Excessive brake pedal travel

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Sensible_Steve
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Excessive brake pedal travel

Post by Sensible_Steve »

High all,

Just done a replacement of the front brake discs, new bearings and new pads as the old discs were heavily grooved/pitted/rusty and excessively noisey. The brakes used to operate okay, with no pulling etc. But obviously not as efficient as they could be. 1984 camper - 1.9 petrol water cooled.

Now it is all back together I now have an issue. I have excessive travel of the brake pedal on first application. If I re-apply the brake just once, immediately, normal service is resumed, for a while. A couple of minutes later I am back to square one with excessive brake travel - although the brakes do bite on initially application, it is towards the bottom of the brake pedal travel.

Although the old pads had loads of meat on them, I did have to push the caliper pistons back into the calipers a little bit to aid fitting of the new pads. I also did not break into the hydraulics, when doing this work.

Does this mean I have an issue with a brake master cyclinder - internal piston seals? Wiki seams to hint at this. Or will could this problem be fixed by bleeding the brakes through with new fluid. We did notice that the fluid had taken on some colour, indicating that it is due for a change.

Comments appreciated.

billy739
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Re: Excessive brake pedal travel

Post by billy739 »

try bleeding the brakes. but be carefull you dont snap any bleed nipples

good excuse to do the 2 yearly brake fluid change !

may also be worth putting your location in your profile as if your in gloucester i could pop over and take a look if you still have problems

Sensible_Steve
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Re: Excessive brake pedal travel

Post by Sensible_Steve »

I will get some brake fluid today and try a bleed through tonight if the rain stays off.

I am close by in the 'much maligned' Swindon Town.

I jumped in the cab this morning and press the brake pedal and it was rock solid, after being left all night. However I had not started the engine. Which was odd.

Cheers

Steve H

billy739
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Re: Excessive brake pedal travel

Post by billy739 »

obviously there is a certain amount of bedding in needed with new pads but should not be as much as you have!

no harsh braking for a couple of hundred miles is always advisable - if possible

California Dreamin
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Re: Excessive brake pedal travel

Post by California Dreamin »

Definately bleed at ALL FOUR corners starting with the furthest away from the master cylinder first. Do not allow the fluid to drop too low and draw in air at any point otherwise you will be back to square one.

Solid brake pedal on the first application (no engine) hmmm, the brake servo should really be able to hold some vacuum overnight, perhaps two pumps before going solid. There is an outside chance that the one way valve in the vacuum pipe may be faulty.

Whilst you're bleeding the rear brakes you might as well manually adjust the shoes up to give you the best possible pedal action.

Martin
1989 California 2.1MV

stecats
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Re: Excessive brake pedal travel

Post by stecats »

I have a similar problem. Brake pedal travelling on first push about half way down then fine on second push. Did you get this sorted out? There is also a hissing sound which seems to be coming from the servo each time i press the brakes. also when I pull the handbrake the foot brake pedal moves slightly. Also I'm not sure if it is connected but this started to happen straight after a big cloud of white smoke came out of the exhaust on the motorway then shortly afterwards had a rear tyre blowout. any answers

billy739
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Re: Excessive brake pedal travel

Post by billy739 »

loose whell bearing?

small noise from servo can be normal.

try running engine , put foot on brake not hard but so you get max travel , keep foot still and switch off engine.

does your foot get pushed up within a minute (could be a few seconds) if yes then the servo system has an air leak.

movement withthe h/brake being applied is normal - your taking the slack on the rear brakes.
the rears are auto adjust , but they can seize and you can adjust them before the auto adjusters kick in!

stecats
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Re: Excessive brake pedal travel

Post by stecats »

will give that a go. Also after a few miles the front offside tyre is making a squealing sound on and off which comes and goes when braking. do you think it could be the bearing and will this explain the brake pedal travel. how easy is it to fix or is it a trip to the garage. Cheers

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kevtherev
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Re: Excessive brake pedal travel

Post by kevtherev »

stecats wrote:will give that a go. Also after a few miles the front offside tyre is making a squealing sound on and off which comes and goes when braking. do you think it could be the bearing and will this explain the brake pedal travel. how easy is it to fix or is it a trip to the garage. Cheers
not a bearing it means you didn't apply copperslip grease the back of the new pads.

re the travel. @ sensible steve
Is the handbrake adjusted properly?
AGG 2.0L 8V. (Golf GTi MkIII)

stecats
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Re: Excessive brake pedal travel

Post by stecats »

so would this explain the travel in the pedal and how can i sort this out.

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kevtherev
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Re: Excessive brake pedal travel

Post by kevtherev »

No grease wont explain the travel
Grease stops the squeal.
Travel is from air, mastercylinder, poorly adjusted hand brake
all of which are explained fully in your haynes manual
AGG 2.0L 8V. (Golf GTi MkIII)

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