Ford Focus hatchback, Mk 1 - Brake disc and pad changing

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Sun 12 Aug 2012 21:19
Ford Focus hatchback, Mk 1 - Brake disc and pad changing - argybargy

The Haynes manual for the Focus Mk 1 advises that when changing pads, you should clamp the brake hose and open a bleed nipple when pushing back the caliper piston rather than simply opening up the reservoir cap and letting the pressure go that way. This is apparently because with the latter method, there's a chance that the master cylinder seals would reverse and you would lose braking.

How likely is it that if you don't follow the Haynes advice, the seals would reverse?

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Sun 12 Aug 2012 21:22
Ford Focus hatchback, Mk 1 - Brake disc and pad changing - bathtub tom

Never happened to me (touch wood) in forty years of doing it and I tend to push back the pistons once a year to make sure they're free.

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Sun 12 Aug 2012 21:50
Ford Focus hatchback, Mk 1 - Brake disc and pad changing - gordonbennet

Never happened to me either, but i do push or wind them back if that type very gently, i remove inspect clean and lubricate the brakes every year, so as Tom above i also make sure the pistons are free moving at the same time.

Aside, i slipped a quick fluid renewal in on the old MB faithful a few weeks ago, did it the old up down method with SWMBO doing the pumping, bleeding has sharpened up the brakes noticeably.

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Mon 13 Aug 2012 13:49
Ford Focus hatchback, Mk 1 - Brake disc and pad changing - Robin the Technician

Hi,

I can see their point - because if ythey didn't warn you and it happened - they would be liable. I have changed too many pads in my lifetime and I have never clamped the hose and released the nipple when changing pads. As long as you do it steadliy and methodically I can't see you having a problem.

Hope this helps

Robin the Technician - I fix, therefore i am

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Mon 13 Aug 2012 19:04
Ford Focus hatchback, Mk 1 - Brake disc and pad changing - argybargy

Thanks, all. I don't regularly service my own cars and over the years have probably changed pads and discs only about half a dozen times on different models. On none of those occasions have I "clamped and bled", and it's reassuring to know that Haynes are probably just covering their own backs by issuing that advice.

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Mon 13 Aug 2012 21:48
Ford Focus hatchback, Mk 1 - Brake disc and pad changing - bsm

I've clamped hosees on the two most recent disc/pad changes on a Focus and BMW. The advantage, I've read is that if changing brake fluid at the same time you can expel all old fluid from within the caliper which is the place any water absorbed by the brake fluid is likely to boil under heavy braking, causing a soft pedal.

Mo

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Tue 14 Aug 2012 08:27
Ford Focus hatchback, Mk 1 - Brake disc and pad changing - Collos25
p>How on earth can water enter a fluid that is kept sealed its an old wives tale perpertrated by garages to take some extra money from the gullable customer.

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Tue 14 Aug 2012 09:17
Ford Focus hatchback, Mk 1 - Brake disc and pad changing - madf

Clamp and bleed is the way for ease of operation. Pushing back clipers can be a pia.

"d

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Tue 14 Aug 2012 10:24
Ford Focus hatchback, Mk 1 - Brake disc and pad changing - bathtub tom
p>How on earth can water enter a fluid that is kept sealed its an old wives tale perpertrated by garages to take some extra money from the gullable customer.

I presume you've never seen the breather hole in the top of a fluid reservoir? How else would you prevent a vacuum forming in the reservoir? As the brakes wear, the pistons move out further resulting in a drop in the fluid level.

Try this simple test (jump to 1:40 for the relevant bit): workshop.search-autoparts.com/_Can-You-Believe-Thi...l" target="_blank">workshop.search-autoparts.com/_Can-You-Believe-This/video/486759/31710.html

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Tue 14 Aug 2012 10:42
Ford Focus hatchback, Mk 1 - Brake disc and pad changing - skidpan

Brake fluid attracts moisture (hygroscopic?) and this water reduces the effectiveness of the fluid and reduces the boiling point. Brake fluid should be changed every 2 years because of this.

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