5 replies to this topic

[Jordan Loughlin]

Hi Guys,

My Mini City E, 1988, 998cc, has been sitting in the garage now since June 2010 whilst I have been 'doing it up' so to speak. I am nearly finished (thank god) but since about January this year, the brakes have been seized, not fully, and I have tried driving it up and down the drive to loosen them off. Do I need to take the drums off and replace anything? Or is there a simple way to adjust them?

Any help much appreciated.

Jordan

[RawlinsGTR]

The rear brakes are drum brakes, that can be adjusted using the "brake adjuster screw".

You will see a square screw head that pokes out the back of the drum brake plate (you'll need to take the wheel off).

Screwing this adjuster tighter pushes two chips into the brake shoes, forcing the brake shoes outwards and onto the inside of the actual drum, thus tightening the whole system.

Unscrewing this adjuster lets the two chips inwards, letting the brake shoes come inwards, thus becoming less tight on the inside of the actual drum, thus loosening the whole system.

However, you may find that screwing this adjuster is incredibly hard, and that it won't move. This means that the brake adjuster screw is siezed in its thread. Trying constantly to undo it will result in the rounding of the head, and you will have to replace the whole back plate.

What I suggest doing is seeing if you can loosen/tighten this adjuster screw with a normal spanner first. Then, if you're unable to do that, buy a correctly sized dedicated brake adjuster spanner (the head on the brake adjuster screw is not uniform socket size, and is actually properly square), and try with that, along with some proper penetrating fluid. If that fails, use a lot of heat to try and loosen the screw, whilst unscrewing it with the dedicated brake adjuster spanner. Once you have fully removed the brake adjuster screw, replace it with a new one that isn't corroded.

Remember, to fully remove the brake adjuster screw, you'll need to take the drum off, as the screw will only fully come out from the brake shoe side of the back plate, and not the side from which you screw it.

Then use a Haynes Manual to read up how to properly adjust the rear drum brakes so that the brake pedal does not depress too far, and that the handbrake works to its best ability.

So in a more concise manner:
1. Remove the brake drum from the hub.
2. Remove the brake adjuster screw. (You will need to remove the brake shoes too - memorize how they went on first, or you may put them back on the wrong way round) If it's seized, use the techniques I spoke about and replace it with a new one.
3. Adjust the rear brakes as told in the Haynes Manual.

Hopefully this helps.

Simon.

[AVV IT]

It depends on what has actually seized. In a laid up car it is often just the handbrake mechanism that is the problem, which can often be freed off with some gentle persuasion/taps from a hammer on the back of lever that passes through the backplate on each drum (at least this should free it off enough to get the drum off to inspect it further.)

To be on the safe side, I would recommend a thorough inspection and overhaul of any drum brake that has seized, and if the car has been off the road for 18 months or so, then a full brake fluid change would be advisable anyway. The Haynes manual describes how to remove, inspect, overhaul and refit the various components fairly well. Although for the price of a new wheel cylinder (£7 - £8 each), I wouldn't bother with replacing the seals as described in Haynes and would just replace with a new cylinder instead (in fact I'm not even sure if you can buy seals/overhaul kits any more these days?? )

[RawlinsGTR]

Now that's what I forgot to add. What I also should have said was "of course, it might not be this, I'd check the other parts, but the main bit I know about is the bit that I've just described. However, the fact that you are able to drive it as you've described makes me think that something's binding".

[Jordan Loughlin]

Thanks guys, yes it is binding, been out working on the car in the past hour getting it all sorted for an MOT etc. Too cold now to do all that, but I will try and get back to you to let you know how it went. Very grateful for your suggestions....

Jordan

[bmcecosse]

You will need to get the drums off - and free up the handbrake levers and check the quadrants are moving easily. Then check the brake pistons - very likely seized - if they don't free easily fit new cylinders, and yes - get the adjusters moving easily and slap grease all over them........