Spongy Brakes - help pls

Need technical Q/A then you're in the right place

Moderator: martauto

Post Reply
capri_rob
Married to the E30 Zone
Married to the E30 Zone
Posts: 9681
Joined: Tue Feb 19, 2008 11:00 pm
Location: South Staffordshire

Sun Mar 07, 2010 7:56 am

OK after replacing front and rear disks, pads and rear brake pipes and after thoroughly bleeding the brakes through, there is still loads of pedal travel and the brakes are still pretty spongy.

Is this likely to be a knackered master cylinder or ABS pump or both ? which should I be replacing first ?

Its definately not air in the system as we spent a lot of time making sure that the system is fully bled through with new fluid.

The pedal goes about halfway down before any braking effect takes place - I know that the new disks and pads will take a while to bed in but they really should start to bite nearer the top of the pedal travel than they do.

What I don't want to do is spend money replacing the wrong bits so any help as to the most likely cause would be appreciated :D
Image

e30topless said : Proper BMW's have 4 headlights, last of the run was the E30 and E34/E32 anything after that is just complete shite
BillyW
E30 Zone Newbie
E30 Zone Newbie
Posts: 118
Joined: Tue Sep 01, 2009 11:00 pm
Location: Bournemouth

Sun Mar 07, 2010 8:09 am

im sure you can actually adjust brake pedal hight on these, i may be talking rubbish though! :mad:
daimlerman
**BANNED**
Posts: 15968
Joined: Mon Feb 27, 2006 11:00 pm
Location: Grumpy Old Man

Sun Mar 07, 2010 10:35 am

I had problems like this,as well.
My issue was little/no brakes at the rear,similar to bumhole's problems of a week or two back.
I established that fluid was reaching the ABS pump,was passing through the ABS pump and was suspecting the restrictor valve mounted on the l/h inner wing just below the brake master.
I was unable to prove that this was receiving fluid/passing fluid without destroying the pipework/valve,but found just in time that my problem centred around the output pipe from the ABS,and tightening this fitting properly :o: solved my problem.
Youth is wasted on the young.
Cook318IS
E30 Zone Addict
E30 Zone Addict
Posts: 4587
Joined: Fri Jun 08, 2007 11:00 pm
Location: Torquay
Contact:

Sun Mar 07, 2010 10:38 am

your brake hoses aren't perishing are they?
Image
capri_rob
Married to the E30 Zone
Married to the E30 Zone
Posts: 9681
Joined: Tue Feb 19, 2008 11:00 pm
Location: South Staffordshire

Sun Mar 07, 2010 11:14 am

Flexi hoses are all in reasonably good condition - I've had the car just over 2 Years and not had to replace them and they have passed an MOT just over a month ago without any advisory.

Brian I will check the fittings to the ABS pump and report back :)
Image

e30topless said : Proper BMW's have 4 headlights, last of the run was the E30 and E34/E32 anything after that is just complete shite
Post Reply