Ok, I'm back. Actually got on quite well with the Sky people but had the usual silly dance around and "just a minute while I speak to my manager" rubbish. Why oh why do we have to have all this silly negotiating every time. They know I'm not going to pay what they've quoted me and I know I'm probably not going to change provider because I'm actually very pleased with the service I get from them, has to be a "sensible" middle ground avoiding all this sillyness doesn't there? Ended up paying just £2.00 more per month for my whole package than last 18 months so well pleased in the end.
So what were we talking about with hand brakes? It was all about how to adjust them wasn't it? And the particular situation we were addressing was how to adjust hand brakes where self adjusters are used. In the main (there can be exceptions like the unusual setup on the Mk1 Panda - I'll come back to that later) you need to back off the handbrake cables until they are quite slack and floppy - ie. Not exerting any pull on the levers at the wheel. This is probably a good thing to do if you are either stripping shoes/pads from the backplates/calipers anyway as it makes working with the cables etc much easier. Then, with the new shoes (if drum brakes) or pads (if discs) installed and everything reassembled (but leave the drums off if you've drums) check that the operating arm of either the caliper or brake shoe is fully returned against it's stop. Here is a picture of a caliper on the Ibiza with it's lever in the fully returned position hard against the stop:
The cable needs to be adjusted - tightened - so that the lever is just pulling away from the stop (you can see a tiny clearance in this picture if you look closely). In practice, because most setups have a single adjusting nut with a balance bar between the two cable to the rear wheels, you'll find the lever on one side will pull away from it's stop just before the other one does. As long as both cables are not seized in anyway you only need to see one caliper lever start to move because friction etc will let one move first. Here's the same caliper with the brake fully applied. You can see the lever doesn't move all that far:
By the way. If you have a VAG vehicle with this caliper it's worth knowing that they are somewhat prone to the handbrake being "lazy" on the return and you'll find it doesn't fully return resulting in a dragging brake. The main agent and pretty much everyone else will want to fit a new caliper, but after a while you'll just end up with the same problem again. I don't know why, maybe the internal return springs weaken? I had exactly this problem on two of the Fabias my boy had and you can fit the external return spring fitted to the Galaxy/Sharan to the lever which completely sorts the problem.
On the drum brakes adjustment is a similar idea. You need to be sure the levers on the shoes are fully returned to their stops. Here's a picture of the 169 Panda trailing rear shoe and it's lever:
Here it is with it's lever fully retracted.
You can see how the wee stop on the lever comes to rest against the shoe. The cables should be loose enough for the shoes to be resting in this position when fitted to the backplate before any adjustments take place.
It needs to be said also that no adjusting of the cable should take place before the self adjusters have fully taken up any free play which is accomplished on most setups by pumping the brake pedal repeatedly - Of course if you're working on drums you need to refit the drums before pumping the pedal!! It may take quite a lot of pumping if the self adjusters have been well backed off. But usually you can feel when the pedal stops improving as you pump it. This pumping up of the self adjusters also needs to take place with disc brakes. Do not touch the hand brake when doing this, it needs to stay on the floor so as not to interfere with the self adjusters action. Once you've achieved a good pedal - and it may be just a little spongy due to new linings, especially where drum brake shoes are concerned, not so much with disc pads - you can go ahead and take the play out of the handbrake cables, but only by as much as is needed to just, and only just, pull the levers away from their stops.
Now, with your foot off the brake pedal, (so, if it's not still up on the stands, chock the wheels or do it on level ground) operate the handbrake a few times, quite firmly, to settle the cable ends and outer sheaths into place. That should see it done but I always take the car for a wee drive and then recheck the clearance at the stops. Often you can take the adjuster up a turn or two due to the cables and everything having settled in. Back when I started in this game on the old BMC Austin, Morris, Wolseley, etc cars It used to be that you were looking for 3 "clicks" on the handbrake ratchet if a handbrake was correctly adjusted, then some of the Fords, I seem to remember, came out with fine tooth ratchets and that measure no longer applied. Nowadays "3 clicks" is not a measure of anything so don't worry if you end up with 6 or even 7 clicks as long as the lever doesn't come up a long way and the handbrake holds well.
Pretty much all the conventional disc brakes I've worked on over recent years work like this but drums do vary as to self adjuster actuation. Most work just as described above, which is to say that pushing the brake pedal with the handbrake released (in the running position, on the floor) allows the adjuster to take up wear in the friction material. Most drum setups are the same, like our wee Pandas/500/etc but there are a very few where its the operating of the handbrake which works the adjuster mechanism - can't actually think of a recent example I've seen though so probably unlikely you'll bump into one. However if you get into the habit of working the lever you should find adjustment will be achieved no matter which type your car has.
I mentioned earlier about the rear brakes on the Mk1 Panda. The shoes look like this:
You can see they look a bit different to our later shoes. Those washers with their big springs are actually the self adjusters. Under the washers there is quite a large diameter hole in the shoe with a thick fibre washer on both sides of the shoe. The spring holds the washers clamped to the shoe. Look at the middle of the assembly and you can see it's hollow. The backplate has a thick peg fixed to it which fits inside that hollow. The outside diameter of the hollow fitting is a little bit larger in diameter than the peg it sits over so there's a wee bit of "slop". It works because when the shoe is moved by the brake cylinder the metal of the shoe slides between the two fibre washers. However when the cylinder stops exerting force the return springs on the shoes will draw the lining away from the drum, just as with any drum brake assembly, but the fibre washers are gripping the shoe more tightly than the force the springs can exert to retract the shoe so it, the shoe that is, can only draw back by the amount of play between the fixed pin in the back plate and the hollow of the spring fitting. The handbrake lever had nothing to do with the self adjuster actuation.
It's drawback was that the fibre washers would become contaminated and cease to grip the shoes with enough force to stop them sliding all the way back so you would end up with a very poor pedal. The handbrake lever assembly was similar to our later setup but the link bar between the two shoes was of fixed length - whereas our later links can alter their length under the influence of the self adjusting screw - This resulted in the handbrake cable having to be tightened periodically as the linings wear. Because it was designed this way you could actually improve the travel on the brake pedal by over tightening the handbrake cable to compensate for the wear on the linings. Unfortunately the pivot on the lever assembly would wear too and they got a bit of a reputation for having a poor handbrake which was quite easily sorted by renewing the lever assembly. In fact you could improve the operation of the handbrake quite considerably by welding some extra metal to the end of the link bar between the shoes thus making it slightly longer which caused the brake lever at the backplate to "cock" itself back somewhat compared to normal and improving the lever ratio on the link bar. I did this on Felicity (the purple/blue Panda in my Avatar picture and my MOT man said, every year, "That's the best Panda handbrake I've ever tested!"
So, hopefully you've followed all that? It's worth me just finishing by saying that if you have taken it all in you will now understand that over tightening the handbrake cables will stop most self adjusting mechanisms from returning to their stops when you take your foot off the pedal so the self adjusters will not work and will be unable to compensate for lining wear.
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