Rear main seal

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Jayro

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Hey guys,

As per an earlier post, I’ve got an oil leak on my 351 Cleveland and it seems to either be sump or rear main. Just had the mechanic call to discuss my options.

He is saying if it’s a 2 part seal all good but if it’s a rope type seal them engine out, crank shaft out and more of a major job for engine rebuilder.

Apparently know easy way to tell until they start stripping it down.

This all sound about right?

Cheers
Jase
 

boilermaster

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71 fastback
Jayro,
Sorry the rope seal is also a two piece seal, start looking for a shop that knows clevelands.
One can easily switch from a rope to neoprene just by removing the small spike in the center of the main cap.
The neoprene seal should also be clocked so the seal ends are not exactly where the lower cap and block meet.
Before expecting a rear main seal to actually (seal ) a good tech should also make sure your crankshaft end play is within specifications, if your shop does not know these things expect failure.
Boilermaster
 
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1971 Ranchero
You can't tell until you get the rear main bearing cap off....at least not that I know of. A rope seal can be replaced (with neoprene) without pulling the engine, but getting the upper half of the seal out and cleaning is less than ideal conditions. I can't blame the shop for not wanting to do it. Compressed air can help float the upper half out. So, yeah, it can be done, but it's harder to remove the upper half if it's rope.
 
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1972 Mustang convertible, 351C 2V with FMX (#'s matching)
Currently equipped with 351C 4V 4BM, .060 over, roller cam, Sanderson block huggers, -AC
Hey guys,

As per an earlier post, I’ve got an oil leak on my 351 Cleveland and it seems to either be sump or rear main. Just had the mechanic call to discuss my options.

He is saying if it’s a 2 part seal all good but if it’s a rope type seal them engine out, crank shaft out and more of a major job for engine rebuilder.

Apparently know easy way to tell until they start stripping it down.

This all sound about right?

Cheers
Jase
Jase,
I thought you mentioned it was leaking from the fuel pump area but now that it is the rear main seal I would agree with the advice from Boilermaker and bail on the shop you are currently going to and find a wrench that knows the Blue Oval engines. Since you have a bloak/mate in your neck of the bush, try to hit up Clevo King as he shares good knowledge on his SM sites and I would guess there is a way to contact him directly to assist you in all your mechanical issues. 🤔
 

Jayro

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73 mustang baby blue with clevo 351
Jase,
I thought you mentioned it was leaking from the fuel pump area but now that it is the rear main seal I would agree with the advice from Boilermaker and bail on the shop you are currently going to and find a wrench that knows the Blue Oval engines. Since you have a bloak/mate in your neck of the bush, try to hit up Clevo King as he shares good knowledge on his SM sites and I would guess there is a way to contact him directly to assist you in all your mechanical issues. 🤔
No mate never had an issue around fuel pump at all. Finally located a local mechanic today who is in this area of old school cars. He is going to sort the tuning, oil leaks and I’ve got a full new exhaust going on, he’ll run the new trans cooling lines then I’ll install the air con and we should be done ……..hey you gotta be positive right lol
 
Joined
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1972 Mustang convertible, 351C 2V with FMX (#'s matching)
Currently equipped with 351C 4V 4BM, .060 over, roller cam, Sanderson block huggers, -AC
No mate never had an issue around fuel pump at all. Finally located a local mechanic today who is in this area of old school cars. He is going to sort the tuning, oil leaks and I’ve got a full new exhaust going on, he’ll run the new trans cooling lines then I’ll install the air con and we should be done ……..hey you gotta be positive right lol
Yes, I just saw that it was Retired 2014 with the fuel pump story. Glad to hear you have a new guy but please keep us tuned in on the rear main seal saga. Gaday!
 
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So, it sounds like you've determined it IS the main seal leaking and not from v/c's or anywhere else up top.
As we still don't know exactly what year 351C went in your car, I'm guessing it is a rope seal as was the one I had to change on my 4/72 Mach 1 (back around 1982) I did this with the motor in and only on jack stands. On a hoist, it wouldn't be as hard. However, if I had to do it again, I'd pull the motor. It really is not that hard to pull a Clevo. With a good 2 ton hoist with a long enough arm to reach over the front bumper ( so you don't have to pull all that off too), that motor could be pulled in less than 2 hours. Problem with that scenario, you'll start finding other "stuff" to fix, clean up or paint!!
Anyway, here's wishing you good fortune moving forward.
 

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