 3.25, it is the same as the 4.6 I measured it at 3.243 after a small clean up cut , So the seal failure is not due to an oversize seal journal surface.The Rover seal measures 3.15".
Now, WHERE IS PHIL BAKER???

Just now got a call, found some rope seals gathering dust in the back of an old auto parts store. Owner, thinks they are asbestos.
Maybe this is worth a try. Back in the day,( please excuse the cliche) rope seals were removed without removing the crank with a tiny cork screw type device and the new seal was pulled thru using the same tool. However, the 1961 factory manual says to beat the seal into the groove.

I just measured it and it's 3.246" at the sealing area. It does have a slinger on it.
I have seen other engines with a 1 piece seal and a slinger as well. If your 4.6 crank doesn't have one, it's possible that maybe a 4.6 block used some other type of "shield" incorporated into the main cap.

Sadly I believe that Phil Baker passed away a number of years ago. He had a machine shop in the Seattle area and was the 215 guru back in the day!

As another possibility to your leakage problem, Is it possible that the crankcase ventilation system isn't doing it's job?

Thanks for the pic and measurement.

Adding a slinger has been discussed. Tack weld an .060" ring to the crank, either mig or tig, which ever puts the least heat into the crank, however, there are other cranks without slingers but they have one piece seals.
Put my first motor together in the 70's, and NEVER had a rear main seal leaker.

Crankcase venting is good. PCV hooked up and flowing. This motor has only 45 minutes on it after a crank re-grind to reduce clearances and show decent oil pressure. Cured the oil pressure problem. Total rebuild only 500 miles ago. Third time assembling.

Will post new thread requesting name of experienced machinist to machine the block for a one piece seal.

Please Stop, and look at you're future slippery drive-way ! Rope seals belong in the "buggy whip" section , of a museum. Counter bore the early block to take a 1 piece late seal and never look back, or under....