14in Drum tolerance

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USAFpj
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14in Drum tolerance

Post by USAFpj » Sun Apr 21, 2019 6:48 am

Gents- the manuals are a bit vague on what is considered 'tolerable' and within specs for the 14in drums on my WC52. I found a local shop who is more than happy to work on them, and his adapters fit, but he needs to know to what's the maximum he can cut to ensure they can get turned correctly and not ruin the drum?

I'm across the world for a while, and would like for my Son to drop the drums off with the specs that I receive here on the Gee. May I ask what's the most common sense answer that I can pass to the mechanic?

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Re: 14in Drum tolerance

Post by dpcd67 » Sun Apr 21, 2019 9:58 am

You are only allowed to remove .015 as I recall; so tread very lightly here. It is easy to cut them too much, and off center. In which case your brake pedal will pulsate, which feels weird.
Which is why I never have them turned unless they are grossly gouged up; once you ruin them they are not easily replaceable. So, for me, and I have done several Dodges, I typically leave them alone.
And then, for best results you need the shoes arced to match; very few people know how to do that nowadays either.
Bottom line, I do not trust any brake shop that has not done lots of these particular drums.
I had one ruined by the RIA post auto shop and they had the correct adaptors too. It is not easy as a little toy jeep drum.
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Re: 14in Drum tolerance

Post by USAFpj » Sun Apr 21, 2019 10:28 am

I hear ya. My Dad is a machinist (but not a brake guy), and when he looked at them, only one of the four he felt was questionable. He felt the others were ready for service after a complete bead blast, paint, and new shoes.

Sounds like I may go with that, and spend most of my efforts on getting a good shoe adjustment and air free lines..

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Re: 14in Drum tolerance

Post by Ben Dover » Sun Apr 21, 2019 11:12 am

Original NOS GI Issue 0.030" Chrysler WWII packaged WC Lined brake Shoe sets are out there.
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Re: 14in Drum tolerance

Post by dpcd67 » Mon Apr 22, 2019 7:23 am

Where are they? I might need some.
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Re: 14in Drum tolerance

Post by Ben Dover » Mon Apr 22, 2019 10:31 am

I have them stored away. Chrysler and Wagner discontinued the new WC/PWlined shoes in the late 80's and I set some aside. Have to see if there are any spares and what size.
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Re: 14in Drum tolerance

Post by W. Winget » Mon Apr 22, 2019 10:46 am

If you do decide to turn the drums, they should be turned on the hub, screwed on, and with the bearing race in place. This is the best way to ensure the hub and drum runout will be minimal. Mark (with paint) the orientation and hub so they go back together if removed for service, better yet pull the whole hub assembly and leave the drum on the hub if servicing.

I had nothing but problems when the Virginia State inspection would come around and pull a drum, then reinstall it leaving me with wobbly brakes. I ended up switching to a 4 Disc setup and haven't looked back.
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Re: 14in Drum tolerance

Post by dpcd67 » Mon Apr 22, 2019 2:23 pm

Fortunately our state does not do inspections.
Joel, so by "out there" you mean, no parts vendor actually has any.
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Re: 14in Drum tolerance

Post by Ben Dover » Mon Apr 22, 2019 2:29 pm

Spotty. Memphis Equipment should have.
I'll only buy Wagner or OEM If I were to look.
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Re: 14in Drum tolerance

Post by W. Winget » Mon Apr 22, 2019 7:19 pm

Never followed up on mine, but what was the possibility of an M37 Drum VS a 3/4T M101 trailer drum fitting a WC 3/4T truck?
Might be some crossover possibilities. Parts books....
Just a thought.
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Re: 14in Drum tolerance

Post by Ben Dover » Tue Apr 23, 2019 6:17 am

Yes the Shoes interchange with WC and M-37, I have Puut asid some NOS M-101 Backing plate assy's just for the shoes. Backing plates are rigged for parking brake, good for scrap only.
Not so easy to do one stop shopping as the parts are heavy and are not delivered by the stork. Anyone priced NOS 14" WC/M-37 Drums lately?
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Re: 14in Drum tolerance

Post by W. Winget » Tue Apr 23, 2019 8:36 am

It's the drums that would be gold, M101 trailers have basically NOS drums unless they had a trailer brake set too tight or left on, there should be zero wear. I'm still not certain they would fit, (three lock screws, shoe depth?) but in a logical World the trailer would have identical hubs, bearings, races, brake shoes as the 3/4T & M37 since the same tire interchanged (depth of drum matches) and the trailer was designed about when the M37 came out.
Might be worth a test, worst case leave the worn out drums on the trailer and adjust the hand brake out to tension them up.
But then contractors can't sell their own replacement parts if they produce interchangeable stuff....
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Re: 14in Drum tolerance

Post by dpcd67 » Tue Apr 23, 2019 10:24 am

Brake shoes that Memphis has are not NOS; they are re-lined using glue on linings.
Just like everyone else sells.
So, good luck finding NOS, .030 over, M37 or WC linings.
I get mine from Vintage Power Wagons. Relined ones.
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Re: 14in Drum tolerance

Post by rjbeamer » Tue Apr 23, 2019 2:38 pm

Vintage Power Wagon has new repo 14" Drums. $170.00 ea

https://www.vintagepowerwagons.com/sing ... s-Are-Here

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Last edited by rjbeamer on Wed Apr 24, 2019 2:22 pm, edited 1 time in total.

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Re: 14in Drum tolerance

Post by Ben Dover » Tue Apr 23, 2019 3:50 pm

And I have only seen NOS lined shoes in standard and 0.030 for the Dodges. Asbestos is the norm for OEM and they work the best.
2011 MVPA PIONEER AWARD - MVPA #1064
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