Rear Axle Seals

[Tom Skinner]

Gents,

I have had my Left Rear Inner and Outer Seals Fail and Soil my Brake Shoes several times in the last 18 Years.

I will use Rich's Advice to keep my Pumpkin 1/2" Low on Grease.

But also does it look like I have installed these Seals correctly over the years? See Attached

[Plymouthy Adams]

yes

[Veemoney]

I second the seals appear to be installed correctly. Have you confirmed the breather for the axle is not plugged up and also check the diameter of the axle wear surface for size that mates correctly to size of seal or pitting/grooves. I have also seen springs pop out of the seal during installation for those so equipped.

[Loren]

Another important thing is to use the grease fitting for the outer bearing. Some grease there will hold back the oil too. The bearing looks a little dry.

[desoto1939]

40 minutes ago, Loren said:

Another important thing is to use the grease fitting for the outer bearing. Some grease there will hold back the oil too. The bearing looks a little dry.

Loren: are you talking about the little plug on the axle near the backing plate on the axle?

According to my 1939 Service Manual they state to not use a zerk fitting because when using a grease gun the user has a tendency to put to much grease into this location and this then forces grease out the end of the axle shaft.

 

The instruction state to remove the small bolt then put some grease on your thumb and then press the grease into the hole so as to not over fill the area.

 

Rich hartung

Desoto1939@aol.com

 

[Tom Skinner]

Loren, 

It is dry only because I wiped it out. Rich is correct only a smear of grease on the rear Bearing is needed.

In addition as he pointed out earlier to fill the pumpkin a half inch lower than the fill plug. 

I cleaned my breather cap overfill on the axle constantly - what happens in intense Southern Heat - the Axle Grease Expands.

Thus the forced leakage. I am also going to smear some Indian Head Shellac Sealer on my spacer plates to insure no more leakage.

This changing out Seals and Shoes is getting old and expensive. I am shocked at how well the car stopped and braked with soiled Shoes.

They are going to be brand spanking new when I am done! Clean as a Babies Bottom with a fresh Diaper LOL!

Tom

[Loren]

I agree too much grease and you’ll have grease invading the brakes instead of oil.

However if you lube up the bearing it will help. As I recall there’s a plug and a grease fitting. If you grease up the bearing as you put it together you don’t need anymore.

If it’s altogether you might pull the plug and put one good shot of grease in the fitting. Pulling the plug allows air out so the grease doesn’t go out the seals.

Another tip: when you remove the backing plate, tap out the bolts holding it to the housing. The 5 bolts tend to hold the plate making it difficult to remove without scrapping up the threads.

[Tom Skinner]

Veemoney,

Yes I have confirmed the Diameters and Potential Pitting situation.

Also Thanks to you and Plymouthy Adams for confirming Position of Seals.

Tom

[Tom Skinner]

Loren,

I tapped them out. Thank you!

Been fixing these babies for over 50 years now.

They are a pleasure to service when done patiently and with care.

They will literally last forever if serviced regularly.

Tom

[Tom Skinner]

Thank you to all!

I need more feedback as I get older and forget stuff!

 LOL

Tom

[Kilgore47]

I have a question about the rear axel seals.  Yes I had to replace the rear brakes twice because I didn't clear the vent the first time.  

 

My question is - Can the inner seal be left out and let the oil in the rear end lubricate the bearings.  When I got the P15 I pulled the rear axels to replace the seals.  When I pulled the axels the bearings were dry, rusted and they fell apart.  This is an often neglected lubrication point.  

[Tom Skinner]

Kilgore,

I wouldn't leave out that inner seal, It will most assuredly (Pumpkin Grease) leak into and soil your Brake Shoes.

Just a smear of Grease in the Bearing area will hold it until you inspect it again over a 2 -3 year period. (usually when re-bleeding Brakes and adjusting them)

Lets face it - Service is mandatory on these old Buses to keep them running in top condition. Just as the Ignition System and Fuel System require that as well.

Tom