Need some direction on Brakes not working properly before I turn over to professional. 2004 disco 2 SE7 Trail Edition.

Vehicle has stainless steel brake lines (4 wheels) and 2 new non stainless (short connecting hoses) installed about
8 months ago. Also installed new rotors and pads at the same time. Flushed fluid, etc. All working well but I knew the master cylinder would be next to rebuild or replace (soft pedal, etc).

About a month ago brakes would go to floor when braking.. Vehicle would still stop but barely (not safe to drive)

At that point I bought a mc re-build kit, installed, bled mc then bled at all 4 wheels several times. Brakes were better but the vehicle wouldn't stop quickly (compared to my 01 disco and other vehicles). I couldn't get the brakes to lock the wheels and engage the abs (except on gravel). You could tell they weren't 100%'

So.. figured if I replaced everything it would have to solve the problem Replaced brake booster (reman. I know the warnings about those) and master cylinder with a new one (Dorman brand). Re-bled mc and at wheels ,etc.

At this point all is new but same outcome. Vehicle is driveable but it doesn't stop quick enough (no matter how hard I slame on brakes). Hard to explain but it just rolls to a slow stop instead of stopping immediately like it should.
Almost feels like a brake booster issue.

I've bled the darn thing countless times by the rave manual as well as engage abs on gravel, then re-bleed.

Also have checked brake booster hose that feeds into the plenum. If I unplug it the vehicle sputters and dies. Assuming that is working fine.

I dunno.. Any ideas of something I haven't checked or missed ?

thanks in advance !!

Scott

 

You have to engage the ABS and then bleed more. There are several scan tool devices that will do this or a few hacks that can engage the ABS system, or you can put it in low range and activate the HDC while driving slowly. Then bleed more.

 

thanks Dave. I'll try that next.

 

X1 .............. problem is the ABS module needs activating and bleeding properly, A + B circuits, the easiest way is to hire, beg, borrow or steal a suitable diag tool like Britpart Lynx, Nanocom, Hawkeye or similar (to buy outright they'll set you back around $450) and follow the online instructions on them. Once done then bleed the whole system conventionally but ensure you keep the brake reservoir topped up well above minimum or you'll need to start over again.

 

Why do they not recommend bench bleeding the master cylinder prior to install ? I was thinking that should have been done first and maybe that was my issue.. that I still had air bubbles trapped in the MC. although I've bled the system countless times it seems like. Went out yesterday and activated the abs on gravel several times and re-bled 2x but still "soft". I may try to track down diag tool like you suggested.

 

Alright.. Ordered Foxwell NT-510 that will do abs activated bleeding as well.. $150. Just need to know if I need to take MC out and bench bleed it first. thanks!

 

Get a push-button starter switch or any push-button. Attach two wires long enough to go from the fuse box under the hood to the furthest wheel. Crimp two male spade connectors to each wire. Find and pull ABS relay in fuse box. Look at schematic on relay, find contact closure points and where they plug into in the fuse box. Trim spades if you have to, to fit into those spots in the fuse box. Push button, you'll here the ABS pump engage (Key-on). Bleed brakes again using pump to do your work for you. (Keep reservoir full; DOT4) Job done. Easiest. brake-bleed. ever.

 

Bleed the master cylinder manually while it’s installeed. While assistant pushes on pedal, bleed at the 2 lines going into the abs modulator.

Then use whatever method to bleed the actual modulator and lines post modulator.

 

got it.. I did bleed it manually while installed but probably not good enough. wjsj69, I've read about that but hesitated trying it. will probably wait for my Foxwell to come in and bleed abs with that.

 

Using the Foxwell makes it so much easier to power bleed the abs module. It shows you how to do it step by step.