26 rear end dust cover fitting problems

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Jim
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26 rear end dust cover fitting problems

Post by Jim » Wed May 05, 2021 9:57 pm

I have a 26 rear end in my car and have rebuilt it this winter and have it in very good shape now. However when I go to install the wooden split rim wheels the hub in the brake drum is rubbing hard up against the tin press fit dust cap and distorting it in at least 1/8 inch in. I've tried driving the cap on further but it is down hard and wont go further. I have been able to remove them without destroying them and flatten them out to almost original. I should mention that I replaced them because the originals that were on it were totally worn through and the hole in the cap is exactly the same size as the inner hub with some sharp jagged edges. The originals were installed with the felt under the dust cap.

I've been looking at the forums (older and post 2019) and have found a few references to dented dust caps but I'm not finding a solution yet. So far as I can tell I have everything together properly. I'm putting the steel thrust washer on first next to the axle housing and hyatt and then the felt washer and then the dust cap. I tried a shim of .015 and it won't stay in the hub and wants to squeeze out the back against the dust cap when installing the wheel, like there isn't enough room for it. I've checked the axle and it is at spec too. I thought maybe my hub was the problem so I tried the shim. I saw on one posting in 2018 from Dan Treace where the felt went on the outside of the dust cap and around the hub in the brake drum. However all other references seem to indicate it goes in the cap next to the thrust washer. If I put it in the brake drum it may allow the dust cap to drive on far enough but I'm not sure what keeps the grease behind the dust cap then.

I've put thousands of wheels on and off of other cars over the years and I can't imagine I'm stumped on such a simple procedure. Please tell me the simple thing I'm missing here.

Thanks in advance. jim

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DanTreace
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Re: 26 rear end dust cover fitting problems

Post by DanTreace » Wed May 05, 2021 10:16 pm

Check the length of the axle housing flange, as someone may have cut some off to fit floating hubs.

Measure the length of the axle housing flange outboard, and measure depth of the new dust cap. The smaller felt washer should be rubbed down with grease to compress its thickness, then cram that felt into the dust cup. The Hyatt bearing needs to be flush with the end of the axle housing flange, and then fit the steel washer over it, to protect the felt seal from the Hyatt.

The dust cap should seat completely on the axle housing flange. Needs a rubber hammer or soft mallet strikes sometimes to seat fully. I like to use a 1" dia. wood dowel to slip pass the axle and tamp it around and around until the dust cap is seated. Or you can use the end of the Hyatt Sleeve removal tool as the dia. of that pipe is ok for tamping on the dust seal.

A larger donut of felt is also placed into the recess of the brake drum hub, grease it too to compress. Work the grease into the felt, all felt washers need to done this way, don't fit them dry.
IMG_5375 (640x480).jpg
This wheel hub felt rides against the steel dust cap to prevent scaring of the cap.

Of course other like issues you have could be from worn hub taper and worn axle taper, or thrust washers that set the axle too far inboard, or the hub too far inboard.
The best way is always the simplest. The attics of the world are cluttered up with complicated failures. Henry Ford
Don’t find fault, find a remedy; anybody can complain. Henry Ford


speedytinc
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Re: 26 rear end dust cover fitting problems

Post by speedytinc » Thu May 06, 2021 8:43 am

Typically your problem is worn axle and or hub taper. This is a very prominent issue for small drum rear ends. Not as much an issue with a big drum. Every rear end i rebuild get the axles stretched. (lengthened .100") Do not use shims. They will work their way inward & destroy the outer seat. Outer seal cups take a lot of press to seat. Look @ the backing plate & drum edge relationship. The drum edge should be about flush with the backing plate. You can switch drums/ wheels & see if one goes on further than the other. May give you an idea of hub taper wear.


BHarper
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Re: 26 rear end dust cover fitting problems

Post by BHarper » Thu May 06, 2021 1:11 pm

speedytinc (John Karvaly) wrote:

"Every rear end i rebuild get the axles stretched. (lengthened .100") "

Okay. So, um, how is an axle stretched? Inquiring minds would like to know. I don't own an axle stretcher.


speedytinc
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Re: 26 rear end dust cover fitting problems

Post by speedytinc » Thu May 06, 2021 1:19 pm

The result of a "stretch" is to have more of the axle out to compensate for worn hub tapers. There are 2 ways to get this result. Buy a longer repop axle or move the axle gear further in. Here's how to "stretch" an axle.
Axle gear is pressed down. 2 - 1/2 round keys are removed. Key grooves are widened .100" toward the stub. Keys are replaced & axle pressed back down into the gear. Axle woodruff key tip gets ground flush to the axle gear base.(So bearing continues to run on bottom of gear face.) A thicker spacer goes between the axles when reassembled.

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