undulattice 0 Posted July 10, 2010 Bled my brakes today using one of these kits, followed the instructions and connected it to my spare at 20psi. Undid the bleed nuts on the back brakes and no fluid came through, had to get someone to press the pedal in order to get any movement. Moved to the front and the old fluid came out as it should with no need to press the pedal - also worked fine on the clutch. Anyone know why it didn't work on the rears? Not enough pressure? Did the job anyway as the brakes feel much better and I suppose it was handy as I didn't have to keep topping up the fluid. Quote Share this post Link to post Share on other sites
Toad 0 Posted July 10, 2010 You need to hold the bias valve open on the rear beam. Admittedly, some fluid should come through, just slowly. Quote Share this post Link to post Share on other sites
undulattice 0 Posted July 10, 2010 You need to hold the bias valve open on the rear beam. Admittedly, some fluid should come through, just slowly. Ah that makes sense. For future reference, would jacking under the rear beam hold the bias valve open? Cheers. Quote Share this post Link to post Share on other sites
Mawrick 0 Posted July 10, 2010 I actually think you have to have the car running (at least the brake system have to be pressureized). I had the exact same trouble with my rare brakes after the rebuild, the system had been sitting without power for months, and when trying to bleed the rare brakes (before the engine re fitted), we where able to draw some fluid thru with a vacuum bleeder thingy - but when trying to bleed em properly with the pedal - not fluid came out. After getting the ignition on it worked just fine.........it seem like it have to pressurise the brake system before you can bleed the rear ones :) Quote Share this post Link to post Share on other sites
RW1 0 Posted July 10, 2010 Bled my brakes today using one of these kits, followed the instructions and connected it to my spare at 20psi. Undid the bleed nuts on the back brakes and no fluid came through, had to get someone to press the pedal in order to get any movement. Moved to the front and the old fluid came out as it should with no need to press the pedal - also worked fine on the clutch. Anyone know why it didn't work on the rears? Not enough pressure? Did the job anyway as the brakes feel much better and I suppose it was handy as I didn't have to keep topping up the fluid. A few things... 1) There is a pressure /compensator restrictor in the rear cicuits which will restrict flow if the Corrado was jacked up. The compensator is on the passenger side on the axle beam just inside of the tfront of the rear tyre. 2) The compensator is blocked. 3) You may have collapsed internals in the rubber rear brake hoses which will can block the flow. If the Corrado wasn't jacked up at the rear, I'd look at 3) first as below. Usually for 3), using brake pedal pressure causes flow but as soon as pedal pressure is released, flow stops. The only way to check is remove the brake hose and look through it. The usual culprit is the one behind the rear brake disc on the axle. The other is the body to axle beam. If the one behind rear disc is OK, then look at this next. You may have had hot rear discs in the recent past which will be characterised by the disc areas looking cleaner and free from oily type deposits. This because the fluid gets through to apply pressure to the brake pads but subsequently cannot back flow to relieve the brake pad pressure. . Quote Share this post Link to post Share on other sites
dukest 0 Posted July 10, 2010 bled my rears using eezibleed 2 weeks ago after letting them drip fluid (ie. lose pressure) with the calipers off for at least 4 hours beforehand - no issues at all. dont know if that is much help but perhaps at least points to something else causing problems with your system (compensator as mentioned etc.) Quote Share this post Link to post Share on other sites
steveo29 0 Posted July 12, 2010 its the compensator valve ..needs forcing open with a cable or string etc fronts always bleed faster than the rears in my experiance Quote Share this post Link to post Share on other sites
dukest 0 Posted July 12, 2010 its the compensator valve ..needs forcing open with a cable or string etc fronts always bleed faster than the rears in my experiance thinking about it mine was on axle stands holding the beam up so i guess that's why mine was ok.. Quote Share this post Link to post Share on other sites
undulattice 0 Posted July 12, 2010 Cheers for the responses, will know for next time. Quote Share this post Link to post Share on other sites
Supercharged 2 Posted July 12, 2010 I actually think you have to have the car running (at least the brake system have to be pressureized). I had the exact same trouble with my rare brakes after the rebuild, the system had been sitting without power for months, and when trying to bleed the rare brakes (before the engine re fitted), we where able to draw some fluid thru with a vacuum bleeder thingy - but when trying to bleed em properly with the pedal - not fluid came out. After getting the ignition on it worked just fine.........it seem like it have to pressurise the brake system before you can bleed the rear ones :) You may have to on yours Mawrick but not on the Teves MKIV system we got in the UK... VAG say bleed with the weight of the car on the ground (ramp) but as above you can get round this by opening the comp valve. As RW1 says though - if no flow or flow stops then very likely to be a collapsed flexi pipe or faulty valve unit. Quote Share this post Link to post Share on other sites
