Electric Hand brake

[WhiteD3]

So, how does it work?

Mechanically?
Electrically?
What is it's normal (unpowered) state? On or off, or is this irrelevant?

Done 24,000k with no issues at all but I still feel uncomfortable leaving it on on a hill with the engine running:o



Cheers.

[Blknight.aus]

If Id designed it..

it would be an electric over mechanical setup like trailer brakes but in reverse IE electrically pulled off mechanical spring applied brake.

so in theory if you were sitting with the parkbrake on then thered be no volts at the brake actuator.

But you could also do it with a pulse to change state setup by using an over center solenoid so one pulse of power applies the brakes and the next releases them.

[CaverD3]

Funny you should ask that.

Discussion being had on disco3:

DISCO3.CO.UK - View topic - STOPPING ON STEEP SLOPE (http://www.disco3.co.uk/forum/viewtopic.php?p=287512#287512)

Looks like there may be a technique for stoppig on a hill.:)

[Blknight.aus]

that thread doesnt appear to be talking about the park brake but the automatic brake lock.

If you brake to a halt its essentially a non return solenoid that stops the brake fluid from returning through the master cylinder. Very Cool for hill starting an auto

[p38arover]

that thread doesnt appear to be talking about the park brake but the automatic brake lock.

If you brake to a halt its essentially a non return solenoid that stops the brake fluid from returning through the master cylinder. Very Cool for hill starting an auto

My 1955 Jaguar Mk VIIM had one of those. Called anti-creep or hill-hold.

[Jamo]

It electrically operates, via cable, a set of drum brakes at the rear wheels.

If you are doing over a certain speed it then activates the rear disks and operates as an emergency brake.

If you get mud in it it makes an horrendous shrieking noise that causes all heads within about a 500m radius to turn and look! You then need it cleaned out (before it implodes)!

[Graeme]

If you are doing over a certain speed it then activates the rear disks and operates as an emergency brake.

The emergency function operates all 4 discs at maximum, but if the hydraulic system has failed then the drum brakes are applied even at high speed.

Just imagine having a rego check done by a mechanic who doesn't know and he/she pulls the switch to test the hand-brake.....

[WhiteD3]

It electrically operates, via cable, a set of drum brakes at the rear wheels.

If you are doing over a certain speed it then activates the rear disks and operates as an emergency brake.

If you get mud in it it makes an horrendous shrieking noise that causes all heads within about a 500m radius to turn and look! You then need it cleaned out (before it implodes)!


Thanks Jamo. Some clarification though!

There's the button/lever, the cable, the drum brake.
What and where exactly is the electrical mechanism?
Does the drum have an electric mechanism in it, triggered mechanically via the level in the cab?

I assume this is the case as the manual method involves unbolting the lever and manually working the mechanism.

What is the "powered" position of the drum actuator, brake engaged or released?
And are there implications for this when the battery is flat?

This drum brake; is it on both rear wheels or only one?

Oh, and I've had that shrieking noise! Picked up a rock or some such on a track but it went away after a few K's.
http://www.youtube.com/watch?v=XDLl6C9-SmI&eurl=http://www.aulro.com/afvb/queensland-reports/51634-mt-mee-16-2-08-a.html
Cheers.

[Bigbjorn]

My 1955 Jaguar Mk VIIM had one of those. Called anti-creep or hill-hold.

Studebaker and others had a hill holder in 1927

[p38arover]

Studebaker and others had a hill holder in 1927

It's all old tech come back to haunt us! :D

Soon the Japanese will add it to their vehicles. :angel:

[CaverD3]

Oh, and I've had that shrieking noise! Picked up a rock or some such on a track but it went away after a few K's.
Cheers.

Different noise with handbrake. Yours was a rock in the disk cover.
When putting the handbrake on it can make a hideous shreik as opposed to your muffled whimper/:o

disco3 poll gives 30% who have had at least one occurance.

[Jamo]

In response to your detail questions: Dunno! That's outside my current level of expertise!;)

And, like Caver said, when you get the park-brake-needs-cleaning/adjustment-squeal, you'll know it!:eek:

[300+]

Thanks Jamo. Some clarification though!

There's the button/lever, the cable, the drum brake.
What and where exactly is the electrical mechanism?
Does the drum have an electric mechanism in it, triggered mechanically via the level in the cab?

I assume this is the case as the manual method involves unbolting the lever and manually working the mechanism.

What is the "powered" position of the drum actuator, brake engaged or released?
And are there implications for this when the battery is flat?

This drum brake; is it on both rear wheels or only one?


