Master cylinder ordered. Any tips for avoiding getting air in the abs unit whilst fitting it?

No splashing up as such but a flow upwards in the forward chamber is visible.

Back in a minute...

Do i do this test with engine running or can it be done with engine off. She is a noisy beast and i dont want to disturb the neighbors (they put up with a lot and always offer a hand).

Shall do. Am i right in thinking your logic is that a feirce splash from a contracting flexi should produce a visible retun of fluid to the reservoir?

My thoughts also, but having had no bubbles of any significant nature in 3l of brake fluid flushed through since i got the thing a balooning flexi would quite potentially fit the bill.

Many thanks, would your suspected fault be amenable to repair with the rebuild kit or replacement? Cash is tight and i am keen to try and avoid replacing too many expensive components.

Many thanks for your thoughts. If the master cylinder is at fault why does it seem to behave without the servo? Is there a rebuild kit suitable for the abs master cylinder?

Thank you everyone for your continued input. As the book suggests a sequence and i know of no compelling reason to do otherwise i shall be sticking to the disco1 bleed order. I will also have no assistant for my next bleed so will have to resort to the easybleed.

Turns out i didnt have as much dot in the garage as i thought, only 750ml so i took 750 ml through in total. A bit bit off each caliper with the engine running having got under the thing but it will need a more thorough bleed on tuesday as working tomorrow. All the fluid that came out was nice...

Pre bleed servoless test run was very heavy on the brakes but a much more convincing pedal feel. Stopped almost as quickly with a big heave on the pedal as on the stop with the servo working.

Many thanks everyone for some top quality help. The consensus seems to be air in the brake system but master cylinder likely ok, with a potential servo fault if i understand rightly. The rain has died away and i am going out to bleed the thing with the engine idling. i shall then report back.

Many thanks. I used the easybleed at 10psi last time but have access to an assistant today so will go back to the old fashioned approach. I understand there is an option in the electronic voodoo boxes to cycle the abs pump and modulator whilst bleeding but i dont have access to one and cant...

Chaps, i have a P reg disco 1 300tdi with abs that is giving me some bother. With the engine not running the brake pedal is nice and firm, just like the one i had previously without abs. Turn the engine on and the pedal goes soft like there is air in the system, the pedal goes all the way to...

If you pull the vacuum line off the servo whilst the foot is on the brake the pedal lifts up. Some vacuum seems to be maintained after the engine is shut down. I am starting to think the master cylinder is the likely culprit.

Hello chaps, many thanks for so many useful posts over the last few years but now i have got stuck. My P reg disco with the 300tdi and abs has crap brakes. The pedal has a nice firm feel when the engine is off, turn her on and the pedal sinks down to the stop. A nice hissing noise accompanies...