1951 Ford Brake Shoes

Admiral

Admiral

Well-known member
I'm getting ready to reassemble my 1951 Ford's chassis and had a quick question about the brakes. In a duo-servo setup, the LONG shoes go to the REAR of each assembly, right? I have the 1949-to-'51 shop manual, but it's nigh on impossible to tell what's what in the illustrations. Just wanted to double-check before putting everything together.

Thanks!
 
With self-energizing brakes the rotation of the drum pushes the rear shoe against the drum, so it does more of the braking than the front shoe. If you understand how they work, you will know why the long shoe goes on the rear. Grab the bottom of the shoes and move them back and forth and you will see how that rear shoe gets pushed back with the rotation of the drum. The rear shoe lining is longer and sometimes thicker since it does the majority of the braking. Bonded shoes are better than riveted. As the riveted lining gets thin it tends to crack from side to side along the rivets. The lining splits and break off and your brakes go metal-to metal. Bonded lining will wear down paper thin and still not come loose. I prefer Bendix Brake lining; it lasted the longest on our fleet vehicles. Make sure to put a little lube on the backing plates where the shoes slide on them. We used to use white lithium grease at work until the synthetic brake grease came out for sliding disc brake calipers. All the auto parts stores have it. Measure the drums and make sure they are safe to use. They should be machined with .010" of each other on the same axle to prevent them from pulling to one side. This important on drum brakes. Everything must be identical on both sides to have it stop perfectly straight with your hands off the steering wheel. Road test it with the original brakes first to see how straight it stops and again after your quality brake job. A larger drum, even if it's just thousandths of an inch has more rotational leverage. Most people if they have a really nice drum and a half worn out one are not going to want to machine that much off the good drum to match the other one. It might still stop straight, and it might not. Place the shoes against the drum and see if they are making full contact. They won't contact the same amount on two different size drums. They used to arc (grind) the shoes to fit the drums. Now you have to just wait until they wear down and make full contact or you can try sanding them to make full contact. I have two brake shoe arcing machines I need to restore. Very important, replace all of the springs, they start breaking after ten-years. Do not stretch them with any tool other than brake spring pliers. They can break if they get a nick on then from vide grips or other plyers. Plus, the brake pliers make the job so easy, especially popping the springs on and off the top pivot. It does this in a couple seconds. Flush all the old brake fluid out every time you do a break job. It's supposed to be done every two-years because it adsorbs moisture. If you do this, wheel cylinders will never get rust pits, Pull the rubber boots back on the wheel cylinders to see if they are starting leak, make sure the axle seals are not leaking. You don't want that fluid eventually ruining your new lining. Keep your greasy hands off of that lining, when your done it should still look like it did when it came out of the box. Lube the adjuster threads with anti-seize. If you have the drums or rotors machined, afterwards scrub them with soap and water A microscopic piece of that machined metal can get stuck in the lining and make it squeal. That is the number one cause of noise accordioning to a Bendix brake class I went to. Adjust the brakes up tight until it locks up the drum and then count the teeth as you back off the adjuster until it turns. Back the other side off the same number of teeth, you want to tr and keep everything the same on both sides. If you do a quality job, once you put that drum back on you won't be going back in there for years, decades on a collector car if you flush the fluid every two-years.

I was an ASE brake licensed mechanic, and I had 17 other licenses. ASE Master License and Master Heavy license. Smog license, factory Ford brake training. Bendix factory training Brakes are what I did the moist of at the phone company, thousands of brake jobs over 30-years.

How to use brake spring pliers

https://www.youtube.com/watch?v=9f7hpI5JvyE
 
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Flathead Fever, I agree, great write up about brakes. I have some questions. My original brake springs on my 52 sedan are purple/magenta. I just ordered springs from D Carpenter and they are yellow in the catalog picture. I ordered for all 4 wheels. Will yellow be a different strength than purple?
Also, when I got the car the brake lights were on all the time. I went thru 4 switches before getting a Harley C switch. But that did not fix it.
The front park brake cable was broken and I replaced it only to discover that the rear cable was rusted solid on both sides. When I finally got the rear drums off I found on one side the adjuster was frozen and the cross bracket jammed against the front shoe.. On the other side the swing arm was rusted to the shoe and the cross bracket return spring was missing half the loops and the cable end was rusted to the swing arm.
The rear cable is not manufactured by anyone. I was able to find a cable for a 60 Falcon that is the same length( approx 150" end to end ) I have new new rear drums and shoes. I cleaned the swing arms and de-rusted them. One cross bracket was not built correctly. The slots were undersized and would not slide into the new brake shoe notch. When held against the other bracket there was an obvious difference. I filed both ends to open the slots so they can slide easily.
Also, the backing plates were all rusty and I wire brushed and anti-rust treated them also. I changed all wheel cylinders , three flex lines, two crossover lines, have new rear drums and ordered new front drums. Also changed the master cylinder.
Whew!! Did I miss anything?.
 
Mea Culpa, Mea Culpa, Mea Maxima Culpa! I apologise for posting my problems on your thread. JPL
 
One thing to evaluate during a brake job that hasn't been mentioned is wear on the shoe support pads.

Grooves worn in the pads can cause new shoes to hang if not corrected.

The worn pads can be built up with weld and ground back to flat.

Thought I had a picture of a worn and repaired plate; but it is missing; found this one on the net instead.

This picture shows six pads on a 12" brake backing plate; most 10" & 11" brakes will have four along with the web of the shoe supported by the anchor pin support plate.
 

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rich b said:
One thing to evaluate during a brake job that hasn't been mentioned is wear on the shoe support pads.

Grooves worn in the pads can cause new shoes to hang if not corrected.

The worn pads can be built up with weld and ground back to flat.

Thought I had a picture of a worn and repaired plate; but it is missing; found this one on the net instead.

This picture shows six pads on a 12" brake backing plate; most 10" & 11" brakes will have four along with the web of the shoe supported by the anchor pin support plate.
Click to expand...
521280
 
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