Passat brakes.

[martin richards]

Iv,e been in the wilderness for a while and lost my way. Have been without and S on my car for nearly a year. After many good years of S2/6 pleasure.
A small question for all. Having troubles with my 98-Passat TDI 110BHP (No laughing).
The front offside disk locked up. No worries i thought and fitted a new caliper. 100 miles later happened again! This time i smealt the rear nearside disc and could smell that too. Ahh i thought, master cylinder. £103 + vat later and all is well. 4k and 5 months down the road and the front offside locked up again. I awaited for it to cool down and drove home.
The ABS is not playing up(i believe). The brake pedal is correctly set!
I know this is not an S2 question, so any suggestions my way will be most appreicated.
Thanks Martin.

[caterpillar]

strange prob...... the load valve i think are gone bad,( in the underside and the rear, of the car) and the brake fluid are only dot 4... not dot 5,1....i use that, i dont save on the brakeunits.

[martin richards]

Thanks for the reply. Just to add further it is a VAG 1.9TDI 4POT.
Have heard about load valves, but was told would not be on a later car. Shall find the haynes book and look through.
Thanks all. Martin

[A1QSHIP]

Brakes Locking Up

With this having occured more than once and with what parts you have already replaced I would say that the rubber hoses at the calipers are suspect. Seen this problem alot on hi-mileage Mercedes Benz cars with infrequent brake fluid changes. As a policy, we do not change the caliper without also changing the hydraulic brake line.

[john881000]

been around to vw mates
asked if any known problems
also said after what you changed look at flexi hoses

they might appear ok on outside....but inside they collapse allowing fluid to go to caliper but stops/restricts flow back causing brakes to lockon/bind


hope this helps
cheers
john

[martin richards]

Thankyou all for your responses. I shall replace the hoses. Thanks again and shows all that this forum is worth its weight in gold.
Merry Christmas all
Martin.

[martin richards]

Hmm, cant get brakes to bleed. Seems like, once i opened up the system by changing the hose theres now no pressure. This did this when i changed the caliper and thought strange! It did eventually bleed and used the car for 100miles and then it siezed so i changed the master cylinder and she bleed in seconds. But now seems again no pressure? Shall split down system and have a look> Anythoughts??

[4WheelDrifter]

Did you bleed the system with the engine running, or do you have Vag-Com?
I know on the A3 I have to pressure bleed it with the engine running, or air gets trapped in the ABS unit.

[Dan_s2_coupe]

how are u bleeding the brakes with a 1 man kit or with 2 people

[martin richards]

I have tried to bleed with engine on and off. I believe this system, requires bleeding engine off, but i was at it for 2 hours. And this was only front OS. Was using 2 man technique. Can obtain 1 man kit 2morrow and try again? I would be surprised that my system is that different to your A3 (4wheeldrifter). How too pressure bleed?
Thanks.

[BRY]

Get an easybleed (sp) kit from Halfords. It uses the pressure from your spare tyre.
An essential piece of kit.

[martin richards]

yea, just got one Bry, will try in the morrow. Thanks

[martin richards]

Ok. All not well!!
Just to recap.
1. Front OS caliper locks on- Caliper changed, was difficult to bleed, but did so eventually. 100 miles then.
2. Front OS locks again- change master cylider. Bleeds as should, all well 4k/5mths.
3. Front OS locks again- change flexible. wont bleed, has no pressure to FOS/RNS.
4. Use pressure kit. will bleed ROS and FNS, but no pressure to FOS and RNS?

When spinning wheels with car off the ground, NS front brake works fine and so OS rear.

Each time the front OS locked up, i just waited for the caliper to cool down and unlock itself before driving home with brakes working fine.
So before the last time i disturbed the brakes, we had full pressure and braking force to all wheels?
This must be something else. As i have now no pressure to front offside and rear nearside at all, calipers will not move. Pressure kit on, and caliper nipples completley off there is no fluid coming out?

Do I have:
A. Fault master cylinder again. mine must still be under warrenty!!
B. Faulty Servo. but then all brakes would not work?
c. faulty ABS. which i hope not as a new unit will right the car off, with the cost to get sorted.
D. Something else i'm missing??

Sorry to keep bugging all. Thanks. Martin

[martin richards]

Problem solved. The route of the locking on problem was the flexible. However, by bleeding the brakes the 4 month old master cylinder was damaged, because during two-man bleeding operation we had pushed the pedal to far down to the floor, therefor damaging the master cylinder. This is according to VW not unheard of. So i shall be pressure bleeding from now on!! Thanks all.

[john881000]

good to hear all sorted