Rear Main Seal

[Anonymous]

I have a 66 Mustang with a stock 200 6. It has recently developed a massive oil leak from the rear of the engine, I am presuming it to be the rear main seal. I have two questions - 1. is there anything else I should check before I condemn the rear seal? 2. Can I replace the rear seal without removing the crank? I would like to know if it is possible to pull the pan and rear cap and push the seal out. Someone on another board said something about a "sneaky pete" but offered no further explanation. Any help would be appreciated!
Thanks, Importsmasher

 

[fordconvert]

There are a bunch of places in the back that could leak but if it just suddenly started the rear seal would be the most likely suspect if its for sure around the back of the crank. There is a rubber seal that sits between the oil pan and the main cap or timing cover. There is the pan gasket. There is the main cap itself. There are all the places where those parts meet. I bought a felpro full gasket set and it came with a 2 piece rear seal. I had the motor out of the car but didnt remove the crank. You have to remove the rear cap and then the new seal slid in fairly easy. The hard part is getting everything else clean and dry so it will seal up. I had trouble doing it in a stand with the motor upside down so I can imagine tryin it in the car. Im not sure if you can get the pan out without lifting the motor up a bit, I never tried. It took me 45 minutes to remove the whole engine and transmission so in my mind its not worth the trouble to try and work on it in the car.

Less common places to leak oil in the back would be head gasket, or the frost plug looking thing at the back of the cam shaft.

 

[Anonymous]

Thanks for the input. It is definitely coming from the rear. It doesn't look like the oil pan, as it is dripping out of the transmission bellhousing. AS for removing the pan in the car, it is actually easy. I had to change the pan once, and you just remove the cross bar and drop it down. I guess I will give it a try. If I have to pull the engine, I might as well rebuild it, and I don't have time for that now....
Thanks, Importsmasher

 

[yodabiri]

I have the same problem but mine only leaks when the car is stationary for a long time. I am planning to put in a rebuilt 250 engine into my 65 mustang but for now I just put up with the rear main seal leaking.

 

[addo]

Returning to the first post; generally I'd see the sudden onset of a significant leak as a cue to examine the motor's health.

It suggests an increase in blow-by, easily checked by compression testing. Replacing the seal may achieve very little if this is the case. OTOH, a minor overhaul in-situ may ameliorate problems for enough time to plan a more thorough repair.

Regards, Adam.

 

[Anonymous]

Well, this is a high mileage engine, but it has been very reliable. I plan to rebuild it eventually, once our other 66 Mustang is on the road (it's getting a 5.0/T5 conversion. It used to leave a couple of very small drops every so often, but didn't use a significant amount of oil. Then all of a sudden it starts puking oil, and it is coming from the bell housing area. It leaks a steady drip-drip while it is running. The engine runs the same, it isn't smoking out the exhaust (any more than usual!!) or fouling plugs. I don't know why it started, but I am tired of adding oil all the time....
Importsmasher

 

[mustube]

I used a little tool called a sneaky pete to change the rear seal without taking out the crank.

 

[Anonymous]

OK, you are the second person to mention a sneaky pete. can you tell me what it is and where to get one? I have never heard of this tool...
Thanks, Importsmasher

 

[Crosley]

OK, you are the second person to mention a sneaky pete. can you tell me what it is and where to get one? I have never heard of this tool...
Thanks, Importsmasher

this mayb? :

http://www.sjdiscounttools.com/kdt492.html

 

[fordconvert]

I think those tools were for the old style rope type of seals. When I did mine a few months ago I just removed the cap. The part of the seal in the cap was easy to get out just by pushing on it with fingers. I then used that part of the old seal to push on the part that was in the block under the crank. Once it broke loose so there was a nub sticking up I was able to pull it out easily. The new seal just slid in with steady even finger pressure. This is pretty much how all the motors I have done recently have been except for the chebbys with the 1 piece seals that look like wheel bearing seals. Maybe I just have been lucky and been removing newer seals? I do remember doing seals with my dad where they were rope like and there were all kinds of special tools to mash them in and pull them though.

I will point out that the 200 i just did is leaking from the back somewhere so I could be all worng. I dont think its the seal though, Im thinking its more of a oil pan issue. I should have spent a bit more time trying to get it straight.

 

[mustube]

I dont think I put a rope seal in but I could be wrong.

 

[fmartin_gila]

If it is a rope type seal, the sneaky pete is about the only way to change it without dropping the crank. Just remember to try to push it back in the groove cause when you pull it through, it will tend to stretch and shrink in diameter. If you don't push back, you still have a leak.
Fred

 

[Anonymous]

Thanks for the replies. So can someone clarify for me which seal is in my engine, the rope style or the rubber seal? It is a 65 or 66 engine (not original to the 66 car it is in).
Thanks, Importsmasher

 

[wallaka]

The OEM seal is a rope type. Replacements could be either; if it has been replaced there is no way to tell until you drop the main cap.

When you buy the replacement, buy the split rubber one. It is so much easier to deal with.