IROCZ1989

iTrader: (1)

Have a fully assembled system on an 89 camaro with the 9 bolt rear pbr calipers. Redid all my lines with conifer from fedhill. All calipers are new, lines are all new because of the special routing on the UMI k member and 9 inch rear. Only thing I reused was the prop amd the Goodridge braided lines. I put in a roll control after the prop valve for nhra spec. I blocked the bottom outlet to the front brakes and used the other to go through the line lock and then split it to the two front brakes. Having issues with the bleeding of the system. Here is the problem. New master was bench bleed 3 times so I know no air is in that. New brake booster. Peddle is hard as anything until vacume is applied to the canister then the pedal goes right to the floor with zero resistance until the vacume is depleted. Pressure bleed, vacume bleed and two man bled. No air from any bleeders. The one issue that has me thinking is the prop valve. When I removed the bleeder that I was using to plug that one outlet nothing came out of the outlet, until I pressed the peddle. The other side that I have plumbed to the tee and though the line lock bleeds no issue what so ever. My plan was to plumb the plugged out to the line lock to get it back in the system. Is the prop the issue or the plumbing? Me bypassing that out maybe caused my issues? I noticed air in that line when I tried to bleed it. At a loss here. Thanks to anyone with imput on this.

Denis.V

What means

"master was bench bleed 3 times" ?

3 "pumps" only or 3 complete bleeds procedures ?

This could be the start point for review and checking

IROCZ1989

iTrader: (1)

I bench bled it. Installed it same pedal to floor when vacume applied. Rinse and repeat 2 more times. Zero air bubbles all three times. But a search here says air in the master with my symptoms.

Johnny Gun

My have a tear in the plungers seal on the master cylinder. Mine did that once.

QwkTrip

iTrader: (22)

The stock prop valve has a balance bar (or whatever it's called) that gets shoved to one side when there is unequal pressure between the front & rear brake line inlets to prop valve (from master cylinder). Did you go through procedure to center that balance bar? If not, then the front brakes might be partially blocked off.

Sometimes it can be a son of a gun to get fluid moving in a dry system. I tend to open the brake bleeders and let the system just sit for a while and let gravity do it's thing. Seems to help a lot with getting things moving. Pump out all that fluid of course, it's been contaminated with moisture from being exposed to air. And don't let the master go empty or you're screwed and have to bench bleed all over again.

IROCZ1989

iTrader: (1)

I have fluid at every bleeder no air. Whats the procedure to reset the prop valve?

IROCZ1989

iTrader: (1)

its a brand new master cylinder. I hope its not.

IROCZ1989

iTrader: (1)

Going to bump this up because I can't find the procedure to reset the prop valve, even if thats it

Beeman

Generally to reset the brake combination valve after repairs is to stomp on the pedal. The pressure on both sides will center the valve.
Let's start at the very beginning. But 2 brass plus that fit the MC. Plug the MC and see how the pedal feels. If it's hard MC is fine and there is no air. Proceed downstream from there isolating frt. from back and see what you get.
What MC? What size bore? Your MC might not have enough volume as the bore size might be too small for disc calipers you used.