205mattgti 0 Posted October 1, 2006 In the last few days my brakes have suddenly gone crap. i have to pump the peddle once before it stops. i think one of my rear calipers is not working as i did a heat test after a journey and one of the rear calipers was cold. Would a caliper not working do this to the brakes or could it be something else Also could it be an adjustment problem with the rear brakes, if so how do i adjust them. cheer matt Share this post Link to post Share on other sites
inferno 1 Posted October 1, 2006 its all them scoobys and bmw 6 series you keep racing and overtaking insanly when they hit top speed! slow down! Share this post Link to post Share on other sites
jackherer 543 Posted October 1, 2006 if you have to pump the pedal you've either lost fluid through a leak somewhere or the master cylinder is failing. You need to fix it before driving it again IMO. Share this post Link to post Share on other sites
Faz85 0 Posted October 1, 2006 Perhaps the cold caliper has a leak somewhere?? although with that said, a leak would affect the entire braking system. Share this post Link to post Share on other sites
jim21070 2 Posted October 1, 2006 The cold caliper is most likely caused by one of your rear brake load compensators being faulty. The rear brakes account for very little of the overall braking effort so this will not account for the symptoms you describe. There are no adjustments par-se as calipers are by their nature self-adjusting. The rear calipers do however have a special ratchet arrangement on the piston to keep the handbrake in adjustment. When you change rear pads you don't just push the pistons back as you would for the fronts; you have to wind them back by rotating the pistons clockwise. There are special cut-outs to do this. I suggest you bleed the whole brake system and at the same time take the opportunity to change the fluid. If the problems persist, then check all your flexi hoses as these can collapse internally and baloon out under pressure and cause poor braking but if your pedal continues to feel spongy after a good bleed and fluid change and you need to pump to get braking then the Master Cylinder is the most likely culprit as Jackherer says. They're cheap and easy to replace. Wise words from Jackherer. Get it fixed before driving the car again. Don't risk it. Share this post Link to post Share on other sites
TEKNOPUG 3 Posted October 1, 2006 Replace MC, brake lines, compensators, calipers, discs and pads. The brakes will work superbly then. Share this post Link to post Share on other sites
jackherer 543 Posted October 2, 2006 Replace MC, brake lines, compensators, calipers, discs and pads. The brakes will work superbly then. done all that to mine and the bloody servo is failling now so add that to your list Share this post Link to post Share on other sites
Pugnut 9 1 Cars Posted October 2, 2006 Replace MC, brake lines, compensators, calipers, discs and pads. The brakes will work superbly then. done all that to mine and the bloody servo is failling now so add that to your list so keep the original fluid then? Share this post Link to post Share on other sites
jim21070 2 Posted October 2, 2006 so keep the original fluid then? No way!!! That is the first thing to change. Old brake fluid is lethal on at least two levels. Brake fluid is hygroscopic (and not only that, it readily absorbs water from the atmosphere). This causes two major nasties: 1. It lowers the boiling point of the fluid which can cause a vapour-lock under heavy braking as the caliper warms up to beyiond the fluid boiling point and thus causing it to turn to vapour with is compressible. Result, no brakes. 2. The absorbed water causes internal corrosion of all braking components. Result, poor brakes. Share this post Link to post Share on other sites
TEKNOPUG 3 Posted October 2, 2006 pmsl...... totally fished in.... Share this post Link to post Share on other sites
jim21070 2 Posted October 2, 2006 pmsl...... totally fished in.... No, not at all. I knew Pugnut was taking the p*ss but as brakes are so bloody important I felt a serious response was in order just in case anyone was daft enough to do it.. I don't fcuk around where brakes are concerned. Still, it gave you all a good chuckle and if it achieved that on a Monday then good Share this post Link to post Share on other sites
