Binding rear brakes, handbrake sticking on

peter999

Today I had a look at the handbrake cable & mechanism, Equaliser Lever & the Adjuster, under the car.

My road is on slight hill.
I operated & released handbrake.

Car did not roll forward, even though handbrake released.

Looked under car, the Equaliser Lever, which connects to the rear brakes, was still in same position. (It seems quite stiff, I've lubricated it.)

As soon as I moved this Lever a little, the car started to roll forward.

Not sure how this Equaliiser Lever works, as it seems to pull cable on Near Side & push a rod on Off Side.

I don't know that this Lever not moving much means much, as as soon as cable is released, I think you only need a fraction movement of shoes in drums to release rear brakes.


My handbrake is pulling high at 10 notches. With handbrake released cable seems a bit slack adjacent to adjuster, meaning the cable springs have a lot to pull back.

I've adjusted the handbrake to 4 notches & lubricated the mechanism under the car.
.

peter999

I'm going to check inside the drums tomorrow.

I think the Springs inside the Drums are the main thing (force) which pull Brake Shoes away from Brake Drum.

Is that correct ??

gilbert_and_sullivan

peter999 wrote: »

I'm going to check inside the drums tomorrow.

I think the Springs inside the Drums are the main thing (force) which pull Brake Shoes away from Brake Drum.

Is that correct ??

There's usually a spring on the handbrake equaliser on most cars but whether Micra has this i couldn't say.

Lubricating the brakes properly is a regular, indeed annual, thing, handbrake cables, pivots and linkages and all other moving parts both inside drums and outside..eg caliper sliders.

Neglect is the usual cause of sticking binding etc, once seized its too late to just lubricate, its then time for full dismantle clean reassemble.

peter999

gilbert_and_sullivan wrote: »

There's usually a spring on the handbrake equaliser on most cars but whether Micra has this i couldn't say.

Lubricating the brakes properly is a regular, indeed annual, thing, handbrake cables, pivots and linkages and all other moving parts both inside drums and outside..eg caliper sliders.

Neglect is the usual cause of sticking binding etc, once seized its too late to just lubricate, its then time for full dismantle clean reassemble.

I've stripped down both brake drums.

Nothing looked wrong or looked like it was sticking in either of them.

But I still have same problem with both wheels binding, so it must be the cables & equaliser lever mechanism.

I can see it & test it.

With handbrake operated then released, the equaliser stays in position & doesn't return, which keeps handbrake cable tensioned on both sides, locking both drums/wheels.

As soon as I push back the equaliser a little, which releases handbrake cable on both sides, wheels are freed.

I also tested this with wheel hub off, before & after I stripped down brake shoes. Operating & releasing handbrake, I could pull through brake cable at hub, to pull in brake shoes.

peter999

What I have done has improved things, but not sure if it's good enough to pass MOT.

Does anyone know if this handbrake & wheel (binding) MOT test is done by hand or on rolling road ??

My rear wheels release as soon as car is driven.

But if MOT test is done by hand, you would feel wheels are binding after operating & releasing handbrake.

Don't think this may be seen if it's done on rolling road.


Anyone know, does MOT test do by hand or rolling road ??

peter999

Looksguywalker

Put my Astra in for MOT last Monday and brakes were tested on a rolling road.

peter999

Looksguywalker wrote: »

Put my Astra in for MOT last Monday and brakes were tested on a rolling road.

I know they test brake on each wheel on rolling road.
The handbrake test, I assume on rolling road.

I know they test each wheel for its rotation & bearing by hand.

MOT tester could have felt wheels binding during this test, after handbrake had been operated.

Thinking about it, I'm not sure if he saw/felt wheels binding during handbrake test or when checking the wheels by hand.

gilbert_and_sullivan

peter999 wrote: »

I've stripped down both brake drums.

Nothing looked wrong or looked like it was sticking in either of them.

But I still have same problem with both wheels binding, so it must be the cables & equaliser lever mechanism.

I can see it & test it.

With handbrake operated then released, the equaliser stays in position & doesn't return, which keeps handbrake cable tensioned on both sides, locking both drums/wheels.

As soon as I push back the equaliser a little, which releases handbrake cable on both sides, wheels are freed.

I also tested this with wheel hub off, before & after I stripped down brake shoes. Operating & releasing handbrake, I could pull through brake cable at hub, to pull in brake shoes.

Sounds like the cable is sticking then, is it easy to disconnect the cable at the hub end?, if so you should be able to work the cable back and forth a fair amount, lubricating it at each end when its as far out of the outer cable as possible, repeat several times and you should have a fully lubed cable.

I tend to lube each end of brake cable quite regularly, that way the lube can be workig its way through, and helps keep out salty water.

Easier in Morris Minor days when greasing points were fitted half way down the cable.;)

Is everything else free and lubed inside the drums?, are slave cylinder pistons free moving?, is the self adjuster (presumably) free?

[Deleted User]

peter999 wrote: »

Anyone know, does MOT test do by hand or rolling road ??

Both.

Brake efficiency is tested on the rolling road, and the car is jacked up to inspect the wheels and tyres, which of course requires the wheels to be rotated.

If the wheels cannot be rotated by hand, the car will be failed.

Don't mess around. Fix them properly.

It doesn't pay to cut corners, where brakes are concerned.

peter999

I took car into garage, they found that the Equaliser Quadrant mechanism which pulls both rear brake cables was seized up.

To be honest, it hasn't been lubricated for years.


They lubricated & freed-up by moving backwards & forwards.

Handbrake now working ok, with rear brake shoes releasing when handbrake is released.

peter999