Bleeding brakes

Hi Everyone,

I have changed the brake pipes and flexis for both front brakes. Got them all changed no leaks or anything and had to change both bleeding nipples. Bled the brakes up but don't seem to have a good pedal and have really poor performance from the brakes. The reservoir was empty, would there be air in the whole system from disconnecting at the ABS Block?

Appreciate any help.

Thanks

When I replaced the ABS modulator/pump on mine - my reservoir never emptied, so you possibly have more air in your system than I did in mine.

I did a complete bleed of all 4 corners, I even had to remove the pipes to the ABS unit and inject fluid to get it pumping correctly (mines the Wabco system).

Even after that first bleed the brakes were not good, so I did another 4 corner bleed and and after that they were good.

I bled a LOT of fluid through the system. I wanted to make sure I'd got all the air out.

I used 1 of those 1 person bleed kits, plastic tubing and bottle that fits over the bleed nipple, and it was easy-as.

Kinger032007 said:

Hi Everyone,

I have changed the brake pipes and flexis for both front brakes. Got them all changed no leaks or anything and had to change both bleeding nipples. Bled the brakes up but don't seem to have a good pedal and have really poor performance from the brakes. The reservoir was empty, would there be air in the whole system from disconnecting at the ABS Block?

Appreciate any help.

Thanks

Click to expand...

If the reservoir was allowed to empty, then air will have got into the ABS modulator. The only sure way to get all the air out is to pressure bleed the system, going around the vehicle multiple times.
When working on ABS systems, it's pretty essential to keep the reservoir full of fluid, or air will get in.

Hi,

Thanks for the response.

I have changed the rear cylinders, drums and shoes and tried bleeding the system with an EZ bleed. I managed to get air through but it didn't seem to come out with any real power which makes me think they aren't fully bled as there is still no real braking power. I looked under the bonnet and there was a pipe vacuum pipe which had popped off, would this stop the brakes from bleeding well?

Also from changing drums and shoes the handbrake is non existent, I've pumped the pedal as I have read on here but nothing changed!

Any help would be appreciated.

Thanks

Having separated the ABS modulator from part of the system there will still be air in the ABS block I guess. When I rebuilt the rear of my TD4 I replaced both the rear brake lines in their entirety. I tried to inject fluid into the modulator block but with little success. I bled the system fully two to three times to no real effect so decided to use a diagnostic computer I had. That bled the brakes perfectly. The system requires the front left, front right, rear left rear right brakes to be bled.. in that order! Before that a conventional brake bleed is required to get the brakes in the ‘ball park’. The brakes on my TD4 are spot on but only because I had the diagnostic tool which guided me through the prodecdure at every stage.. if you can get a ‘pedal’ then you may need to take it to a specialist with the right tool to finish the job. I bought my Toughbook online for £150 which came with Delphi diagnostics and it paid for itself on the first use of it.. I also have downloaded VAGCOM onto the hard drive so my VW stuff is covered too..

Handbrake, I've always done it by adjusting so it binds on the drum then back off adjuster slightly. Handbrake passes mot and holds car OK. Not pumping the brake as I found it made no difference.
Air can be trapped in abs module which would need diagnostic tool to make it run, I use delphi clone from ebay with wow software on laptop.

J_D said:

Handbrake, I've always done it by adjusting so it binds on the drum then back off adjuster slightly. Handbrake passes mot and holds car OK. Not pumping the brake as I found it made no difference.
Air can be trapped in abs module which would need diagnostic tool to make it run, I use delphi clone from ebay with wow software on laptop.

Click to expand...

Yes handbrake adjusted as you say.. old school the ‘book’ method has never worked for me.. only locks the brakes even with brand new adjusters..

Thanks for the responses! Does anyone know where I can get a version of Delphi diagnostic?

Thanks

Other diagnostics are available!
Have a look through previous threads for recommendation. Some do specific vehicles and some do many vehicles. You'll need one that is able to operate the abs pump. Pscan gets good reviews on here. Quick eBay check and the launch is just over 100 pounds and is a complete unit.