cnc brake pedal bleeding problems

outhouse · Jan 3, 2010

i started by bleeding the rear and it went very well no problems. i went to the front and am not able to get them bleed. i used a vacuum bleeder to start them then the usual pump and bleed so forth. i pump and pump and the front calipers are tight then they loosen up amedeatly. i tore the master apart and the o ring is fine, it all looks good. and there is not much pressure at the bleeder. any help would be great. and there is no air when i bleed it.

Not Jobless · Jan 3, 2010

Brake line restriction...?

ain'tstuckjustresting · Jan 3, 2010

Are the calipers on the correct side? I've seen people put 'em on w/ the bleeders on the bottom and you can't bleed 'em.
Not insulting your skills just starting easy..............

outhouse · Jan 3, 2010

Puss-N-boots said:
Brake line restriction...?

nope there are no restrictions, me and chris (red beard) checked all the lines.

ain'tstuckjustresting said:
Are the calipers on the correct side? I've seen people put 'em on w/ the bleeders on the bottom and you can't bleed 'em.
Not insulting your skills just starting easy..............

no there on the rite sides, bleeders on the top.

i went on cnc's web site and it said not to pump the brakes just hold the pedal bleed it, wait 5 sec. and do it again, i went and tried that and same thing, its like theres a huge vacuum pocket in it but i cant get it out. i worked on it for 3 hours today just bleeding. no air just fluid. and the pedal is a remote res. master so theres bleeders on the brakes and iv tryed bleeding it there first but still no good.

Ed Bister · Jan 4, 2010

outhouse said:
nope there are no restrictions, me and chris (red beard) checked all the lines.

no there on the rite sides, bleeders on the top.

i went on cnc's web site and it said not to pump the brakes just hold the pedal bleed it, wait 5 sec. and do it again, i went and tried that and same thing, its like theres a huge vacuum pocket in it but i cant get it out. i worked on it for 3 hours today just bleeding. no air just fluid. and the pedal is a remote res. master so theres bleeders on the brakes and iv tryed bleeding it there first but still no good.

Ive had this same problem....... try bleeding by cracking the brake lines from the top by the master to the connection at the calipers. then bleed them like normal....sometimes this will help get you started.

Good luck!:beer:

Clark · Jan 4, 2010

silly question, did you bench bleed the masters before putting them in and bleeding the entire system?

outhouse · Jan 4, 2010

i bleed the masters before i bleed the calipers, but what do you mean by bench bleeding them?

Clark · Jan 4, 2010

Fill the Master with brake fluid, then run the brake line back into the reservoir. Then pump the master one stroke at a time, with a 5-10 second pause between strokes. Once no more air bubbles come out of the line, it's bled, and ready to install, and connect your lines, then bleed the lines and calipers like you would any other time.

It's reccomended on any new master cylinder before installing it. Somtimes you can get away without doing it, but sometimes not.

have you tried pinching all your brake lines then seeing if you have a good pedal? That would tell you if your problem was the at MC or the calipers.

here's a link to a yutube video demonstrating the basic technique. some people do this on their workbench, that's where the name comes from.
http://www.youtube.com/watch?v=i3Jhbz4mVKw

Ed Bister · Jan 4, 2010

ClarkW said:
Fill the Master with brake fluid, then run the brake line back into the reservoir. Then pump the master one stroke at a time, with a 5-10 second pause between strokes. Once no more air bubbles come out of the line, it's bled, and ready to install, and connect your lines, then bleed the lines and calipers like you would any other time.

It's reccomended on any new master cylinder before installing it. Somtimes you can get away without doing it, but sometimes not.

have you tried pinching all your brake lines then seeing if you have a good pedal? That would tell you if your problem was the at MC or the calipers.

here's a link to a yutube video demonstrating the basic technique. some people do this on their workbench, that's where the name comes from.
http://www.youtube.com/watch?v=i3Jhbz4mVKw

x2 your master should have came with bench bleeding instructions and hoses. i have lots of extras if you need some. i'm in auburn:awesomework:

outhouse · Jan 4, 2010

ClarkW said:
Fill the Master with brake fluid, then run the brake line back into the reservoir. Then pump the master one stroke at a time, with a 5-10 second pause between strokes. Once no more air bubbles come out of the line, it's bled, and ready to install, and connect your lines, then bleed the lines and calipers like you would any other time.

It's reccomended on any new master cylinder before installing it. Somtimes you can get away without doing it, but sometimes not.

have you tried pinching all your brake lines then seeing if you have a good pedal? That would tell you if your problem was the at MC or the calipers.

here's a link to a yutube video demonstrating the basic technique. some people do this on their workbench, that's where the name comes from.
http://www.youtube.com/watch?v=i3Jhbz4mVKw[/QUOTE

cool thanks, my maser cylinder didnt come with those hoses but im guessing they have them at a auto parts store? any ways thanks guys ill give it a try let ya know how it works.