Guaranteed A1100% Hand Brake Adjustment..Please!

[bonnietiler]

Ok...I have the new LSD fitted and I've changed the brake cylinders and bled everything but ,,,I cant get anything resembling a decent handbrake..it did work before..
Can anybody give me a simple walkthrough I suspect I'm making my mistake at the compensator.. I have cleaned the shoes and the drums the cable is not that old and adjusted underneath as well as at the back.
Any help much appreciated.
Bonnietiler

[dursleyman]

Back off all the adjusters to begin with so everything is slack. Now start with making sure the brake shoes are adjusted properly, you will most likely have to do it manually because you cannot rely on the self adjusters. They need to be just on the point of almost dragging. Make sure all the linkages are free including that pivot on that central compensator. It will be approximately vertical when everything is finished. Make sure your cable to the handbrake lever is free and lubricated. Now you can start to adjust the cables at each brake lever still keeping the compensator central. They do not need to be tight, my cables are quite slack and floppy with the handbrake off. Once all that is done you can still take up excess slack at the handbrake lever in the tunnel.
Is it working now?

[Howard722]

You can only get a good handbrake if the self adjusters are in good condition and working properly!
Even if you can hear them ratcheting up, the pressure caused by the handbrake being applied can force them to `de-ratchet`if they are worn - and you lose the handrake. You can only check this `wear` with a high mag. magnifying glass!-all may look&sound OK to a casual inspection but those teeth take some strain and they are very small and they do wear out.

[Hasbeen]

15 years ago now I rebuilt the brakes on my 7. To get the auto adjusters to work I polished with a wire wheel on the bench grinder, every bit of the shoes & the adjusters anywhere where they touched each other, then lubricated all moving touching parts with a puff of graphite powder. They still work fine to this day after 75,000 kilometres.

A kiwi member we have not heard from for some years rebuilt his brakes, & had the self adjusters locking his brakes on every time he applied them. I suggested he polish the touching bits, which he did. While doing this he found a bit of weld spatter on one shoe was causing his problem. With it ground off, & the rest of the contacting parts polished & lubricated they worked perfectly.


Obviously he had changed the position of the shoes, so the part of this shoe with the weld spatter was now in contact with the adjusters. That shoe must have previously been in a place where the splatter was not touching anything.

Give consideration to the possibility that you have changed the location of the shoes in your rebuild, & this is causing you a new problem, just in case lightening does strike twice in the same place.

Hasbeen

[FI Spyder]

Like Hasbeen I've cleaning all parts. Any metal to metal contact, I put a thin film of brake grease (which is a high temp thick paste design for this) on. Brake dust will collect on this but that's OK. Assuming they are assembled correctly, manual adjust the brakes from the backside to get them close to where they should be (as per manual). The auto adjusters will take care of the rest (fine tuning). You can go back and forth a few times jamming on the brakes to get the autos to do their job. When the brake shoes are set correctly, the emergency cables can be adjusted as per manual. I had previously taken the moving parts of the e brake apart and cleaned them of rust and other crap and assembled them with brake grease which ensured that they are free to move as designed with out any hand brake force being lost in trying to over come friction in the system.

[saabfast]

My handbrake was pretty poor, then just started jamming without latching on properly but I couldn't find the fault. Then I replaced the cable, stripped and greased the compensator and, like Hasbeen, I stripped all the brakes out and cleaned it all up (not to the extent of polishing though), then reassembled with graphite power. Its now as good as any other car.

[dursleyman]

That seems to be the answer, it ALL needs to be in good condition. If in doubt then clean/lubricate/replace as appropriate and you can get it back. Once you assume or accept anything not 100% then you are on a loser.

[busheytrader]

Like Hasbeen I cleaned all the handbrake's moving parts in the rear drums back to clean metal with a wire brush attachment in an angle grinder. Lubricating or greasing them afterwards attracts brake dust which gums up the mechanism so I just use graphite powder. I reckon it takes about 2 years before they need cleaning again. One of those electroplating kits would probably stop the surface rust reappearing. New brake adjusters are available for £90.00 http://www.rimmerbros.co.uk/Item--i-AAU8994.


