Poor brakes

[Defender110]

Another senior moment; I was trying to figure out why you needed to stuff a rubber ball in to stop the spring falling out in this picture, after studying it for some time I then realised it is your finger in a rubber glove

[citronut]

i wouldnt work out in the cold till my fingers ( well what i have left of them ) turned blue like those in the picy

regards malcolm

[citsncycles]

It was a long time ago but I do remember reading in a Citroenian that while Mk1's were like all previous Citroens with a hydraulic system with a direct acting brake pedal, Mk2's had 'artificial feel' built into them in an effort to make it feel more like a normal car.

[mat_fenwick]

That would fit with my limited observations, as the only Mk1 I've driven is Timex, and there was a marked difference between that and the late Mk2s I've more familiar with. It was that which prompted me to weld up where the spring sits! It still doesn't feel as sensitive as yours, which I've put down to the fact mine has ABS.

If the change to add the spring coincided with Mk2 introduction, it doesn't explain Dollywobbler's problem though...I'd wondered whether it was fitted only to late Mk2s, which would fit the symptoms if all his other BXs have been earlier (pre-spring) cars.

[Dollywobbler]

We'll see if we can find anything obvious on Friday. LHM is out for delivery tomorrow hopefully...

[MULLEY]

I suspect very old lhm sat in the dead stops of the calipers, so it overheats very quickly when braking, hence poor performance.

[mat_fenwick]

I can't see it being that TBH - why would it get any hotter just because it's old? And for it to get hot, first the pads have to get hot, then transfer that heat via the (deliberately) small contact area between the pads and pistons before transferring the heat to the fluid.

Hopefully we'll have more of a clue tomorrow!

[Dollywobbler]

I suspect very old lhm sat in the dead stops of the calipers, so it overheats very quickly when braking, hence poor performance.

I don't buy that. You're never going to generate enough heat with that first brake application of the day to cause that issue. I think the back end was bled when the rear arm bearings were done, as one brake pipe snapped. Therefore the only caliper with old LHM in it will be the nearside front.

We'll see what we find tomorrow. New accumulator and replacement pump available.

[MULLEY]

If you took the Heat argument out of the equation, Fresh LHM will have a certain amount of resistance as opposted to brown/yellow piss, the pistons don't receive as much pressure to them for the same amount of braking action? But air in the lines is also a potential factor, along with a hydraulic system that is down on pressure, its probably all 3 things tbh causing a cumalative effect of rubbish brakes. Fingers crossed you can solve it, as its rather important safety feature.

[citronut]

just try one thing at a time or you wont know for sure which fix fixed it

i would fit the new A/C sphere first but this in its self wont make much difference without bleeding the brakes as well

regards malcolm

[rutter123]

i think bleeding the whole braking system is a good idea as the lhm in the brake lines always stays in the brake lines and dosent recirculate back into the system does it? even when renewing the lhm in the reservoir unless you bleed all the brake lines the old fluid will remain in the brake lines, i found good quality pads a full brake line bleed and a new accumulator sphere, and new flexi front lines as the old ones were starting to "blow" under pressure improved the brakes on the tzdt 100%, also the rear calipers were starting to stick on slightly, get them pistons freed off and lubed. mind you dont break off any bleed valves as they do quite easily, i also replaced all these. new discs can also make a vast difference and can be obtained from ebay for peanuts, i paid about £30 for a full set front and rear. the brakes are now sharp and pull up evenly and smoothly and the pedal has a lot more feel to it with less pressure needed to brake.will be giving the tgd the same treatment soon as the brakes are ok but feel as the tzdt did beforehand.

[Defender110]

improved the brakes on the tzdt 100%, .

So you didn't have any brakes to start with then?

[rutter123]

meaning they are twice as good as they used to be-last MOT rears were only just meeting the req limit and front 23% imbalance on 1 side and only just meeting requirements, couple of hours overhaul well worth it.

[Tim Leech]

I need to get the brakes bled on the TZI, there is too much "sponge" in them for my likiing, the accumulator and rear spheres were flat as witches wotsits when I got so probably the nitrogen is flying around somewhere.

[citronut]

and new flexi front lines as the old ones were starting to "blow" under pressure

yep thats one i had forgotten about

regards malcolm