Jump to content

leather seals or new rubber (neoprene?) axle seals


Recommended Posts

The old axles that I've torn apart lately still have the leather seals.  They need to be replaced.  If I found NOS leather seals, would they still functional?  Are the rubber seals sufficient?

Link to post
Share on other sites

Depends on the set up.......leather packings tend to ride on a axel with a reverse spiral to push oil back towards the pumpkin. Rubber seals if available in the same size tend to not work well on shafts that have the spiral. Example.......early 30’s Cadillacs had leather, and rubber seals work as a replacement.........I would post photos of where you expect the sealing surface will be........and listen to what others have to say.

Link to post
Share on other sites
10 hours ago, edinmass said:

Depends on the set up.......leather packings tend to ride on a axel with a reverse spiral to push oil back towards the pumpkin. Rubber seals if available in the same size tend to not work well on shafts that have the spiral. Example.......early 30’s Cadillacs had leather, and rubber seals work as a replacement.........I would post photos of where you expect the sealing surface will be........and listen to what others have to say.

These axles have a smooth seat common to both bearing and seal.  I've read that the axles with leather seals were not typically vented and that the rubber seals do not allow a flow of air to equalize pressure.  Without venting, the pressurization can force oil leaks.

Link to post
Share on other sites

One suggestion on the Chevy site was to drill one of the top cover bolts length wise and install a cotter pin. This would allow the rear end to vent when using the rubber seals. Others install a vent in the top of the housing. When the time comes I think I am going with the bolt idea.

 

Dave

Edited by Dave39MD (see edit history)
  • Like 1
Link to post
Share on other sites

Every leather seal rear end I have ever seen was vented. With smooth axle surface, I would install modern seals if possible, just chuck the shaft in a lathe and polish it first.

  • Like 1
Link to post
Share on other sites

Chevy wasn't vented until 1937, and then the vent was in a spot that leaked. The cotter pin trick is right out of a 1937 Chevy TSB. It is probably available on chevy.oldcarmanualproject.com in one of the Chevrolet service news issues from that time.

 

My 1936 Pontiac, with it's Chevy-like rearend, isn't vented either. It will probably wind up with a cotter pin in a bolt eventually.

 

 

Edited by Bloo (see edit history)
Link to post
Share on other sites

My '53 forced fluid from the center section gasket after I switched to rubber seals.  A local long-time parts guy came up with using a brass fitting with the proper threads in place of an inspection cover bolt to vent the housing.  I ran a hose from the fitting to an open fuel filter and tied it to the frame so no junk gets back into the differential.  

  • Like 1
Link to post
Share on other sites

There is a part calles a Speedi-Sleeve made by SKF that can overcome the groves in axles (either intentional or wear). That will allow use of a modern rubber lip seal. Using a lip seal may require making an adaptor for the outside diameter of the new seal

DSC_3346.JPG

  • Thanks 1
Link to post
Share on other sites

One thing to keep in mind it that a modern positive seal will most likely leave grooves in the surface eventually, while leather (or felt) would likely cause less damage in use. It kind of boils down to "do you have an unacceptable amount of leakage, or not?".

 

In my case I am going to use a modern positive seal in the torque tube, because the "transmission oil seeping into the rear axle" problem (as seen in a few Chevrolets and Buicks) is something I don't ever want to have to live with down the road. I will be leaving the axle seals leather or felt, but preemptively adding some type of a vent so if the axle seals get replaced with a modern type later on, no drilling will be required.

 

 

Edited by Bloo (see edit history)
Link to post
Share on other sites

Old Leather seals tend to trap moisture at the contact surface and over many years causing pitting on the shaft that won't polish out.

...speedi-sleeve required if possible with modern rubber lip seals.

Otherwise use the leather seal soaked in oil on a slightly pitted shaft that cannot be replaced.

Link to post
Share on other sites

I've heard of using a sleeve on a rotating shaft where damage to the shaft prevents a good seal.  My axle shafts are in great shape so there is no concern for that.  What I have noticed is where the rubber type seal was used on a 70's era car and repairs were needed in the early 80's, the shaft had wear at the rubber seal.  The car had 50 to 60k miles on it, most of the failure requiring the repairs was related to rust.

 

My continued search finds the following product, also used on engine crankshafts, both fore and aft.  If I carefully remove the old seal, I may be able to pack it or reload it with a packing seal.  Has anyone ever tried this?

 

https://www.mcmaster.com/shaft-seals/abrasion-oil-and-water-resistant-packing-seals/

 

Link to post
Share on other sites
18 hours ago, DonMicheletti said:

The Mc Master packing is just that - pump shaft packing. I have never heard of it being used as an axle shaft oil seal.

The gasket set for the 1940 Buick uses this material for the rear main seal and the timing chain cover seal.  My initial concern was the serviceability of this packing at axle speeds.  However, the engine rpm is 3 to over 4 times the rotational speed of the rear axle.  

Link to post
Share on other sites

The packing will not work.......it needs to be in compression, or it will fall apart......and you do not want that. I have replaced leather and felt seals countless times, with no issues......over thousands of miles. My Cadillac’s were all upgraded to seals.......and so are my Pierce Arrows. My 36 V-12 has thirty thousand miles on the new seals, and are fine thirty two years later. Often times when replacing leather seals.......you have room for two modern seals..........so I install two of them, packing grease in between them..........works great.

  • Like 3
Link to post
Share on other sites
4 hours ago, edinmass said:

Often times when replacing leather seals.......you have room for two modern seals..........so I install two of them, packing grease in between them..........works great.

The Buick has an inner and outer axle shaft seal.  Any harm in using two outer with no inner and giving the outside axle bearing access to the differential lube?

Link to post
Share on other sites
59 minutes ago, kgreen said:

The Buick has an inner and outer axle shaft seal.  Any harm in using two outer with no inner and giving the outside axle bearing access to the differential lube?

 

 

Can't do it....you will pump the pumpkin dry.

Link to post
Share on other sites

Discovered that the front seals were felt.  Buick recommended they be replaced each time the hub is removed.  Again, the new repro seals are rubber.  I have found some NOS seals in two versions, with the metal retainer and felt only to replace that which is in the retainer.  @edinmassWhat are your thoughts on the felt seals?

Link to post
Share on other sites

They are fine.......you would probably have to do machine work to change them.......not worth the effort if you can't do it in house. 

Link to post
Share on other sites
On 10/30/2020 at 7:18 AM, edinmass said:

They are fine.......you would probably have to do machine work to change them.......not worth the effort if you can't do it in house. 

Yep!

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...