Other problems I've found are the rubber bush disintegrating within the central compensator and wear on the back plates where the handbrake levers pivot against it. The backplate wear was removed with a small amount of weld filed back to the original profile.

[Hasbeen]

Incidentally I have a pair of Stag 76 hand brake lever extenders. These give the hand brake more leverage on the lever, increasing it's locking power quite a bit.

How about a photo, or a drawing of them Stag 76.

Hasbeen

[Stag76]

[busheytrader]

Like Hasbeen I cleaned all the handbrake's moving parts in the rear drums back to clean metal with a wire brush attachment in an angle grinder. Lubricating or greasing them afterwards attracts brake dust which gums up the mechanism so I just use graphite powder. I reckon it takes about 2 years before they need cleaning again. One of those electroplating kits would probably stop the surface rust reappearing. New brake adjusters are available for £90.00 http://www.rimmerbros.co.uk/Item--i-AAU8994.


Other problems I've found are the rubber bush disintegrating within the central compensator and wear on the back plates where the handbrake levers pivot against it. The backplate wear was removed with a small amount of weld filed back to the original profile.

Embarrassingly I found out the hard way as to why my handbrake cable has always been at the limit of its adjustment. I thought I'd share it in case anyone's having the same problem.

Ever since I bought my Wedge back in 1986, the handbrake just passed the mot and before each test I had to clean up the handbrake mechanism, including the self adjusting ratchet plates on the brake shoes, replacing them exactly as I found them. I did one side at a time referring to photos I'd taken before dismantling. My Haynes manual diagram was none too clear, so had to refer to the photos. Unfortunately, before my ownership, the self adjusting mechanism had been put back incorrectly.........

It should look like this (courtesy of a Jensen Healey forum). https://photobucket.com/gallery/user/Ni ... cGVn/?ref=

It had been assembled like this. https://www.google.co.uk/search?q=tr7+h ... QJSPbRceXM

The larger of the plates had been fitted upside down. Subsequently there was less metal for the handbrake mechanism to push against and all the cable adjustment was needed to work the handbrake. The ratchet teeth were compromised and prone to wear out prematurely as they weren't positioned as intended. I returned mine to the correct position but the ratchets on one set wouldn't work correctly. I managed to rescue them by running a fine hacksaw blade gently between all the teeth on both sides. Now there's plenty of adjustment and the handbrake works fine. If the teeth don't engage properly, the handbrake won't work properly.

[Hasbeen]

Since this thread I discovered the self adjusters at least on mine, work better if you apply the foot brake while reversing at a little pace.

I was reading an old Renault drivers hand book which advised braking while reversing was required to make their adjusters work properly. I don't know if this is a requirement with ours, but I tried it on my 7, & they they do adjust closer if that advice is followed.

Hasbeen

[Cobber]

Since this thread I discovered the self adjusters at least on mine, work better if you apply the foot brake whine reversing at a little pace.

I was reading an old Renault drivers hand book which advised braking while reversing was required to make their adjusters work properly. I don't know if this is a requirement with ours, but I tried it on my 7, & they they do adjust closer if that advice is followed.

Hasbeen

I've found this to be the case with most self adjusters

[FI Spyder]

I always thought that is how they are designed to work.

[busheytrader]

My rudimentary understanding after finally correcting the self adjusting mechanism is....

The self adjusters hold the brake shoes' resting point from the brake drums. With the handbrake off and the shoes pressed against the drum by the footbrake, the self adjuster ratchets up a tooth to compensate for lining wear if required. Once the footbrake is released, the brake shoes should return to about the same distance from the drum as before.

Wear in the brake shoes is compensated by the hydraulic brake cylinders moving to an advanced resting position, set by the self adjusters. The self adjusters ratcheting up a tooth keeps the handbrake lever in the same position as before for normal operation. I imagine using the footbrake in reverse would be enough to rotate the shoes from the self adjusters, just enough, to advance them a tooth earlier than would be done in normal forward motion.

I guess the shorter version of my earlier post would be.........don't assume all the photos over the Internet show the self adjuster plates in the correct position. The lightest working of the teeth with a fine hacksaw blade may reinstate their effectiveness if worn.