TR2/3/3A Identifying Rear Axle Leak Source

[mastaphixa]

My rear axle has a bunch of muck on the inboard side of the brake backing plates. Nothing inside the brake itself. I know the front seal had leaked in its previous live as there is ample evidence of the lube being thrown everywhere. If the tube seal, or the hub seal were leaking would it present in that way or am I just looking at more evidence of rear end lube that has been slung from the front dif seal?

 

[DavidApp]

What is the axle? Girling or Lockheed?

David

 

[Madflyer]

How much oil in diff. If low oil does not get to wheels so front seal @ drive line. If it did not get to brakes then oil may have run down axle tube , did car sit for a time. Clean drain refill to level to fill hole look again should not over fill. We TR 's do not leak we mark our parking spot.

Madflyer

 

[TomMull]

Sounds like it's been over greased. Clean it up and see if it's still leaks, good chance it won't. Tom

 

[CJD]

Grease, oil and slave cylinder usually leak inside the brake drum, down the outward side of the back plate. To leak on the inward side I'm thinking brake fluid or a bad gasket where the backing plate attaches to the axle tube.

 

[sp53]

I over greased those fitting once also, and, I think I saw it on the lube chart or just found them one day---- IIRC it leaked into the brake drum. I did what Tom suggested and cleaned it up, and it stopped plus I felt lucky. Probably need to grease them again because that memory is old.
steve

 

[mastaphixa]

Thank you all for your replies. To clarify, I have no lube or grease on the outboard side of the baking plate in with shoes, it is on the inboard side of the backing plate where the 6 bolts are that hold the outer hub in place. Its all caked there with years of dirt. Then moving inboard, the spring perch area is pretty clean and then further inboard is a real mess of caked goodness along with the bottom of the car which is no doubt the front dif seal leaking. I couldn't make sense of the grease caked around the end of the tube and back plate.

 

[CJD]

If the brakes aren't leaking then the seal between the axle and brake plate is bad. I don't see any way the pinion seal threw oil that far.

 

[mastaphixa]

John,
I am trying to understand the seal arrangement of my axle. I'm using the Moss Catalog as a reference. Mine has the six bolts holding the hub assembly to the tube. Please correct my understanding if I get it wrong. It looks like axle housing oil seal (7) seals against the axle shaft (36). It looks like that seal is supposed to keep the gear lube from passing outboard into the outer bearing(53). So on the inboard side of the housing oil seal (7) there is gear lube. On the outboard side of (7) is grease. Correct?

 

[sp53]

Is this the first time you have had the brake drum off, or how long has it been since you had the drum off? Perhaps the PO over greased the bearing. I think the suggestion of cleaning everything up and then waiting to see what happens would be a freebee.
steve

 

[CJD]

John,
I am trying to understand the seal arrangement of my axle. I'm using the Moss Catalog as a reference. Mine has the six bolts holding the hub assembly to the tube. Please correct my understanding if I get it wrong. It looks like axle housing oil seal (7) seals against the axle shaft (36). It looks like that seal is supposed to keep the gear lube from passing outboard into the outer bearing(53). So on the inboard side of the housing oil seal (7) there is gear lube. On the outboard side of (7) is grease. Correct?

You've pretty much got it. There are seals inside the axle tube to separate the internal oil from the external grease. Then there is a seal in the bearing housing to keep the grease from entering the brakes. What is not shown, and often doesn't seal well is the joint between the housing...the brake back plate...the shim pack...and the bearing housing. I don't know if they applied a sealer at the factory, or if the parts were just better mated when new, but there is no definitive seal. When I built my axle I used a bit of red anaerobic sealant when installing the shim and bearing housing to prevent seepage.

On the bright side, it is only grease, and it likely won't leak much unless the bearing is overfilled by the zerk.

 

[Andy Blackley]

I would not want to use a sealant on the brake baking plate/shim pack. If the oil seals are good its not needed. Even after the sealant compresses on tightening the six bolts it will throw off the free play measurement which is only 0.004 to .006, which is about the thickness of typical sheet of 20# bond paper.

 

[CJD]

Normally you are right, but in this case you have to seal the brake backing plate, 2 sides of a shim, the axle tube and the bearing housing...and there is no seal for this joint. In 60+ year old parts you will get a seepage if you try to depend on a straight metal to metal seal. Permatex 51813 anaerobic sealer is designed to seal metal to metal without adding thickness. It is used to seal the metal to metal 2 cycle motorcycle cases, where you cannot afford to add the thickness of a gasket, and the engine depends on the tight seal to maintain proper intake mixtures. Of course the leak in this case would be outside of the brakes, so it won't hurt anything if you can accept it.