Drum Brake Repair

Due to recent finding that some people aren't really sure how to repair their drum brakes I figured I would do a write up on the job. In reality once you have seen how it is done once it isn't that bad. This thread applies to drum brakes on subaru's with the ej engine and select other makes(such as gen 3 vw's). If you have a different make then this may not apply.

General tools:

Sockets

Wrenches

Hammer

Thread chasers

Paper towels

The tools specific to the job:

Brake spoon

Flare nut wrench

Diagonal cutters

Brake cleaner

Brake fluid

Dial Calipers

Techniques without the tools made for the job:

Brake spoon = bent flathead screwdriver (look at the one in the video you showed us... has quite a bend on it)

Flare nut wrench = vise grips (may ruin the nut so be careful)

Make sure the car is stable.

Removing the drum:

Remove the wheel

Find the slot on the backing plate and insert brake spoon

There is the adjusting wheel that needs to be backed off(screwed in to shorten it) to allow the drum to slide off

Once there is no contact between the shoes and the drum use the hammer to give the drum a good whack between each stud(this helps with freeing it from the hub)

Use a thread chaser to clean the two threaded holes that go through the drum

Use 2 bolts that are long enough to press the drum off(evenly tighten them) if they don't move you have a problem

Removing shoes:

Turn the adjuster as far in as possible to release as much tension on the springs as possible

Use diagonal cutters to grip the outside spring and pull it off(you won't cut it, spring steel is hard to cut)

Remove inner spring

Remove the pins in the middle of the shoes by spinning the hat 90 degrees

The shoes will fall off if you aren't holding them so if you are reusing them be careful to not drop them

Removing wheel cylinder:

There are 3 connections in the wheel cylinder(1 line and 2 mounting bolts)

All 3 should be soaked with your lubricator/rust treatment fluid of your choice

Break the line free first but do not remove it

Remove the 2 mounting bolts

Clean all mating surfaces so the sit against each other properly and there is less room for movement.

Getting the new wheel cylinder ready:

Open the bleeder screw

Pour brake fluid into the hole for the brake line and cycle the pistons carefully to get fluid moving inside so bleeding the brakes isn't as hard

Close bleeder screw

Installing new wheel cylinder:

Remove the old cylinder and immediately replace with new one to reduce amount of air you get in the system

Mount the cylinder

Tighten everything down

If using new shoes use old shoes as a guide as to where the pin for the hardware goes

Place shoes using the two spring fasteners

Hook bottom spring onto the shoes

Put ebrake and adjuster pieces back in their place

Place top inner spring in its correct placement

Place outer spring in its place

Measure the inside diameter of the drum where it isn't in contact with the shoes

Adjust the shoes out until they are just under the diameter of the drum

Make sure the shoes are centered so they track properly

Slide drum back on

Using brake spoon adjust the brakes out so they almost touch the drum

Bleeding brakes:

REASSEMBLE EVERYTHING EXCEPT PUTTING THE WHEEL ON

How to bleed brakes:

make sure all bleeders are closed

fill brake fluid resavoir to the full line

have the person in the car depress the pedal slowly and hold at bottom

open the bleeder on chosen wheel then close when flow stops(air or fluid, if air open for a second then close) close bleeder

the person in the car can let pressure off the pedal now

repeat until you get mostly fluid (remember to top off the brake fluid... as in check after 3 or 4 of these cycles)

once you have fluid the pedal can be pumped

3 or 4 slow pumps then hold as before

open bleeder and close when flow stops

repeat

your brakes are bled when no air is present in the fluid coming out of the line and the pedal feels stiff (like your parents vehicles should be)

Once your brakes are bled put your wheel back on. I recommend checking to make sure the lug nuts are tight after driving for a while due to seperating the drum from the hub.

REMEMBER:

Do one side of internals at a time so you can compare setup and make sure you have it right.

If you need new brake lines take the old one to the shop so they can match the nuts and flare.

 
Last edited by a moderator:
Only thing I'd add is which way you turn the adjust screw to tighten/loosen the brake shoes.

I believe when you're adjusting it through the backing plate. You turn it down to tighten, and up to loosen.

The other thing, I'd wire brush and clean all the rust off the mating surfaces. Where the drum mates to the hub, and where the wheel mates to the drum. If there's any rust in there it will cause issues.

Then I usually spray lithium grease on the mounting areas to keep it from rusting so much in the future.

 
Last edited by a moderator:
I know your thread is addressing subaru but I would like to state on other makes and models there can be minor differences with drum removal...like some cars have set screws holding the drum to the hub.. and others have a spindle nut holding the drum on and wheel bearings installed in the drum...

but good thread man!!

 
Last edited by a moderator:
The thread is for newer subaru's for the most part. Also gen 3 vw's. The reason for this is that it is all I have worked on.

 
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