There is a conventional mechanical/cable operated drum in the centre of each rear wheel The other end of the cable is near the hand brake lever. In the same place there is the motor to pull it against some sort of ratchet/one way system to hold it without power or assistance.

So the unpowered situation is a conventional mechanical handbrake with no way to release it (as that is a powered event). Which is why there is a section in the manual to show how you pull off the cover beside the lever and reach in with some tool in the tool kit and release it. This is a one time operation which disconnects the cable from the activator and requires "dealer servicing" to fix.

If the brake engages I would have as much faith in it holding as any other mechanical system. In fact, it is likely better and it will increase the tension if it detects creep. This is again a powered operation, but I would expect it to work with the engine off, keys out, doors locked, etc.

Cheers, Steve

[Graeme]

There are 2 cables - 1 from each wheel to a gbox that pulls the 2 cables together using a worm-type drive. The emergency release cable is a 3rd cable that separates the 2 that are linked together in the worm-drive box. The 1st application of the EPB after the emergency cable has been used causes the 2 wheel cables to be reconnected, but does not apply the EPB, so that the EPB is functional again. No dealer intervention is necessary, according to the WSM

[sclarke]

It's all old tech come back to haunt us! :D

Soon the Japanese will add it to their vehicles. :angel:

They have.... Subaru have it

[PCH]

Here's a picture of the motor assembly on cut away creations. The module sits above the rear diff.



http://www.cutawaycreations.com/IMAGES/car1/images/image27.jpg

[Forest]

No idea how it works, but I broke the switch:eek: for goodness sake. Broke it yesterday (no idea how that happened) and fixed to day. Good to know it wasn't anything I did!!!

[WA Darryl]

Quote:
Originally Posted by Jamo


If you get mud in it it makes an horrendous shrieking noise that causes all heads within about a 500m radius to turn and look! You then need it cleaned out (before it implodes)!

Hey All,
I have got the shriek you have discussed, after a trip to the Pilbara. Has been there for over a week now and doesn't seem like it will self clear. None of the threads so far have mentioned what to do about it. Do I attack the hubs with the hose, or is it more like a back to Land Rover job? If so maybe warranty? surely My "Most Awarded 4WD in the World" cand handle a bit of gravel.;)

[mcrover]

It's all old tech come back to haunt us! :D

Soon the Japanese will add it to their vehicles. :angel:

Subaru were doing it in the 80's, my brumby had "Hill hold" where if you stopped on a hill with your foot on the brakes and the clutch then you could release the brake pedal and the car would hold until the clutch was released to a preset position which was adjustable under the bonnet.

It was a fantastic trinket that took ages for me to get my head around but once I did I wished Id had it on all my cars.

[Bushwanderer]

My partner's Subaru Sports Wagon (1990?) had it, so the Japanese have already been there. ;)

[BigJon]

Quote:
Originally Posted by Jamo


If you get mud in it it makes an horrendous shrieking noise that causes all heads within about a 500m radius to turn and look! You then need it cleaned out (before it implodes)!

Hey All,
I have got the shriek you have discussed, after a trip to the Pilbara. Has been there for over a week now and doesn't seem like it will self clear. None of the threads so far have mentioned what to do about it. Do I attack the hubs with the hose, or is it more like a back to Land Rover job? If so maybe warranty? surely My "Most Awarded 4WD in the World" cand handle a bit of gravel.;)

Unless you are pretty handy get your mechanic to do it. It involves removal of the brake calipers and discs.

In my experience (ex Warranty Admin) it isn't warrantable.

[BigJon]

They have.... Subaru have it

Given that Ron has had at least two Foresters, I think his comment was tongue in cheek...

[scarry]

seems bloody hi tech just for a handbrake.....give me the d2 leaver any day...its only something else to fail in the mud,sand,water etc that these vehicles are made to travel through:(

ummm.......is that kiss again:D:D

cheers

[TDV6]

I had a flat battery in Katherin NT last year, dam near got a hernia trying to release the park break, was not able to, I think that you have to have 12v use the emergency release but please correct me. Car had new battery fitted in Darwin.

[Graeme]

I had a flat battery in Katherin NT last year, dam near got a hernia trying to release the park break, was not able to, I think that you have to have 12v use the emergency release but please correct me. Car had new battery fitted in Darwin.
Its strictly a mechanical release requiring 45LB force, designed for the jack handle to be inserted into the hook and a screwdriver into the jack handle. One of its main functions is so that the handbrake can be released when the battery is disconnected or below 7.5v when trying to release the EPB.