Time for the Drum brake technote. This is how to replace the linings, drums, bearings, parking brake cables, and even replace a stub axle. This one has an excessive amount of pictures (132, actually!), so read on for the whole thing.
Lemme just lay out some things about drums and why you would bother keeping them …
- Drums are more reliable: no siezed parking brake mechanism
- Drums do not cost a lot to replace, unlike the disc parts
- Drums’ linings do not have to be replaced as often as pads
- Drums do not get brake dust all over your wheels
- Drums don’t make you have to upgrade your MC, or lines, or anything to use them
Here’s the new Brake Drums. Made by Zimmermann.
Jack up, and properly support the car. Take your wheel off. Find your crusty old drum there.
Grab the grease cap off, Since you have a new one, feel free to destroy it. Chanel-locks work good for this.
Un-bend the cotter pin, and take it out with some pliers, then remove the nutlock thing that’s sitting under it.
Clean the area with a rag.
Now, Remove the nut, and the Washer.
You can actually reach into the drum through one of the lug bolt holes, and push the adjuster bar up with a screwdriver. This picture shows where the adjuster would be:
Now, remove the drum if you can, making sure the parking brake is not on. If it won’t come off, not to worry: Just attach the wheel to the drum loosely, and use it to rip the drum off! 😀
There’s the inside of the brake. Looks kinda complicated, but don’t worry about it. Just do one side at a time, so you can see how it goes back together.
Remove these springs by turning the top 90 degrees to release it from the pin.
Once you have both out, go inside the car, and remove the parking brake cables from the handle. The nuts are 10mm, and there are two on each site, with one to lock. There is also a slot in the end of the cable to make it easy for you to use a screwdriver to loosen the nut.
Note how the nut is rounded, it fits into the bracket. The second pic shows how the bracket sits on the handle.
Now, use a large screwdriver to pry the bottom of the brake shoes from under the bracket.
Now, Remove the parking brake cable from the shoe assembley.
That’s a pile o brake. Save it nearby, so you know how to re-assemble it.
Look at that nasty wheel cylinder. It might leak, the almost always do. They’re cheap to replace, and it would be great to replace it while you are in here! This one shows signs of leakage as shown in the second pic. The third pic shows a broken bleeder screw. They almost always break. This is the main reason to get new wheel cylinders.
So, carefully remove the brake line, the nut is 11mm. Use a flare wrench.
Use a drain pan to catch all of the brake fluid.
Now, remove the old Wheel Cylinder. Two 5mm allen hex bolts hold it on. Use a socket, not an Allen key.
Now, Assembley is the Reverse of Removal…. 😀 Just kiddin’
Put the nice shiny new one in, and re-attach the brake line.
Now, comes the process of transfering the bars from the old shoes to the new. Take your time, and be careful with the springs. Follow this sequence of pics. Just make the new look like the old. If you want – take a few detailed pictures, or even draw a diagram for yourself of how the springs are routed.
Now you have a new Shoe!
Time to do the parking brake cables. These are good to replace. Unclamp and unhook them from the axle beam, then pull them out of the car where they come through the floorpan.
New cable. Installation is reverse of removal. 😀 Be sure not to bend the cable too much, that will break it.
Now, attach the cable to the new shoe assembly.
Now, holding the pistons in, put one side of the shoes on.
Now we have the new retaining springs and posts. Put em in on the rear side.
Now, use a screwdriver to make the other side go under the bottom shoe bracket thingy.
Now, put the other spring thing on.
Tap the adjuster all the way up with a screwdriver and a hammer.
Now, just center everything by tapping it with a hammer
Now, we have to drive the large bearing race into the drum. We used a cheap bearing driver kit for this.
There’s all the rest of the parts we need…
Driving the smaller race in…
Grease those bearings up as much as possible. Pack it in and squeeze it, spin the bearings, and make sure as much as possible is caked all over them.
Put the bearing in…
And install the inner grease seal.
Here’s one final detail pic before you put the drum back on…
Now, you’re ready to put the drum on!
Slide it on, making sure the bearings don’t fall out.
Next is the washer
Now, fill the grease cap with a bit of grease, about 3/8 oz.
Put the nut on by hand.
Torque the nut to 87 in-lbs while turning the drum with your other hand.
Now loosen the nut slightly. Tighten the nut in slow, small steps until it can be moved side-to-side with just hand pressure from a screwdriver – don’t twist or pry with the screwdriver.
Now install the nutlock so that you have a clear hole for the pin. If you need to, tighten the nut slightly to get to a hole.
Now install your new cotter pin…
Now, with a soft mallet, install the grease cap. Don’t worry about it if you dent it a bit.
Now, Flush your brakes out with lots of fresh brake fluid! You are done!