Brake Imbalance - Load Compensators

[ORB 227 1 Cars]

I have a brake imbalance on the rear axle (shown up at MOT) - I have not yet inspected but I have a feeling its faulty compensators?

 

I have the ABS type on my car, and was wondering if they are serviceable or more to the point how you go about working on them or indeed checking them for functionality?

 

What I am trying to say is how do I see if they are broken or not? and if they are can they be repaired or not?

 

Ta

 

PS - for the record the report says - RBT Brake Imbalance - 19% and 34%

 

does that tell you anything?

[welshpug 1,655]

they are adjustable, have a look.

 

is the handbrake in balance ok?

[ORB 227 1 Cars]

I think the handbrake was ok, I rang the tester today and he said it was the foot brake. From those readings, what one would you say is down?

[welshpug 1,655]

no idea, you need to get it on the roller again and see, then have a fiddle with the actuating rod.

[ORB 227 1 Cars]

Ok, cool, so they are not knackered as a rule they need adjusting.

[ablister 31]

they are adjustable, have a look.

 

is the handbrake in balance ok?

handbrake is not tested for an imbalance for MOT, just for an overall performance.

[commievid 8]

Apologies for the revival, but I had my MoT fail this morning on exactly this same issue, mine was:

 

RBT Brake Imbalance - 19% and 32%

 

So I've spent the last few hours looking at them. They appear to work on a spring loaded hinge which was sticking on one side (they should retract rearwards when pushed forward), so some plus gas and scrubbing has appeared to free it up.

 

Retest is in an hour, so we shall see if that has helped. Out of ideas if not.

[welshpug 1,655]

they may need adjustment if that doesn't cure it, however was the handbrake ok? I know the balance of that is not part of the test iirc, but they'll still see it I think

[ORB 227 1 Cars]

I'll be interested to see what the outcome is

[commievid 8]

It passed, but barely; RBT Brake Imbalance - 7% and 30%, so it did something, not sure what!

 

Adjustments sound the next step, I see a nut on the end where the large spring is, but there's no way to tell is there? What do I adjust it to, etc.

 

Handbrake cables are new, and the calipers are refurbs, but that still doesn't discount them I guess. I could easily have screwed up something somewhere. I loosened the handbrake cables in case they were the cause, can't tell either way if that helped.

 

Standard 1.9 compensators may be the only route, which I'm not up for attempting right now.

[commievid 8]

Went to Gloucester today to pick up a bonnet, and with a bit of rain was possible to give the brakes a good booting and to listen to which corner was locking up.

 

Not scientific, but it felt the N/S/R was locking up, so I got a 13mm ratchet spanner (was in the car due to adjusting the handbrake cable) and gave the passenger side compensator a couple of turns clockwise on the nut on the end of the bit with the spring.

 

That seemed to help, as the car was not locking up and the car was squirming in the other direction. My guess is that some more sophisticated means are required for something more precise, and that it feels like the driver side compensator simply isn't able to increase brake pressure compared to the passenger side, so tightening the passenger side reduces the brake pressure (makes sense to me, as it locking must have meant it was getting more power than perhaps needed).

 

I'm getting other braking issues (inconsistent brake pedal travel and a possible sticking N/S/F) so it looks like I'm not out of the woods brake-wise yet.

[ORB 227 1 Cars]

Weirdly, my car passed its Mot on Tuesday, all I did was new pads, strip & rebuild the rear calipers, lube up and work the stupid abs compensators and put a new flexi on the NSF caliper. Now the car pulls to the left under medium to hard braking

[Anthony 1,002]

I'm getting other braking issues (inconsistent brake pedal travel and a possible sticking N/S/F) so it looks like I'm not out of the woods brake-wise yet.

How old is your master cylinder? Inconsistent pedal travel and random pedal drop is one of the classic warning signs of immending MC failure, which as anyone that's had it happen will confirm, is not a nice experience.

 

If there is any doubt about the MC, replace it - new ones really aren't much money, and it's unquestionably worth it given the resulting sudden and unpredictable complete brake failure that can happen when the MC fails.

 

Any original MC on a 205 I would not personally trust, even if they appear to work fine.

[commievid 8]

The MC has been changed actually because of this pedal feel.

 

Before, it would occasionally sink whilst pressed at red lights, where subsequent releasing and pressing would then restore brake feel. Thus MC was changed.

 

Of course, I bought something cheap off eBay which could have been the cause, could also be the possibility I may have not bled it thoroughly or correctly, or even bodged something up whilst bleeding it.

 

It kind of switches from being really firm to then needing to be pressed a little before more brake force is applied, feeling more like a modern car. When it's firm, it almost feels like the MC is not being assisted by the servo, but I've only had the car back on the road a fortnight, so don't want to be doing anymore, hoping it won't lead to anything more serious of course.