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Hi Packard people

I am busy fixing up my rear brakes and in the process had to remove the backing plates. The bearings seem fine, but I am replacing the oil seals.

My problem: how to set the bearing end play? With the new seals and the shims installed there is excessive in and out movement of the drive shaft - I would guess about 1 mm. Not the .004" -.007" specified. As I understand it this is set by removing or adding shims between the backing plate and the flange of the diff? In my case even if removing all the shims this play does not seem to get less? Will putting on the drum have any effect?

I really do not understand how the end play is set here. My biggest fear is that the bearing is not 100% correct as it seems to have been replaced previously. If the inner race is too thin can this be causing my problem? Can someone with a loose original bearing measure it for me?

Thanks a lot as always.

Regards
Barrie

africapackard,

I am pleased to see you doing service work on your rear axle bearings and seals. This service is often overlooked and can lead to damaged bearings and broken axles.

I recently did the rear brakes, bearings, and seals on my 47 Custom Clipper. Upon assembly I was concerned about how to accurately measure the axle end play. I didn't think there was any.

Looking at the service manual for procedure I noticed a tool that was pictured to measure the end play. Based on the one pictured in the manual, I fabricated the pictured tool to use. Note, the other short hex head tool is one I made to adjust the brake eccentric. The tool was made from some flat 1/4 inch thick metal stock. I drilled two holes, one large one to fit over the axle and a second one in which to insert the screw and nut. Actually, the large whole is not needed as you should be able to fabricated something similar that can be clamped with the axle nut.

The tool is placed on the axle, using the large hole, and secured with the axle nut. Next, the axle is moved in as far as it will go without using excess force. I tapped it, gently, with a rubber mallet. The new grease in the bearings will sometimes make it difficult to seat the axle. I then screwed in the screw until it just contacted the backing plate retainer and locked it into place with the lock nut.

I then pulled out the axle, by hand, and measured the distance between the screw end and retainer with a feeler gauge. It turned out my axle end play was in the middle of the specs.

You only need to do this on one side, one axle.

I made the gaskets between the backing plate and the axle housing, and the one between the retainer and brake backing plate of thin cardboard. I could have sprayed them with some clear lacquer or something else to seal their surfaces, but did not.

I reused the shims as they were when I disassembled the brakes.

I hope this helps. I expect you will get other suggestions as well. The end play is important in order to center the thrust block between the two axles. Good luck.

(o[]o)

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I probably should check the shop manual before I write this, but unlike the earlier AngleSet rear axles in which each axle must have it's end play set individually, as I recall the spec for the later axles is for both axles as a single assembly. Thus (within reason) you can make all the adjustment at just one side but you need to push both axles as a pair back and forth to get a true measurement.

O_D,

My recall may have been incorrect. I believe I checked the end play on both sides, but not as you described. I simply repeated the procedure for left and right sides. It probably measures the same, but not done to factory procedure. I'll check the manual too.

(o[]o)

Hi Barrie,

The procedure mentioned by Owen_Dyneto is correct. Checking from both sides as done by JW is also OK.
You should make sure that the bearing cup (the outer ring) is pushed all the way into the axle housing.
It is not very likely that the wrong bearing was used, but you should be able to tell from the numbers stamped on them. Timken and Bower numbers are the same - 25877 for the cone (the part with the rollers) and 25821 for the cup. You won't be able to see the number on the cone without removing it from the axle, but the cup number will be visible on the wider edge.
No need to install the brake drum for checking the end play.

Brian

As always the expert advise on this site is excellent.

I went out early to check and the story is:

The bearings is correct. It is an SKF make.

If you do this end play check, both sides back plates must be assembled otherwise the settings cant be done. My inexperience with rear axles is obvious! I could not understand the problem when only one back plate was attached. It seems as if both backplates should be attached before doing the end play check either side.

The book states: "End play of less than .050" can be adjusted at one side only. Remove shims from both sides if end play exceeds .050" in order to keep the thrust block centralized."

With both now attached the movement is much more realistic and I can now start checking for setup.

Hope this can help someone else in future. I presume there is only a handful of guys across the world that can claim to have done the end play on a Packard rear!

Regards
Barrie

You should make sure that the bearing cup (the outer ring) is pushed all the way into the axle housing.

That may not give a correct adjustment. Yes, both backing plates need to be installed to check the end play, but not the drums. But you don't press the cup in as far as it will go, you want it to be flush with the backing plate. If not, the forces of driving the car will eventually move it to that position which will increase the end play.

For cars with a single tapered roller bearing on each side, the best way is to leave the cup protruding a few thousandths beyond the axle flange and allow the tightening of the backing plate and shims if present to push it in so it's flush. Same on both sides, then give the far side axle a wrap with a hammer which will displace both axles via the thrust block to the near side; then go to the near side and check the end play. If you then give that axle shaft end a wrap to displace the axles in the opposite direction, you should get the same end play clearance reading on the other side.

Just to complete the picture for the earlier AngleSet rear axles using dual opposed tapered roller bearings on each side, each axle is fully independent with no center thrust block. Hence they are adjusted individually at each side via shims behind the inner cup (which can be a royal PITA), as shown in the following picture. If you have this style axle you might want to see:

http://www.packardclub.org/forum/viewtopic.php?f=15&t=266&start=10

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Wow Owen_Dyneto! What a story! At least mine is much simpler and easier to set up!

I road tested today and am happy to report WONDERFUL braking having looked at the ANCHOR PIN LOCK NUT and its stories in the official 1946 - 1950 Packard Service Manual. Cant be without this! Every time I learn a lot with this old timer! O, I had some help from a Bentley gut, but lets keep that secret!

Thanks all you Packard people from USA. One day you must come to Africa and we can do a visit to the Kruger Parkhttp://www.sanparks.org


Regards

Barrie

Barrie, I'm glad to hear you're a reader of the Shop Manual, seems many folks today want to skip that. And glad your brakes and axle end play are all successfully attended to.

As to coming to Africa, I once contemplated an interesting and somewhat unique Holland America cruise, from Cape Town to Tristan de Cunha, Ascension Island, St. Helena, and then on to the east coast of South America, up the Amazon, and terminating in Ft. Lauderdale, Florida. What ultimately turned me off on the idea was the flight times and logistics to SA - I'm a great sailer but a poor flyer. Until recently these islands were served by the last remaining Royal Mail Service line voyage from the UK, and is now replaced by service to Ascencion from Cape Town, to last only until an airstrip is finally completed on Ascencsion, scheduled for 2015, so my time left for such a trip is limited. Ship calls at Tristan de Cunha (the most remote occupied islands in the world) are now limited to just one or two visits a year. But perhaps .... the lure of new and obscure places still beckons.

Hi Owen_Dyneto

I do not know anything about the round trip or any kinda sea stories. I am about 2000 km's from the sea. But, you know what, we are getting a new boat to go to Antarctica if you want and we are very proud of it!
http://www.engineeringnews.co.za/article/sa-agulhas-ii-handed-over-to-sa-government-2012-04-05

You know, the names you mentioned sounds very adventurous, but I am also a poor flyer. A plane is just a bus with wings to me!

You must go to Trusthan de Cunha. As you say, the least occupied place in the world - mmmmm.

If you come by Johannesburg - please stay over at my place and that's an invitation!

Regards.

Barrie