Hi Guys.

Hope someone has a quick fix for this ! Mate's BX, '92 with ABS. Had occasion to change a front caliper / bled it at the relevant corner. When he first drove it, he felt the brakes were 'awful' compared to previously, with a hard pedal. I tried it and with a push they seemed fine to me. Took it for MOT and the tester picked out that the pedal initially felt hard, as though nothing happening, but would then give and the brakes work properly. On the rolling road, the caliper showed up fine, working and releasing as it should. So ---- have I upset the ABS -- a valve somewhere -- or something else ? The pedal wasn't touched while the caliper was off. All thoughts much appreciated.

Mike.

Hi sounds as though you left the brake pipe clamp on the flexy pipe , or has it closed up a bit due to twisting maybe .sounds like some sort of blockage or mechanical resistance
bst regards Bob.

Hi Mike

Have had similar problems with a Bendix ABS on an XM.
Does the ABS block need bleeding as well or does it sort itself out. XM Bendix ABS has a pair of screws for internal bleeding while the later Teves block self bleeds.

John

Hi Guys.

Thanks for the thoughts. I'm sort of hopeful I've found the issue ---- The pads are held in place with a miniature piece of angle iron and I think the one on the new caliper may have been slightly distorted, semi wedging the pads. Anyway, have changed it for the old piece, greased it all up, bled it again, just in case and to me, at least, they now feel fine.
I did wonder about the ABS and unlike the XM, the block is as accessible as you could wish on the BX, but absolutely no sign of any bleed provision. Oh well, will take it back to the test man on Monday and see if it is a result or not.

Mike.

I've changed plenty of these and never had any problems with the ABS. I'd suspect you are right with your fault finding.
Good luck.

Sounds like air in the brakes to me.... What air does in Citroens with proper high pressure hydraulic brakes is cause a time delay. The more air in the brakes the longer time delay..... So say for example you never get around to changing the brake accumulator on your CX ........ You'll be in for a hell of a shock when someday you hit the brakes ...... and nothing happens.... Due to the vast amounts of nitrogen now in the brakes due to a ruptured brake accumulator diaphram..... There will be a mmmmmmmmaaaaaasssssiiiivvvvveeee brake delay, by which time you'll be standing on the brake pedal in terror which trying to avoid what you intended to slow for ...... then suddenly all that air will compress and 'cos your standing on the brake pedal, next thing is your sliding along with the brakes fully locked Um, the sort of thing you only ever do one time .... Each time you touch the brakes while all that air is in there, you will have at least a 10second delay before the brakes apply.

It is critical you keep your brakes bleed well and immediately replace any suspect brake accumulators !

seeya,
Shane L.

There are quite a few comments about the "angle iron" causing problems on the Bx Forum Mike. Also the pad spring can cause problems (it says!)

that sounds like the fault on my old XM the peadal would ,very ocasionaly, go hard and then give way, leading to a skid??? never did sort it?