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Kevin;

The fit of the outer race to the housing is 0.0005 tight to 0.0015 loose. Given that a loose fit was considered acceptable I would first slide the outer race into the housing and evaluate the amount of ‘slop’. If you have a narrow set of feeler gauges and you can slide a 0.002 gauge into the space between the race and housing then placing the described punch marks in the housing would be warranted. If there is zero galling and the race condition is more of a ‘frosting’ then I would not ‘knurl’ the housing. I would not use a Locktite product near an unsealed bearing, nor would I be aggressive in producing a tight fit. The intent is to allow the race to slide and abut the backing plate during the clearance checking procedure.

This subject of race/housing clearance appears on page 4 of the service manual supplement I attached to one of my previous posts. I’ll add some guidance on requalifying the bearing bore if the clearance is found to be excessive.

dp

Just re-read that portion of the document David, thanks for the reminder. I had read the whole thing prior to removing axles, but it makes a lot more sense now that I have completely disassembled the axles and seen the inner workings for myself. I'll see if I can check the slop with a feeler gauge.

It's hard to know what the initial problem was. Did the race spin first, heating things up and cause the inner seal failure? Or did the inner seal fail first, and get gear oil all over the bearing and race, leading to spinning the race? Does it matter?

-Kevin

Kevin:

I’m not really sure how to evaluate GL-5 being introduced near the outer diameter of the race. On one hand the coefficient of friction would be reduced and the bearing would/may rotate with a lower level of torque . . . torque coming from bearing drag. Countering that would be the general tendency of the oil preventing marking/galling/scoring of the parts. You may really have nothing more than an exhibit for Ross’ no fun with used cars.

Unless the bearing fit wildly in excess of the 0.0015 limit I would believe the seal damage is not related to the loose bearing fit. It is an interesting situation in that all lip seals need some initial lubrication, and some sustaining lubrication to avoid rapid wear. Given that GM was using a ball bearing in the same location, and this bearing was sealed on the outboard side, and unsealed facing the differential. That design clearly used the differential oil to lubricate the ball bearing, therefore the rear axle seal on the Packard is likely lubricated by the differential oil, not the grease applied to the bearing.

Now let’s talk about seal life and bearing clearance that involves the shims. As the clearance is increased additional deflection will occur at the seal, and that deflection is with the axle deflected upward. If the seal wear appears near 12 o’clock that would be an indication the bearing clearance at one time was on the high side.

I’ll take another walk through the Packard service information looking for advice on initial lubrication of the inboard seal. I know there is guidance on not applying ‘extra’ grease on the shaft or housing. From that I’ve drawn the conclusion that the interface between the housing and outer bearing race should not be lubricated . . . at least with grease. I normally wipe the surfaces with grease, and then wipe them clean, which is more of a rust preventative step than lubrication. If I can’t find anything in the Packard stuff I’ll craft a sentence or two on the in the supplement.

I would wipe the entire circumference of the seal with GL-5 just before the axle is installed, and apply some on the axle shaft from the spline to the point where the seal rides . . . not beyond.

While you’re checking the fit of the bearing in the bore try several location, meaning different ‘clocking’ positions, and if the feeler gauge check is conducted try a few different locations . . . . just trying to figure out if the housing bore is round or egg shaped.

dp

I didn't lube the seal on the passenger side because I couldn't find anything about it in the literature. I did find, as you pointed out, that Packard recommends not putting additional lube on the axle shaft.

The axle shaft (both of them) had a coating of gear oil on them when I pulled them out, which remained when I put the passenger back in. I wonder if that will be enough to lube the inner bearing flange? Otherwise I will need to disassemble the passenger side again and lube the seal.

-Kevin

Kevin;

You can cross the passenger’s side seal lubrication issue after you have an idea of the bearing clearance. As long as you didn’t wash the gear oil off of the axle then I would think you’re OK . . . some amount will get there in very short order.

dp

Some progress today, but not as much as I wanted.

I cleaned all the parts for the driver rear brake. Sandblasted all hardware, repainted all of it, including the backing plate. Cleaned the drum from all the grease and oil as well.

The new brake shoes were checked against the old ones, and they are mostly a match. An extra hole, but that is no problem. The webbing is a bit thicker on the new shoes (as warned). I will need to thin out the areas that the adjusting screw and parking brake adapter fit. The wheel cylinder cleats fit fine.

Next I cleaned out all the old contaminated grease from the bearing on the driver side. It was pretty bad. But got everything out, cleaned and dried. Then packed new grease from the back until it oozed out the front.

Then I cleaned the bores in the axle housing and installed the new inner seal. I put a bit of gear oil on this seal because I had wiped off some of the oil on the shaft while handling it for bearing grease removal. Slid the axle back in, and tapped the bearing race in. After looking at it again and reading over the document David posted earlier, the race is supposed to move out against the backing plate. Once I cleaned everything up, the race was actually a tight fit, so I did not feel the need for knurling the inside of the housing.

Then I spent the next while trying to make sure I was doing the axle play measurements right. I made a measuring tool, and followed the instructions in the document. The passenger side had only a single thick shim, while the driver's side had two thick and two thin shims. I went ahead and moved the two thin shims to the passenger side to even out the shims as much as possible. Following the directions I ended up with ~0.006" of axle play according to my measurements. I measured both sides for kicks.

So both backing plates got installed and the bolts torqued to 35 ft/lbs.

Then I got a call from NAPA, saying that they were able to turn one of my rear drums, but the other one is warped and they can't turn it. Awesome.....so now I guess I get to find a new drum?

Frustrated, I turned my attention to something else. I made new brake lines for the rear axle and made a couple decent double flares. I cleaned up the diff breather and junction block as well. I'm pretty sure the clogged breather was the cause for the original axle seal failure. I made up most of the line from the rear to the front, but just need to finish one more flare.

So, now I need to find a drum before I can finish this.

-Kevin

Attach file:

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  New rear brakes shoes.jpg (166.24 KB)


  New rear brake shoes comparison.jpg (159.63 KB)


  Contaminated grease on axle.jpg (112.15 KB)


  Bearing cleaned.jpg (125.58 KB)


  Bearing repacked.jpg (100.29 KB)


  New inner seal.jpg (135.45 KB)


  Reinstalling driver axle.jpg (153.73 KB)


  Shims from driver side.jpg (135.86 KB)


  Axle play check tool.jpg (137.36 KB)


  Backing plates back on.jpg (146.58 KB)


  Learning how to double flare.jpg (91.90 KB)


  Clogged diff breather.jpg (111.63 KB)


  Breather and junction block, new lines.jpg (100.01 KB)

Quite a bit work done. Where did you purchase your line and fittings from, if you don't mind me asking. Did you go with stainless?


- Anthony

For the thicker shoes, the adjusters are pretty much universal so your local Napa store might have replacements that can handle the thicker web while otherwise being the same size.

Anthony - I just picked up pre-made lengths from NAPA. They come in varying lengths, and have flares at both ends and fittings installed. You can just use the lengths they have a bend extra curves in them if you don't want to cut them down. I chose to make mine look pretty, so I cut the excess length and flared.

I think it's just steel line, but it's polymer coated on the outside to prevent corrosion.


Don - Good to know. I'll probably just grind a bit of thickness from the webbing with a Dremel. Easy enough and will save a trip down to NAPA, plus they will probably have to order them anyways. They almost never have what I need in stock.
-Kevin

Looks like the drums for the Panama with 12" brakes are specific to only that model. My chances of finding replacements are slim. Can warped drums still be used?

-Kevin