GolfGTIforum.co.uk
Model specific boards => Golf mk2 => Topic started by: Horney on 31 October 2006, 18:08
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Hi Guys,
Replaced the caliper on the side that the handbrake failed on with a recon one (couldn't afford a pair of MKIII ones). I've blead it and blead all the others several time and still the peddle goes to the floor.
Also the handbrake still doesn't work on that side. The cable pulls up fine and the mechanism goes all the way round to the stop and yet still the wheel turns freely with the handbrake on, what's going on?
Please help I have till friday morning to sort it before the MOT retest.
Cheers folks,
Nick
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Oh yeah pads and discs have loads of meat on em so that's not the problem.
Nick
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What did you use to bleed the system? Did you bleed the system with the brake bias valve on the rear axle fully open?
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The what? TBH I didn't read the haynes manual for brake bleeding. I just went ahead and did it. I was getting plenty of fluid through without bubbles.
To bleed the brakes I used an Eezibleed style pipe to stop it sucking back any air.
Nick
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You still not fixed it! :grin:
On the rear beam theres a rear brake bias valve, you need to clamp it open before you bleed the brakes. If you imagine how the beam would move when it is pushed upwards by weight in the rear, thats how the valve needs to be clamped open. Oh and I have some bad news, if the pedal has gone to the floor chances are the master cylinder is now buggered!
Also some calipers have the bleed screw at the bottom, if this is the case on yours take it off and flip it upside down :)
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Humm ok given me some things to think about.
How does the bias valve effect bleeding? I get plenty of fluid through so I can't see how that effects things?
I can understand the problem of the nipple, didn't think of that. Are you saying to remove the caliper, bleed it off the car up side down and then refit?
The peddle does go to the floor but if you pump it it does harden up so I'm prety sure it's just air trapped somewhere and not the master.
Nick
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Until you get the system bled propperly the handbrake wont work as the adjuster will not adjust.
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If the bias isn't fully open it can trap air in it, and you wont get a good strong flow of fluid thru to the rear brakes.
Yeah just unbolt the caliper and hang it upside down to bleed, then refit.
Problem is, if the pedal goes to the floor you normally end up tearing the seals inside unless its very new. After this the cylinder is never the same again :(
This doesn't explain the problem with the rear caliper though, that is most probably air in the system :)
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Oh arse biscuits. I can't afford to replace the master I'll just have to keep my fingers crossed it's ok.
Nick
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Oh and hanging the caliper upside down while bleeding wont work if your bleeding the old fashioned pumping the pedal way as the piston will just pop out. But it will be fine to do this if using a pressure bleed kit.
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what about if you clamp the cylinder in with a G clamp or something?
TBH, buy an Eezi Bleed, best £10 or so you'll spend. Makes brake bleeding an effortless 1 man job :)
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Buy an eezibleed kit? Meh I have my own home made one that works a treat.
I'll give it another bash tonight. I have pipe clamps that I used when I removed the caliper so really should only have lost about 1" of fluid in the flexi and need to flush the air out of the caliper I replaced.
Nick
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does it work off pressure from a spare tire, or do you have to pump the pedal. If you have to pump the pedal, buy an eezi bleed ;)
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Buy an eezibleed kit? Meh I have my own home made one that works a treat.
Eeerrrrmmmmm, Obviously it doesent!
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Eeerrrrmmmmm, how would you know that?
Its not as if an eezi bleed is a complex thing to build up in your shed...
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No it's not pressure fed its a peddle pumper design. It does work a treat I've been using it to bleed brakes on cars for 3 years. This is the first time I have had a problem and the first time I have done rear brake calipers on a MKII Golf. It maybe that this method is not good enough for this model of car.
My neighbour has a pressur ebleeder so I guess I may have to borrow that and give it a go, but that'll be at the weekend so looks like I'll have to cancel my retest and pay full wack for another MOT which will have to wait till next month now as I've run out of money anyway.
Nick
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I have pipe clamps that I used when I removed the caliper so really should only have lost about 1" of fluid in the flexi and need to flush the air out of the caliper I replaced.
Nick
:shocked: Don't clamp flexi pipes, it ain't a washing machine, they're designed not to flex across the diameter, you'll weaken them severely if you do.... :rolleyes:
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Er yeah if you use some sort of bodge clamp. This is a proper brake flexi pipe clamp designed to do the job.
Nick
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:cool: Well, you learn something every day, I never knew such a thing existed..... :smiley:
I just bend mine double and flexi-tie them................not! :grin:
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I just bend mine double and flexi-tie them................not! :grin:
:shocked:
:grin:
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yeah pedal pumping on a MK2 isn't a good plan as it can bugger the master cylinder if you press the pedal too far unfortunatly :cry:
Give it a go with the bias valve clamped open with the pressure bleeder, and flip the caliper upside down if need be. I think this is only an issue when fitting some types of MK3 caliper on a MK2 or something, I'm not sure tbh. Just something I've read that some calipers have the bleed nipple at the bottom :)
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surely it shouldent make any difference where the nipple is as the pressure will push the fluid out anyway.
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Its not the fluid pressure thats the problem, its the air trapped at the top of the caliper thats the issue if the bleed nipple is at the bottom of the caliper :)
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Try jacking up the rear and supporting on axle stands, do this as high as you can get them.
Pump the pedal until you get resistance, but do not press the pedal right to the floor.
Leave the car overnight, any air will settle in the back brakes.
In the morning bleed the brakes using a proper pressure bleed kit with a pressure feed off the spare tyre.
If you are still having problems then try swapping the bleed nipple from the old caliper onto the new one, i have had problems with poorly tappered bleed nipples in the past.
As for clamping brake hoses, of course you can, hasn't anyone read a workshop manual :rolleyes:
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Just to add.
The way this problem would be looked at in a garage would be they would clamp the hose going into each corner, if any cause the pedal to go tight, then your problem is isolated.