Disco 1 Disco 1 200tdi | Brakes not 'Biting'

Hi all,

Working on the brakes recently on the disco, not driven for 18 months or so.

Yesterday after bleeding and changing some of the lines went for a careful drive, on pressing the brake pedal this felt hard, but not the usual soft to hard.

The pedal effectively presses the calipers in but the disco takes a while to stop even when pressing down with more force than really required.

Essentially there is no progressive feel to the braking pedal and even on pressing it hard, there is limited feedback.

Thoughts? Air in the system still, although it's been thoroughly bled.

it won't be air causing your lack of "bite" - as air only effects brake pedal travel.
What condition are your discs if they've not been used for so long - inside & external faces? Has 1 or more of the caliper slide pins or pistons siezed?
You need the wheels off & everything checking over for ease of movement.

Take it the servo is working at full whack?

Stanleysteamer said:

Take it the servo is working at full whack?

Click to expand...

First place I would look is the servo as stanleysteamer has said, check you have good vacuum from the vacuum pump and the pipe isn’t leaking, there is a small vacuum pipe that operates the heater recirculating air running from the main vacuum pipe, check it’s in place and not leaking,
If you have changed the pads recently they will take time to bed in so would feel a bit lifeless,

Thanks all - I'll check the servo vacuum first then update this thread.
Haven't changed the pads or discs recently, but thought the build-up for rust etc would run off after some brake tests.

Contaminated pads/discs from the work you've done? As previously said, if it's not been used in 18 months then pistons could be sticking, or caliper rails/sliders

Not contaminated, just been stood for a while - could well be rust on the surface, seized pistons or the servo will check later today thanks!

Hi all,

Thought I would update here - it turned out to be the vacuum pipe that connects into a T-piece which in turn goes into the heating system?

It's slightly concerning as this pipe has split, I cut the end off and reconnected but probably replace this as it's quite a concern that the brakes could lose function so easily.

Is it expected for something so small off a T-piece to stop brake function?

Glad you've found the cause.
No, it's not a surprise that a small pipe can cause a brake problem. Any vacuum leakage reduces the max assistance from the servo.

Cheers Pawl, good to have your feedback.