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Discussion Starter #1
I have just fitted new rear pads to my QV, and before hand the rear brakes seemed to be giving uneven effort on each wheel.

Now after refitting the new pads, checking everything is moving freely they still seem to be giving uneven effort.
I have had the same problem with a Fiat coupe and I never did get to the bottom of the problem on that either.

I am also told that if the problem is the load proportion valve, I would get poor effort on both rear brakes, but it would still be fairly even between the 2 brakes.

The handbrake seems to work ok but is not brilliant, its just I have an MOT in the not too distant future and I am worried about this. The discs are hardly worn either..

Does anyone have any suggestions? I can imagine this is a common issue...

Simon.
 

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Discussion Starter #3
Hi, I have bled the fluid on both sides and it come out quickly and without bubbles. The pistons do move freely and the handbrake seems to work on both sides evenly.
I also checked the caliper slided were free moving.. So I am a bit of a loss...
 
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By "handbrake" do you mean the caliper or cable?

Could be the cable is rusty.

wrinx
 

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Discussion Starter #5
The handbrake works fine, the cable is ok, it's just the hydraulic part of the rear brake that is giving poor effort.
After heavy braking the disc on one side is very hot as you would expect, but the other side is not very hot. :confused:
 
W

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Sounds like one piston is not working properly...although you say they're moving freely?

Did you set the piston so the pads are near the wheels before putting it back together?

wrinx
 

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Discussion Starter #7
I did set the pistons correctly by pumping the brake until both pads were close to the disc, before setting the handbrake. This method was recommanded on the Fiat coupe forum..
 
W

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Yeah, that's one way, the other is to just turn the caliper out prior to fitting.

Dunno about this now...anyone else???

wrinx
 

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hi,you have to make sure that the piston is tight on the pads.because it is a.b.s when the system starts up the piston move's back very slightly.you should use a tool to push the piston back,as you push it back it also turns.the hand break lever on the back of the caliper should be free,test this by taking the cable off the caliper then opperating it by hand.as you opperate it you should see the piston come out,if it does its ok.when you put it together again,make sure the cable is slackened right off.on the pad it will have a locating piece,like a piece of rounded metal,turn the piston until one of the slots on the piston meet up with it.adjust the cable and that should be that.oh make sure all seals are ok,ie dust seals
 

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Not sure I'm on the right road here, but reckon you guys are. Correct me if I am way off beam, but do the rear calipers have a self adjusting mechanism, which is coarse worm threaded? Tool always required to wind back fully, prior to auto adjustment becoming effective? As always, not really sure, just hazarding a probably wrong guess!
 

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"the hand break lever on the back of the caliper should be free,test this by taking the cable off the caliper then opperating it by hand.as you opperate it you should see the piston come out,if it does its ok."

Yes, if the handbrake is not relaxed, i.e. if it's been adjusted so that the operating lever is not back against its stop I think the self-adjusting action can be defeated. Very often people imagine they can 'adjust' the handbrake using the threaded ends of the cables and muck up the system. This adjustment is there to accomodate differences in cable length NOT to accomodate wear and it definitely doesn't help at the MOT!
Otherwise, as above, hoses rubber swells up over time, but because the hoses have fabric stiffening thier walls, this swelling leads to the fluid passage being closed up. The first sign of this is likely to be brakes binding on though. It takes a good many years.
 

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Hi wrenched is right in what he is saying.all mechanism's have to work and be free,by hand is the best way to find out.replace the springs if need be,because they pull the hand brake lever on the caliper back,thats why it is crucial that you adjust the piston as close to the pads to start of with.once you have done this adjust the cable.
 

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H'mn, Absorbing theme this one, if the calipers are of the Internal Butt thread self adjusting type, I know they are a seriously difficult type to overhaul, if piston sticking/seal probs are evident. Easier to fit a replacement caliper. Perhaps they are not the type I have in mind, so my opinions are null and void. Apologies if this is the case! P.S. Have in the past, found it is the adjustment that is often , but not always,problem.
 

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Discussion Starter #14
I just want to add to this thread now that it seems to have sorted itself out. Although the handbrake is still nothing special. I did manage a handbrake turn in a field the other day though. :D

I think I will replace the cable when the weather gets a bit warmer/less wet.
 

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"Internal Butt thread "

You Butt!

No ButtyesButtnoButt....

Can't remember when I last had one of these to pieces. It's not funny this memory thing. I do remember the cylinders on the early Dunlop system (Jags & Jensens, 1950s).
Oh Doctor.....
 

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PS they had a sort of non-return spring in them to stop the pads moving back... see there was a connection
 

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Yea Right on Wrenched, memory degredation, just as well I'm not let loose on the real thing anymore. Vague re-collections of Dunlop brakes, pretty Naff compared to modern systems. Inboard on 'E's and 'S' types, or have I got this one wrong? Thanks for putting me in my place, well deserved!!!
 

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zulu ferret said:
if the calipers are of the Internal Butt thread self adjusting type, I know they are a seriously difficult type to overhaul,
Yes, they are a variant of the Lucas-Girling 'Colette' caliper. Not too bad an overhaul job if you've got the appropriate special tools, apparently......

The handbrake mechanisms on my Peugeot 405 had a tendency to seize. I managed to dismantle the calipers, with a lot of difficulty, improvisation & cussing, & sort the problem, but I had to re-use the existing seals as repair kits just weren't available. There's always a lot of satisfaction in jobs like that where you've beaten the system & done something they didn't want you to do!
 

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Ahh La Belle Colette... Le cafe, le Gauloises,... le grand lt....

I had a Matra (STOP laughing) well 3 actually in the end, although one lived in the loft. That was where I first came across these pesky handbrakes.
Still, going back to the Jags, not a patch on the handbrake system on the Girling for Total Naffness. Fit new pads... drive to MOT station (careful-not tooo far)....drive back form test....handbrake completely ineffective!
 
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