Ideally clamp the brake hose (you can get a proper hose clamp cheap enough). Then break open the nipple before winding piston back. Don't overtighten nipple and put grease around it for next time.
Most premium brand aftermarket pads are fine - delphi, Ferodo, ATE, Textar etc etc.
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Wedging the pedal down has the same effect hydraulically as clamping the hose. I don't like hose clamps as there is always a possibility of damaging the reinforcing cording inside the hose - which cannot be inspected.
In any case, the pedal trick is quicker - secure the pedal and you can do both sides.
659.
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If you are sure the fluid in the system is clean it is best to simply wind the piston back and syphon off the excess from the master cyl if it goes above "max", a syringe is good for this.
If you are concerned about the condition of the fluid to the extent that you are worried about it reaching the ABS pump etc then it is time to change the fluid.
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"it is best to simply wind the piston back and syphon off"
Meant to say this avoids the need for bleeding.
And that i agree with 659 re hose clamps.
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Generally its a bad idea to push fluid back through the system. Some systems are very touchy on this (poss. seal inversion and NRV's in abs hydraulic unit). At GM dealers its almost a sackable offence for a tech to wind back pistons without clamping the hose.
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You can't push any fluid back through the system if the pedal is held depressed to the point at which the recuperation port in the master cylinder is closed off.
659.
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I've fitted EBC Greenstuff pads front and rear to her Golf TDi and the alloys stay much cleaner and clean in a quarter of the time with Wonderwheels than they did with the standard VAG pads.
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My reply is to Cheddars idea of pushing fluid back into master cylinder, which is not a good idea on some systems.
I fully understand that holding piston down will isolate the brake circuit and I guess its an option.
Using a proper brake hose clamp will not damage the hose internally (its standard recomendation in most manufacturer maintenance manuals). If you use something like Mole Grips then you do risk damaging the hose.
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>>At GM dealers its almost a sackable offence for a tech to wind back pistons without clamping the hose.
During my time at a Vauxhall garage, we saw a few occaisons where the seals flipped. Thankfully, it never happened to me. It happened to those who were attempting to maximise their bonus, and I suspect they pushed the pistons back so quickly that they actually managed to produce some pressure in the system. I've never taken any great precautions when pushing pistons back, and, so-far, I haven't had any trouble.
Despite this, I really like the idea of isolating the system suggested by 659 - although I have also never managed to damage a flexi hose by using a clamp with a decent radius. IMO, flexi hoses are more often damaged when people twist them along their length - I've had to stop junior mechanics doing this more than once!
Number_Cruncher
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My opinion of VW pads and thus their OE branded cohorts, is that they deposit corrosive black dots all over the wheels which seem to eat into the paint. Avoid. I replaced the fronts with Mintex which deposits a fine grey dust at about 10th of the rate and can be wiped off with the finger.
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>>My opinion of VW pads and thus their OE branded cohorts, is that they deposit corrosive black dots all over the wheels which seem to eat into the paint.>>
As far as I am aware (I bought my current Bora four years ago when it was three and a half years old), it's still on the original front and rear brake pads. The front wheels get quite a bit of brake dust on the wheel covers but it's very easily cleaned off.
The Bora, again to the best of my knowledge, is still on its original battery and exhaust system....:-)
So buying genuine OEM spare parts from GSF seems, to me at least, to be very sensible.
- - - - - - - - - - - - - - - - - - - - -
What\'s for you won\'t pass you by
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I fitted a set of Halfords own brand pads to the Mondeo just prior to the MOT last year. I'd been too busy to do my pre MOT checks n good time, and left it until the day before. Noticed the front pads were well past their best, and with the test (and work) on Monday, I had to go to Halfords. The Ferodo bits were out of stock, leaving only their own brand parts at something daft like £14.99 for a set of four.
Fitted them initially as a stopgap with a view to changing them for a better known make. Never got around to it, and 10 months and over 20,000 miles later they're only about half worn and the brakes feel fine.
Cheers
DP,
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I stick to genuine spares for everything, It's the only way you can be sure that the parts are dimensionally accurate. This is particularly important with safety-critical parts like brake pads. The material of pattern parts may be OK, but I can't see how the manufacturer could get access to the dimensional tolerances of the OEM parts. Just measuring samples of parts will reveal the dimensions of those particular samples but it won't tell you what the manufacturing tolerances should be.
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L\'escargot.
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With regard to flipped seals, you have to be very heavy handed to do that, surely not a chance with calipers that need winding back, even with conventional calipers gently pushing the piston back cretes such a minimal flow back through the system I cannot see how seals can flip, perhaps clamping the piston back with mole grips etc would be an issue, re Vauxhall my experience with two company Vectra's and three dealers did suggest that some Vaux techs were/are heavy handed.
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But what are genuine spares when it comes to brake pads? I'm not aware of a single car manufacturer that makes brake pads. They buy them in from Ferodo, Delphi, Mintex etc who make them to drawings supplied by the manufacturer.
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I read often, only post occasionally
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Whats more car assemblers don't make brake components or design braking systems either, they just addapt them to the application
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textar, mintex and a few other smaller brands are all made in the same factory at hartlepool, I know as I worked there for a short stint. I dont believe there is an OE part regarding brakes as ford etc dont make their own calipers, hence you always get asked lucas/bendix/ate/girling etc etc.
Personally I buy mintex but I tend to have uprated pads on most my cars. I do bvuy standard for my work horse car and they are usually apex IIRC.
further to 659's method, I think its worth pointing out. remove the old pads before locking down the brake pedal. You will struggle if you dont.
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A couple of weeks ago the MX5 in the family was suffering from brake drag on the front. Both sides would do it but occaisionally only one would play up. New sliders etc did not cure it. We eliminated the servo/master cylinder from the equasion which just left the piston/seal. I dismantled the calipers and found brown stains on the pistons. The fluid in the caliper was clean. I came to the conclusion that it was dust which had collected on the piston when the pads were worn and it had been carried into the bore when the piston had been retracted to fit new pads. A good non-abrasive clean up and re-assembly with new seals seems to have cured the problem.
In future I will be cleaning inside the dust shield thoroughly before retracting any more pistons. I have never had problems with seal reversal but the vehicles I have had probably weren't prone to it.
I would have thought, looking at the relative size of the caliper bore to the bore of the pipework/master cylinder that even a "slow" push back of the caliper piston would give a relatively high fluid velocity back through the system.
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I fitted a set of Halfords own brand pads to the Mondeo just prior to the MOT last year. I'd been too busy to do my pre MOT checks n good time, and left it until the day before. Noticed the front pads were well past their best, and with the test (and work) on Monday, I had to go to Halfords. The Ferodo bits were out of stock, leaving only their own brand parts at something daft like £14.99 for a set of four. Fitted them initially as a stopgap with a view to changing them for a better known make. Never got around to it, and 10 months and over 20,000 miles later they're only about half worn and the brakes feel fine. Cheers DP,
Years ago I fitted a set of Halfords brake pads to the front of a Metro CVT auto, they lasted all of 2 weeks before they where metal to metal again.
Replaced them with Ferodo & 18 months later when I sold the car they where still working & had loads of life left in them, will only ever fit Ferodo pads now.
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