Urgent help needed. Serious Brake issue

stec66

Guest
Hi guys.

Im in desperate need of help.

A bit of background info. Im a fully 'trained' motor mechanic and MOT Tester (6 years) and my mums Boyfriend owns a 54 plate Leon FR TDI.
Yesterday I carried out a brake fluid change - Bad idea.
I carried it out the way i would carry any other fluid change out. Furthest calliper first and working my way towards the master Cylinder. Didnt let the reseviour get low on fluid. Everything seemed fine (checked on the roller also) and he left.
As he drove home it appeard that ALL the brakes where starting to bind. By the time he got home the brakes where smoking.

As I work 25 miles away we arrannged for him to take it to another garage closer to home which is owned by the same company. (this isnt a garage job , just helping me out)

They have tried going through the Dry bleed sequence on the Bosch machine but its makng no difference.

The brake pedal is now very hard and all the brakes are binding fairly heavily. The car is dangerous to drive.

Has anybody ever come accross this before? Iits driving me mad (and the other mechanics too) and certainly my mums boyfriend although he is being very nice about it :(

Im terrified that its the ABS unit, but am hoping its the Master cylinder. Thing is its now stuck at the garage and was wondering is it worth asking them to Fit a master Cylinder before taking it to the dreaded main Dealer? Want to try make a decision by moring when we go down.

Any advise it mega appreciated as this is stressing me out.

Thank you
 

sonnex22

Active Member
Jul 26, 2010
77
1
did you run the ABS pump while bleeding the brakes? i think you need to but am sure i will get corrected.
 

stec66

Guest
NO i didnt. carried out fluid changes on Golfs before this way no problem. Only thought the pump had to be on if the fluid had been drained. (to release any air). I may be wrong though.........
 

hyphon12

Daft Member
Jun 7, 2011
1,106
5
Scottish Borders
What m0rk said, how did you bleed it? If you've vacuum bled it then that could be why, I've heard other people with similar problems after using a vac bleed system. I've always used a 2bar Pressurised system on all cars I work on and never have such a bother.
 

stec66

Guest
Sorry. Pumping of pedals About 10 pumps on each. No signs of air in the fluid, and plenty coming out of the bleed nipples.

Im aware the seals could have been rolled pumping pedals. its never happened to me before though :( .. always a first time though. IF this is the problem then we will just replace the Clyinder
 

stec66

Guest
ok. Ill give it a go in the morning before we commit to a repair. how would this casue the brakes to bind. Anyone know the science behind it.

Does this sound like a cylinder rather than ABS pump problem? No warning lamp illuminated
 

stec66

Guest
The lads have already done it with the Bosch machine. no change......
 

stec66

Guest
The pedal is just hard from the very top and moves very little. The brakes work....probelm is they slightly work all the time.
 

hyphon12

Daft Member
Jun 7, 2011
1,106
5
Scottish Borders
Well if the master cylinder rod is adjustable then that sounds a possible fault to me.

I know the passats have an adjustment on the rod at the pedal so wouldn't surprise me if the golf/leon is similar. Maybe you've done nothing wrong, maybe previous mechanics have and "bodged" a slack pedal by adjusting the rod?

If you want I'll have a look round my car and see if there is such a thing?
 
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stec66

Guest
Ill check it tomorrow. so much for my day off lol.

Bit stange how it was fine before the fluid change...... baffled
 

Donny9835

Active Member
Nov 8, 2011
34
1
Wiltshire
Got the same problem on a Landrover Defender at work, ended up changing all the pads, callipers, master cylinder, servo assy, vacuum pump and associated pipes, system bleeds fine but still have the hard pedal as if here is no servo assist. Only thing i can think of is that the spilt braking system has gone tits up and wont let the pistons return or fluid to flow back to the reservoir.
 

rallynut

Active Member
Dec 25, 2008
280
0
what about that vacum pipe that leads to the brake servo it sometimes splits that would cause a super hard pedal not sure if this would cause the brakes to bind mind?
 
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