Brake problem

[Cloggy Saint]

I've just replaced my scabby brake servo with a second hand one that I painted. Fitted it, bled the brakes but now when I press the pedal it travels all the way to the floor with no resistance and there's the sound of air escaping in the footwell. Knackered servo or have I done something wrong??

[Cloggy Saint]

bump

[Brianmoooore]

A known genuine E30 servo, or a similar looking one?
Brake servos are designed as 'fail safe' devices, so you shouldn't lose pedal if a servo fails.

[Cloggy Saint]

It's genuine. I do have very slight brakes when the pedal hits the floor.

[Yeti]

pump the brake pedal until its hard when the car is off. once its hard keep your foot pressing on the pedal and start the car the pedal should go down once the engine starts if not the servo is dead or not connected properly or has a leak between the inlet and the pipe.

[Cloggy Saint]

The pedal doesn't go hard, even with the engine off it goes straight to the floor with a rush of air. I've given up on it, I'll paint the original and refit that

[maxfield]

Have you bled the system correctly?

To me I'd say you've still got air in there

[Cloggy Saint]

It was bled properly. I've taken it out now and will refit the original. If the problem persists I'll know it's something else.

[Yeti]

dont bother mate there is air in the system.how did you bleed it? always start with the wheel from the furthest point from the master cylinder then the next closest

[Brianmoooore]

I was making the assumption that the hydraulics weren't touched. If you've had brake lines apart, then it might well be air in the system.

[Cloggy Saint]

I know how to bleed brakes!

[Brianmoooore]

My post further up the page was inspired by what has to be done when fitting an E30 master cylinder to a Clio servo (same make as E30) as part of a M5x engine conversion.
Your problem sounds similar to what you get if no spacer is fitted.
AFAIK, there are no spacers that can be left out if everything is genuine E30 though.

[maxfield]

To add, in the past when bleeding brakes, I've had master cylinder seals roll causing a soft brake pedal.