Rear Brakes Efficiency

[KennyW]

Hi All,

As a follow on to my Mot posting, I'm wanting to nail this problem.

What things can affect the effectiveness of the braking.

Obviously the usual things

Pads, Discs, worn calipers, alignment, sticky pistons,anti sink sphere leaking, is there anything else I'm missing. As it's strange it has been the same problem the last 2 MOT's.

I'm going to be changing the 3 spheres on the rear and dong a hydroflush.

Any thoughts or suggestions

Kenny

PS When I spoke to MOT man, he has not been told what the changes are coming up but he thinks the efficiencies are to be set higher but he thinks it will be age dependent.

[longgo]

Have you try to put some heavy bag(50-60kg or even 100) in the trunk before the MOT test?
Because the breaks takes power from rear corrector, and if there is no load the back breaks almost not work.. If the mot guy have no idea of citroen with hydraulics..here is the story

[RichardW]

MOT Changes: detailed here

Some affect all vehicles (imbalance), efficiencies only post 09/2010 cars.

Someone else posted here that adding weight to the car makes no difference as the rollers compensate for the weight on the axle. When I have seem mine tested it achieved lock up at the rear, so something is amiss with yours Kenny!

[xantia_v6]

My advice would be to fit a new set of pads. If you know what brand of pads is on there now, then buy something different, otherwise go for OE pads, or Mintex or Ferodo or something else which is likely to have a good friction coefficient. Stay away from "performance" pads which are designed to work well when very hot - the MOT test is invariably done with cold brakes.

[KennyW]

Thanks guys for the replies, my previous Xantia 1.9TD estate never had this problem.
The only difference between the 2 are 2.0 Hdi 90hp estate with ABS and 1.9TD estate without ABS.
I felt there was an improvement after I checked them over. The figures from the rolling road were higher all round.

Kenny

[longgo]

My bet is that already is old topic but.. anyway - bleeding the rear breaks will improve breaking way. Well friend of mine give me following tip, that maybe can help you and others also: here is his working way - lift car, put stands(rear), remove wheels and put on low position. Then under rear arms put some wooden blocks or plastic or.. rubber but not metal in that way that when you put on normal level position the car will touch them and wait until stabilize. Then bleed. All that on running engine and hand break pulled to the max. Believe or not that do it better than max level bleeding. Then when you break the whole car "sit down" when push the break pedal not lifting the ass or so, and all MOT test are passed well.