1980s Girling caliper with integral handbrake problems

[Harry Bloomfield]

That's a generic image, I think. Mine don't QUITE look like that. (And the car isn't worth the cost of a pair of them at that price anyway)!

I had (I think) a SAAB and then later Granada with that sort of arrangement and I grew to hate the system. The main design issue seemed to be where the handbrake lever arm, entered the caliper - The seals perished and the rotating arm would rust and seize. It was an annual pre-MOT job, to lubricate and free up those arms.

On cars generally, how far up the actual cabin lever comes up (number of clicks) can greatly affect the amount of effort you can apply to braking the wheels. The fewer the clicks, the more leverage you can apply with your left arm. My present car has combined disk and drum at the rear - It's handbrake is superb and reliable at two clicks. It wasn't always thus - I bought it with it at 7 clicks and barely passing the MOT.

The handbrake drums would develop rust on the internal surface, through lack of use of the handbrake when in motion and as the system then became so ineffective, much more than normal effort was needed to apply the handbrake - that would result in the weak design of compensator stretching and even more clicks needed, until they ran out of adjustment.

The simple fix I arrived at was to reinforce the compensator, so it could no longer stretch, adjust the system to two clicks and use the bl**dy handbrake regularly, to prevent the drum internal surface rusting.

 

[Avocet]

Yes, that's exactly what happens with mine! I've taken to packing the area between the arm and the body of the casting with waterproof grease to try and stop the water going up that shaft and seizing it. They are indeed, the work of the devil, but it has discs on both ends and this is the lightest way of doing a handbrake with disc brakes. I just have to live with it.

The lever is an odd one. Depending on the geometry of the lever, you can get more force down the cable for a given applied force at the tip of the handle, once the shorter arm on the bottom has gone "over centre" as it were. However, the price you pay for this, is longer travel and you soon get to the point of diminishing returns. Like you, I always felt that the fewer clicks, the better, but was surprised when I was struggling with the (drum) rear brakes on my old Freelander and in desperation, looked at the Haynes manual which suggested 4-5 clicks. To my surprise, backing the cable off and letting the lever travel a bit further from the 2-3 clicks that I had it, produced a very noticeable improvement in performance!

 

[Avocet]

Have you got a good picture of the caliper?.

My MK2 Golf was on Girlings iirc and the only real fix was to fit MK4 calipers on the back which were practically a straight swap.

Piccies from last night.

 

[Avocet]

Also, another update from last night guys.

I discovered two things, on removing the calipers:

1. The pads are showing a burnished patch but they're still not fully bedded-in. I thought they were, but actually, when I wipe the brake dust of the surface and look very closely, I can see that the patch hasn't covered the whole surface area of the pad yet. In particular, the outermost area is not yet burnished. Maybe about 1/4" from the edge of the pad, all round. Obviously, any braking effect applied closer to the outermost perimeter of the disc, will have a proportionately higher stopping effect, so that last 1/4" might prove significant. Looks like I need another few hundred miles on it yet.

2. The "bad" caliper that wasn't ratcheting out when the handbrake lever was repeatedly actuated, was still "bad". However I put both calipers on the bench and went in for my tea, then forgot which one the bad one was, so I put them both back in the vice to find out. This time, the "bad" one, did make more of an effort to move. I then spent a while ratcheting it out about 10 times and winding it back in again - at the end of which, it seemed to be working repeatably and reliably. They now both ratchet themselves out nicely when the lever is moved through its full range of travel. I'm putting this down to a bit of "newness"!

My plan, therefore, is to stick them back on the car and run it for some more miles to see if things improve.

 

[DIYspanner]

Surely the calipers should both have been inspected and working perfectly before BiggRed returned them to you?

 

[Avocet]

One might have hoped so, but...

To be honest, I know I didn't opt to pay the extra for their super high-temperature, glossy, lime green fluorescent paint job (it really isn't that kind of car!), but one of them had rust breaking through the silver paint that they had applied to it when I took it out of its box! It looked like they'd given the castings a cursory sand blast and then squirted an aerosol of silver paint at them.

To be fair, when I spoke to them today, they seemed genuinely concerned and were happy to get a courier to pick them up from me at their cost, but I think (I'll check again this evening) that both pistons are now behaving as they should.

 

[Gasguru]

I wonder how much is actually refurbed?
If the diagrams I've found on the web are accurate the self adjusting mechanism appears to comprise a thread with a high helix angle...and the slightest wear will result in seizing..just like a conventional basin tap.

 

[Harry Bloomfield]

If the diagrams I've found on the web are accurate the self adjusting mechanism appears to comprise a thread with a high helix angle...and the slightest wear will result in seizing..just like a conventional basin tap.

Yep, that's how they work. They usually need a special adaptor in order to be able to wind them back, when you change the pads. If they are not free to turn, then the handbrake will have issues.

 

[Old Salt]

Not sure if this has been covered yet but once you get them refitted you can check the adjustment has been even on both sides. Jack the car up and whilst using axle stands apply the handbrake 1 click at a time checking if the rear wheels bind. You may find one binds much earlier than the other.

 

[DIYspanner]

Not sure if this has been covered yet but once you get them refitted you can check the adjustment has been even on both sides. Jack the car up and whilst using axle stands apply the handbrake 1 click at a time checking if the rear wheels bind. You may find one binds much earlier than the other.

Indeed!

The Picanto handbrake cable I mentioned earlier still causes the wheel to catch before the other side on the adjuster so I gave the handbrake lever plenty travel to keep it from seizing. When mot'd back in December the handbrake was well balanced so I'm content.

 

[DIYspanner]

Just a thought. If the calipers do prove to be a bother, TRW manufacture calipers.

https://www.trwaftermarket.com/en/catalogue/

 

[Mottie]

One other thing but you may already be aware and looking at the calliper you probably are but on wind-back pistons with cut outs in them, you have to make sure that the pin on the back of the pad (if it has one) is sitting in the cut outs otherwise the piston will not be pushing squarely on the pad and will give you a bad handbrake and/or a partially worn pad.

Oh, and make sure the calliper sliders are free.