Bleeding brakes Bx

Niek · Unread post by **Niek** » 17 Jan 2003, 14:56

Hi people,
I have a silly little question. I've had Bxs for about 2,5 years, and I've never had to bleed the front brakes. The other day I felt I was having some problems with the brakes and wanted to bleed the whole system. The rear brakes no problem, no really, not even the nipples <img src=icon_smile_big.gif border=0 align=middle>. There was some air in the pipes, but then again I had, not long before, replaced the two rear spheres. I realised after doing the rear that I had no clue about the front. I couldn't find the damn nipples so couldn't bleed them, same goes for the brake valve. Is it bleedable(??)? The Haynes comic mentions a 'calibration' bolt which I have located, what does it do?
I'd appreciate it if someone could clear this up for me.
Niek.

alexx · Unread post by **alexx** » 17 Jan 2003, 16:54

Look again, there ARE bleeding nipples on the front brakes.
There are two types of brake valve. First one, 2-slide valve, has bleeding nipple. Latter one, 3-slide valve ("XM-type"), doesn't have one, but is fitted with calibration bolt. It's not for bleeding, but for a sort of rear brake circuit calibration.

Niek · Unread post by **Niek** » 17 Jan 2003, 17:54

Has anyone ever played around with the calibration bolt? What happens?
Alexx do you have any clues as to where those nipples should be on the caliper? Do you have to remove de deflection shield?
Niek

alexx · Unread post by **alexx** » 17 Jan 2003, 18:11

From the brake valve picture, calibration bolt seems to be there to set the flow of LHM to rear brakes, when the brake pedal is pressed. Maybe it's to set a little delay - when will rear brakes start to brake after front ones, to improve car stability when breaking. I don't think someone ever played with it.
I was there when my mechanic once bleeded front brakes. As I remember, he didn't take off anything, except the wheels. But don't remember the exact location, it was about 4 years ago. Somewhere on the upper side of the caliper they must be.

philcut · Unread post by **philcut** » 18 Jan 2003, 03:18

try this link-http://www.bx.citroen.org/m21/m21.html
I know it's in Japanese,but most of the pictures show the bleed nipple.It's under the little rubber flap right by the attachment point for the handbrake cable.<img src=icon_smile.gif border=0 align=middle>