rear brakes always applied

mcoomey

Member
I'm in the process of bringing a '30 Coupe back to tiptop shape after 30 years of storage. I rebuilt the rear brakes replacing most of the moving parts: shoes, rollers, cams, cam shafts, adjusting wedges, and adjusting shafts.

I now find that after putting the drums on that the brakes are dragging even with the wedge all the way out and the fish-eye clevis backed off of the brake rod as far as I dare. I can move the tire, but there is significant resistance.

Should I leave it as-is in the hope that the shoes will wear in or is there some adjustment that I'm missing? Perhaps grind a bit off of the adjustment shafts?

Thanks for any help you can provide. I am fairly new to the Model A scene.
 
If you installed the shoes without arcing to the drum or have new drums they need to be fitted. New drums typically are made ten-thousandths undersized and have to be turned, and the shoes need to be arced to the drum for a good fit. usually, they are a little too thick for clearance with new or low mileage drums. You can arc the shoes at home if you have some time, a sander and patience, but it is a long routine. Take the shoes and drums off the car, place the shoe onto the drum and see if the shoe makes complete contact with the drum, if not, use your sander to grind a little off 'til at least 50% of the shoe arc is making contact. then re install and drive and let the shoes wear down a little, they will eventually fit themselves to the drum. If you want to have the shoes arced by a pro ask around at your local club or at your favorite brake shop, they might still have an old arcing machine.
 
Thanks so much for the replies! I did not do anything to the shoes before installing them. I didn't realize that they had to be "arced". I'll take everything apart tomorrow and check the fit with the drums. I'm re-using the old drums, so hopefully it will just be the shoes that need work. Chalk this up as my first (of many, I'm sure!) lessons to be learned as I make my way through this restoration. Thanks, again!
 
Also assure that the shoes are centered. The vendors sell a device to check the centering or you can use chalk on the shoes to see where they are rubbing. The centering is determined by the tracks were the roller pins ride.
 
A little bit of drag is usable with new brake linings, and especially with woven linings. The linings need to wear-in to your drums. It is important that you setup your brakes with rods fixed at the factory length, except for the front brakes as shown in the attached slides. Start with the front rods at the factory length and increase the length to accommodate the 15-degree angle of the operating arms.

For those with Flat Head Ted's Brake Floater Kit, I found from experience that the brake shoe spring with the 2 coils must be used on the rear brake shoes to keep the bottom shoes from lowering and jamming the wheels going in reverse. These particular springs are noted as optional in the kit instructions, but use them.
 

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Thanks for the additional comments and suggestions. Thanks also to member Tim B. for his "Budget brake shoe archer" post from 12 years ago. It worked great and the drum now rotates easily allowing the adjustment wedge to do its thing.

I had read in another post that it was best to leave the center of the shoe a little high so it makes first contact, so that's what I did. If that's not the case I suppose it will wear even in time.

Now on to the left side!
 

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To check for the 15 degrees for the front levers, remove hub and rod. Then check that at 15 degrees the brake shoes are just starting to move. Add the shims (pills) to make this so. Re assemble and if you have to, adjust the rod so that the lever is at the 15 degree angle. Then adjust the brakes. Once the rods are at the correct length, do not change them again.
 
@katy:

Sorry, the forum won't let me post the actual clickable link saying: "To be able to post links or images your post count must be 10 or greater. You currently have 3 posts."

Perhaps you can copy and paste the following text replacing the $ signs with periods

www$fordbarn$com/forum/showthread.php?t=58970&showall=1
 
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