Long Brake Pedal

I've replaced the brake pads but I still have a long brake pedal? Fluid seems ok but have just brought some more & will top-up shortly.

Do I need to look at the calipers?

Reply to
gospvg
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replacing pads should not make any difference to pedal travel. If the pedal is spongy when pressed there may be air in the system. If the pedal just go goes a long way then operates normally then it would either indicate very maladjusted drm brakes or a failed master cylinder.

To establish where the (long pedal, not spongy) fault is: get 4 sets of brake pipe clamps (or carefully use mole grips) put one on the flexible brake hose to each wheel, try the pedal, it should scarcely move at all, remove one set at a time and recheck the pedal, movement should increase by a little with each brake that is allowed to operate, hopefully you will be able to tell which one induces the most movement and can narrow down the fault.

Reply to
Mrcheerful

"Mrcheerful" gurgled happily, sounding much like they were saying:

It will at first, as the pads get pushed back towards the disk - especially if the disks are a bit thin.

It may also be that the caliper bores are a bit dodgy, and retracting the pistons has caused the seals not to.

You could, of course, just use one set - move it around each corner, seeing which corner takes most travel out of the pedal. It also gives a good chance to have a look at the flexis to see if one's looking knackered enough to balloon under pressure.

Reply to
Adrian

Once the pads are pushed out (one or two presses) the pedal travel should be stable and exactly as before changing pads (op said that he STILL has a long pedal travel, so there was a fault before the pad change, so piston/seal fault if any must be pre-existing). Using four clamps is better since it shows that the master cylinder can work properly.

Mrcheerful

Reply to
Mrcheerful

Thanks for the advice - a nice little job for the weekend then :)

Reply to
gospvg

gospvg explained on 04/12/2008 :

If you have replaced the pads because of the long travel, then that was the wrong thing to do. New pads, especially on old disks, can cause some some sponginess until they bed in, but there should be no excess travel until they start to bite.

To check travel, the best way is to press the pedal down without the engine and servo running - you may need to pump it several times to discharge the vacuum completely. Travel then should be about half an inch or so.

Reply to
Harry Bloomfield

Hey nice tip from MrCheerful there. I'm only an occasional car-fixer :-) but have been so for a few decades. Never heard that one before. I wonder would those plastic capped clamps (used for woodworking) would do? Perhaps they aren't enough pressure to close the hose down. Should be straighforward to make some from round metal bar and a few bolts.

Reply to
dave

You can, but they are only £3 each.

Reply to
Duncan Wood

Might need bleeding. Might be excessive side play in the wheel bearings or run out on the discs - if you pump the brakes with the car stationary but engine running - then don't touch them for a couple of minutes is the excessive travel still there? Was the car ever ok in this respect? Could be the self adjusters on the rear brakes - if it has them.

Reply to
Dave Plowman (News)

Have you done many miles since fitting the pads. It makes a big difference when they get bedded in.

Reply to
John

If you have drums at the rear; check the handbrake cable and also adjust the brake shoes to remove the free travel that develops as they wear (only if the adjustment is manual or the auto adjuster has seized).

Reply to
Chris Dugan

Yes I have tried this when the car is turned off I pump the brake pedal and after about 2 or 3 presses it becomes very hard. But when I start the car the pedal goes very long again :(

Reply to
gospvg

Nope just the usual 10 mile round trip to work every day & local driving.

Reply to
gospvg

You have a non-problem. It will be fine in couple of weeks. This often happens.

Steve

Reply to
shazzbat

Due to their construction, knackered hoses don't balloon under pressure. If they did they would burst.

Steve

Reply to
shazzbat

"shazzbat" gurgled happily, sounding much like they were saying:

I must have imagined them, then.

Reply to
Adrian

Really?

Reply to
gospvg

they can do, I have seen them very occasionally, the hoses are double walled, the failure mode is that the inner liner fails allowing fluid into the space between the inner and outer, the outer then swells when the pedal is pressed and can burst. This is why one of the MoT tasks is to stand on the pedal while the hoses are inspected..

Mrcheerful

Reply to
Mrcheerful

he means that it can happen AFTER fitting new pads against worn discs, at first the new flat pads only touch at the edges, after a week or two they touch all over and pedal travel reduces. You had a fault before fitting new pads and it has not changed AIUI

Reply to
Mrcheerful

Yes I thought that new pads will fix the problem but nope. I may just give it another week to make sure

Reply to
gospvg

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