Rear main seal

[31 RPU]

Has anyone tried the modern nitrile rear main seal? You have to cut the rear slinger off the crankshaft.
Does anyone use have any comments for or against it?

Thanks


*Looking for left and right front running board brackets*

[BRENT in 10-uh-C]

At this time you may want to steer clear. Several of us have had issues with rear seals and now the trend is to go back to the original method with the slinger.

[31 RPU]

I did hear that there was some heat buildup from the seals that caused problems with the rear main Babbitt but I wanted to get more opinions.

[George Miller]

After working in hydraulic plant for many years. We built up to 24" bore cylinders.
I do not think the seals are made right. If you look at the lip seal in a modern car and check it against those seals you will see it does not have the same style lip.

With that said I did try them, two worked and two did not. I no long use them.

[Jazzjr]

I had the slinger cut off a good running motor, that puked oil from the rear main,4 years ago. When I tore it down to Plasta Gage the Clearances were within limits. I used the Terry Burt Nitrate Seal that Snyder's sells. It lasted about 500 miles and started leaking bad again. Again I tore it down, some how the seal had a nick in it. I contacted Terry and he had designed a 2 piece felt seal to replace the Nitrate one. He also told me to use Number 2 Permatex, to seal everything around the Rear Main Cap, up the Bolts, and threads and etc. It cured my leak, I ran 1750 Miles last year, and just a normal 3-4 drips when I shut it down. I just arrive here in Florida last week, been using the car, about 125 miles, everything is normal.

A-2 pc. style cork/neoprene accessory rear main seal. The slinger on the crankshaft has to be machined down to 2.090"/2.100" in order to use this seal. We have found that some people have trouble using our other 1 pc. neoprene seal (A-6336) if the crankshaft has been turned to the low side of the tolerances specified in their instruction sheet. Fits 1928-31 A's. Installation instructions included. U.S.A. A-6337 2 Piece 1928-31 $16.95 / ea.

[MikeK]

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Modifications for 'modern' seals (any, including rope!) are not worth the bother unless you are pressure feeding the rear main with no flow restrictor. A's didn't gush when new, only a polite drip or two when parked. The puddles everyone seems to associate with an A are the result of less than factory attention to detail on assembly. I have one A that I rebuilt with a stock slinger 5 years ago, running synth oil which some people claim leaks like crazy, and the rear main passes so little I worry about the wishbone ball going dry.

[Mike V. Florida]

Originally Posted by 31 RPU

Has anyone tried the modern nitrile rear main seal? You have to cut the rear slinger off the crankshaft.
Does anyone use have any comments for or against it?

Thanks


*Looking for left and right front running board brackets*

Mine leaks like there is no seal there at all.

[Rusty Homestead Fl]

Just a curious question. Once a rear slinger has been machined off is there a way to reinstall one or is it "replace the crank" time.

[George Miller]

Originally Posted by Rusty Homestead Fl

Just a curious question. Once a rear slinger has been machined off is there a way to reinstall one or is it "replace the crank" time.

You could weld it up and have it turn back to a slinger, but would not be cheap.

[ursus]

There seems to be a wide range of answers regarding the Burtz Nitrile seal. I guess a corollary question here is: has anybody had experience with using the cork composite rear main seal that was depicted earlier in this thread?

[olut]

Hi guys,

I am now in a similar trouble like many others of you. The mechanic, who worked in order of the previous owner on this vehicle told me, that leaking is normal, it takes time, that seal soaks oil in order to work properly.

The leaking is about 1 Liter/150km (!!)

Fact is, massive oil comes out from the clutch house whole, as long as the engine runs. Finally my new mechanic, who cares for all my Landcruisers, took out the engine and opened the oil pan. Fact is further, there is no seal, it seems to be the very first type of crankshaft using the slinger ringer but no seal (which cannot be installed as long as there is this slinger).

So I decided, to get rid of the slinger and install the two piece kork/neoprene gaskets as I did not want to start with a new crankshaft without slinger. I also decided not to go for the latest version of seal.

Your opinions are highly appreciated about my decisions....

Basically I am running out of options, because all advises in this forum have been followed, the fact is, that the slinger obviously does not spray off the oil efficient enough or, due the recommended viscosity of the SAE40-Oil it flows off back into the pin too slow....

Many thanks in advance to take your time to respond to me, cheers from Austria, Albert

[Kurt in NJ]

Metal once gone is hard to put back.

Do you "top off " the oil level every time you drive ----does the amout of leakage change when the oil level is low

Do you get oil spray out the oil fill cap ---have any modifications been made to it

If it is apart post pictures of the parts

There are many cases of leaks that don't go past the slinger ---replacing the slinger system with a seal won't fix those

[Sparky]

Albert, it is not clear (to me) from your post whether you still have the original oil slinger on the crankshaft or it has been machined off.

[Terry,NJ]

I read this thread with great interest as I have an engine that runs strong in every other way, but "pees" out unacceptable amounts of oil. This was my first Mod. A engine. I had new mains poured and they're tight. I thought I was being careful when I reassembled it. I know that it didn't leak like this when it came out of the Ford Plant, so what am I doing wrong?
Terry

[olut]

Thank you guys for your quick response.

The leaking is independent from the oil level, at least, it appears to be so. I do not have over pressure in the engine, although there are new pistons and not yet many miles on it.

The slinger seem to be original, as the entire engine was, before the previous mechanic installed adjustable valves.

There is no axial clearance of the crankshaft, the main bearings are an great shape but look original.... possibly.....


The only way to reduce the oil leaking is to drive the vehicle under very cold conditions....

Basis of my decision to remove the slinger was, that whatever I do, it can´t get worse, the untrue information of the previous mechanic that he had fitted a new gasket, although this is impossible with a slinger and that in this forum there is a mathematical higher chance, that this modification will at least reduce the leaking... :-) fingers crossed...

Albert

[1931 flamingo]

As long as engine out ck for gasket over camshaft in the rear. Is the tube on the rear cap in place??
Paul in CT

[olut]

Originally Posted by 1931 flamingo

As long as engine out ck for gasket over camshaft in the rear. Is the tube on the rear cap in place??
Paul in CT

oil return tube was in place and is not blocked, my mechanic told me. He´s got all repair books of this car and I advised him to have a sharp look exactly on this matter, as this is often one of the reasons of heavy leaking...

gasket over camshaft in the rear not yet checked, will do, thank you

Albert

[Sparky]

Originally Posted by olut

oil return tube was in place and is not blocked, my mechanic told me...
Albert

I had the same problem as yours. During troubleshooting I removed the main cap and put some oil in the drain hole and observed that it flowed out the drain tube so I assumed it was OK, but the leakage problem remained. After further research here on the Fordbarn I removed the main cap again, and drilled through the plug on the end of the casting. I found that the oil passage in the casting itself was nearly closed with gunk and bits of babbitt; oil could drip through it but not fast enough to handle the flow from a running engine. I cleaned it out with a drill and re-capped the end with a small freeze plug, and haven't had a leakage problem since.

[olut]

Thank you Sparky, will Check accordingly

[olut]

Some pics