HELP! BRAKES! ARRRRRGHHH! - Larger Servo/MC Upgrade

[Risocco]

Right-ho, the car went for its MOT and failed on the brakes, basically feels like they need bleeding again, no feel in the pedal and loads of travel, mechanics attempted this but they are only getting air from two of the valves in the master cylinder, no fluid.

The car has the 9 inch Servo and 22mm master cylinder upgrade on it, so what have I done wrong? Can not getting the correct length on the servo arm affect this at all, as the standard servo and larger one are different? Or could it be something else?

Master cylinder is brand new by the way.

Really at the end of my tether with this car at the moment, any help would be grand.

[Tim_R]

When you fitted the servo, did you use the original scirocco clevis pin and shorten the rod threaded rod on the servo by about 10mm? That's what I had to do with mine.

Are you getting air out the front or rear outlets on the M/C and are you using all 4, one for each wheel?

[Risocco]

Hi mate, yeah did all the above, would like to think I got the distances correct. There is no fluid coming to the fronts I believe.

I did reuse the original valves tho, wondering if that's the issue? It is a 4 output MC too.

[ChrisPears]

Are the valves you re-used the proportioning valves? They should be on the back lines to vary the pressure going to the back brakes to avoid lock ups.

Have you tried pressure bleeding the brakes? Get an Ezi-Bleed on there and it should push the fluid through. You can combine the manual and ezi-bleed method, its the only way I can get my brakes to bleed properly.

[Risocco]

Doh, forgot about this thread.

Yeah, the only way I could start the bleeding process was with an ezi-bleed kit.

Anyway, all sorted now, was a duff Master Cylinder in the end. Ta for the input tho chaps