Handbrake - movement at the wheel

[HarryM1BYT]

The question is a regular one - why is the rear wheel still able to move slightly, when the handbrake is fully applied. The movement is often accompanied by a creaking noise....

PAB had his car up here a few days ago, changing the rear disks, so I did a bit of investigation to determine the cause of the shoes moving. It is the shoes moving, if anyone was in any doubt.

A the top, is the adjuster to take up play as the shoes wear. At the bottom is a bracket between the two lower shoe faces, which is fixed to the back plate. That lower bracket is the one which moves and allows the wheel to turn a few degrees.

Its absolutely nothing to worry about, just a 'feature' of the car.

[klarzy]

Originally Posted by HarryM1BYT

The question is a regular one - why is the rear wheel still able to move slightly, when the handbrake is fully applied. The movement is often accompanied by a creaking noise....

PAB had his car up here a few days ago, changing the rear disks, so I did a bit of investigation to determine the cause of the shoes moving. It is the shoes moving, if anyone was in any doubt.

A the top, is the adjuster to take up play as the shoes wear. At the bottom is a bracket between the two lower shoe faces, which is fixed to the back plate. That lower bracket is the one which moves and allows the wheel to turn a few degrees.

Its absolutely nothing to worry about, just a 'feature' of the car.

Plain old mechanical backlash Harry.

[FezzyFox]

My zt has always done this. Rolls forward about an inch when i pull the handbrake and let off the foot brake. It passed the MOT with no complaints too, and i did mention the 'feature' to the tester at the time

[Beena wild]

Just like in the oul' american cop shows.....

Column stick , slam on , bouncy suspension (really bouncy) and then obligatory jump forward. Priceless

[Number 6]

Originally Posted by klarzy

Plain old mechanical backlash Harry.

Is there any way to "remove" the mechanical back lash??

[FezzyFox]

Originally Posted by Number 6

Is there any way to "remove" the mechanical back lash??

Replacing the shoes i'd imagine. That way there is loads of friction material left & no 'slack' to be taken up by the adjuster.

[Number 6]

Originally Posted by FezzyFox

Replacing the shoes i'd imagine. That way there is loads of friction material left & no 'slack' to be taken up by the adjuster.

I have replaced the shoes and the disc,s and adjusted up as per instructions but still loads of "Backlash"

[HarryM1BYT]

Originally Posted by Number 6

Is there any way to "remove" the mechanical back lash??

Changing the shoes will not make any difference at all. The lower brackets are able to move on the back plate and that is what needs to be addressed, but I didn't explore that at all.

With the drum off, you can rotate the shoes back and forth and see the adjuster plus that lower bracket turn.

[klarzy]

Originally Posted by Number 6

Is there any way to "remove" the mechanical back lash??

no, the whole assembly floats on the 2 spring pins, the lower lever and the upper expansion unit are not fixed. I had to replace one of my sprung pins today as the spring had corroded and the pin fell and bent..

Most drum brake assemblies work off of a hydraulic expansion piston and this is fixed and does not allow the assembly to float whereas the rover lever type does.

One thing I have learned is that it is recommended to lightly apply the handbrake while rolling every now and again to clear surface corrosion, I will no longer do this as if you apply slightly too much pressure you can tear the shoes off of the pins and stretch the cable or damage the hole in the back plate if you do with the current configuration..

I think it is better to have the handbrake shoes just rubbing all of the time with the handbrake off...

[T-Cut]

Originally Posted by HarryM1BYT

The lower brackets are able to move on the back plate and that is what needs to be addressed

There seems to be no mechanical advangage in having the bracket slide (sideways presumably), so why does this feature exist? I always assumed the lower bracket was firmly riveted to the backplate, but seems not. To rotate the tyre by a degree or two (or whatever it is) wouldn't need significant slop in the lower bracket, so one wonders whether it's an assembly issue rather than a design feature. These aren't all that rare (the leaky Mk2 front indicator for example). If the bracket really does need to be solid, maybe the rivets could be given a nother go or maybe the bracket could be spot welded to the plate.

TC