Rear Drum Brake Agustment “Frozen” (1 Viewer)

[aktundra]

Replaced the brake master cylinder in my 1980 FJ40, after hours, in the parking lot of one of the national chain; brake/muffler/tire shops. Don’t have anybody around the house to pump while I bleed the brake lines, so asked the brake shop to bleed the brake lines and manually adjust the rear drums.

They said one rear drum was “frozen”, and could not be adjusted. Waiting for the rain to stop, and will take a look next week. I can replace the cylinder if that is the issure. Is there any trick to freeing up the adjusting mechanism, if that is what is “frozen”?

 

[igotta40]

I’m not sure about the 1980 rear brakes but on my 1974 the rear wheel brake cylinders are double acting, meaning the adjuster is also the wheel cylinder hydraulic piston. If that’s the case you’re better off just replacing the cylinder, in fact, all of them.

 

[Pighead]

Many years ago, when i still had drums on my 74 FJ55, i learned that Anti-Seize was my friend.
Put the Anti-sieze on all surfaces of your adjusters, especially where the alloy adjusters sit in the cast iron cylinders. Those dissimilar metals do not play well together.
Once i learned that trick i had easily adjustable brakes until i went to discs.

 

[peesalot]

Or the shop did not know how to adjust the brakes properly, FWIW x2 on frozen adjusters, mine were locked up as well, x2 on Pigheads advice to clean & grease adjuster surfaces will save you some headache.

 

[Living in the Past]

The cylinder can be frozen two different ways. I've had more problems with the adjuster frozen in the piston than the piston frozen in the housing. In past I have had luck with placing to two frozen parts in boiling water which two dissimilar metals expanding differently with heat has broken the bond. In AZ and not dealing with a block of rust.

I use a small amount of white grease on the adjuster thread. I thread the adjuster in and out a few times then wipe up any excess grease.

 

[Pighead]

I use a small amount of white grease on the adjuster thread. I thread the adjuster in and out a few times then wipe up any excess grease.

I don't like grease or oil near my brakes if i can help it. I just don't trust it. It seems to migrate when I'm not looking. Why i prefer the can of Anti-seize with the brush in the cap. It stays put and lasts forever. Some on the threads of the adjuster, some on the outside of the adjuster, some on the cup in the cylinder where the adjuster sits.

 

[POPO AGIE]

When I pulled the rear axle shafts on my rear axle the pistons were frozen the shoes were tight against the drums and had to work like hell to get the shafts pulled enough to get the C-clips out of the differential. Then had to beat and pry to they the drums off of the shoes.

The wheel cylinders had not been exercised since 1991 when all 4 wheels were locked up trying to slow down on a gravel road when I hit an F350.

 

[SteveH]

I had one adjuster on my '78 wheel cylinder that was so hard to turn (it would turn, but only with extreme force) that it was easier just to replace the wheel cylinder and apply anti-seize to the new adjuster before installing. All is well now. Now I don't dread adjusting the rear brakes.

Beware that before bleeding, you must manually adjust the brakes so the shoes drag a bit, or when you bleed them you will have trouble getting a firm pedal.