Brake performance poor

Paulcovy

Member
hi all when I've been driving my p6 I've notice the brakes arnt very good the pedal feels very wooden and it seems to lock up easily .. I'm convinced there not ment to be like that and if someone were to pull out on me I would never stop in time .... All the friction materials are good and all the brakes have been bled ... Has anyone had a similar experience and what's the best way to go about finding the problems
 
the pedal feels very wooden and it seems to lock up easily ..

The first half of the above sounds like the servo not working, but that would tend to be in conflict with the second half of what you say. Without the servo effect it's a lot more difficult to lock the wheels up.


I'm convinced there not ment to be like that and if someone were to pull out on me I would never stop in time ....

That again sounds like the servo not working.
 
I agree with Harvey that your description of the symptoms sounds contradicting.
However, trying to interpret it in a different way, what you describe as "wooden" feel may well be due to hard components on the brake pads. So, have you noticed if the feel improves at all when the brakes are hot?
The easy lock up could also be due to old / hard / rubbish tyres. The tyres can cause a world of difference on how a car stops.
 
I think your on to something with the servo ... I think maybe it locks up because I'm having to put more force than necessary....should I get a rebuild let for the servo?
 
Hi Paul,
Rebuild kits are available but you will need to inspect servo cylinder bore very carefully for corrosion/ pitting.
Not many of these are reusable now unless stainless steel sleeved, and require careful re assembling
as can be a bit temperamental for sticking /slow releasing of brakes when hot..
Mark Grey of MGBD can offer rebuilt units if you don't want to do it yourself.
Clive.
 
Thanks ... I like to have a bosh at things myself If possible ... How hard is it to sleeve the old unit
 
A very basic test of the servo is to sit in the car, push the brake pedal down firmly, then start the car. The pedal should drop an inch or so. If it doesn't then the servo has a fault.

Richard
 
Update.... Took the vacuum unit off the top of the servo today and found the little piston that acts on the air valve diaphragm is seized and someone has beaten a flat head screw driver into it by the looks of it ....
 
Not good news. The main bore is easily sleevable, that small bore for the reaction piston not so easy. I think I'd just spring for a rebuilt unit at this point.

Yours
Vern
 
You can free most things off but that small retraction valve is notorious when worn to completely empty the brake reservoir and fill servo casing with brake fluid leading to NO brakes at all.
Just be very careful when cylinder bores are inspected /no scoring or pitting at all or it's not safe.
Good luck.
Clive
 
Thanks took it apart this evening the bore looks good .... I think the rubber seal has swolen as the only marks in the bore where tiny pieces of rubber which have cleaned off nicely
 
Back
Top