Although the rear brakes adjust themselves, they don't always adjust properly.
As the brake shoes wear down, the auto adjusters move the brake
shoes closer to the drum so the foot brake travel isn't increased.
There is a self adjusting mechanism at the base of the handbrake lever too but this too can have issues. When the brake shoes are worn or the cables stretch it can be outside the adjusting range.
This will create slack on the handbrake cables to both rear brakes.
The handbrake lever will have to be moved further before it moves
the brakes and even further before they start to touch the brake drums.
As the brake shoes wear down, the resting position of the lever will be higher
and higher. Eventually the ideal resting position for the handbrake will fall in
between two clicks of the ratchet on the handle as you pull it. The lower position
won't be enough and the brakes won't stop the car creeping away, the higher
position will take some strength to pull to and can slowly stretch the cables.
At this point you can either fit new brake shoes or adjust the handbrake.
Adjusting The Brakes
Thanks to Chris Ryu for the information
First we need to ensure the brake shoes are wearing and braking evenly.
Jack the car up and remove back wheels. Undo the tiny torx screw (careful not to round it off!),
remove the drum and clean to avoid harmful dust entering the air. You should see a small gear.
turn it using a flat screwdriver until the pads are far from the outside. Replace the drum
(don't put the screw in) and turn until you can see the gear through one of the wheel bolt holes.
Using the flat screw driver adjust the gear the other way until it gets to the point where you
can no longer turn the drum by hand. Back the gear off another 4 clicks and put the screw
back into the drum. Replace the wheel and complete the same on the other side.
Adjusting The Handbrake Lever Position Thanks to Tolsen for the info
Adjusting the drum pistons as shown above will alter the handbrake position.
The handbrake itself is self adjusting from the lever base.
If you find the lever goes too high you either need to adjust the drums or fit new brake shoes.
If neither help, you can attempted to apply and release the handbrake several times in case the
automatic adjuster has seized or the handbrake cables could have stretched and need replacing.
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