brake going to the floor

Just replaced one caliper on my waggy 44 bleed all the lines pedal gets hard no air bubbles but as soon ad I start the truck pedal slowly goes to the floor. The truck does stop fine but soft pedal to the floor. Kept bleeding again no bubbles. Im lost on the pedal going to the floor still

 

ok so i thought maby my master was going bad. Since i was all ready dropping it the truck off at a shop i had them look at the brakes also. they said the master is good and bleed all the lines NO air, the tech said he thinks it could be my BPV ether out of adjustment or bad since the truck nose dives when braking. its like the rears are not braking. but how would this be affecting my pedal?

any ideas??

 

Bumping you since this is a safety concern.

 

Thanks. I don't get how the bpv would cause the brake pedal to be soft

 

How can I check if the bpv is working. Also going to check the and adjust the rear drums. But im thinking it could be the master.

 

Cmon guys help him out! I'm sorry I don't know anything about this but I'll try to help with the bumps so you can get some.

 

I have the EXACT same thing going on. gunna try to re-bleed all the lines tomorrow just to see if that does anything but help on this would be great!

Ekahi- I'll let ya know if I figure anything out

 

Could be the slave going out. Had a similiar issue and the master was fine - it was the slave that was bad.

 

So I re bleed every thing again completely no bubbles. With the truck off pedal gets hard and holds solid. But with the truck running there's some pressure but pedal still goes to the floor slowly. Thinking maby master or the rears some how need to be adjusted.

Also when I use the pumping the pedal method no bubbles at all. But if I use my hand pump im geting bubbles.its not leaking past the hose cuz when I close th bleeder no bubbles. Its like airs leaking past the bleed nut from the suction.

 

Never had a problem bleeding brakes its driving me crazy. Fyi the truck doesn't have abs. Didn't know there was a slave cylinder on the brakes. Your might be thinking of the clutch slave. Might try adjusting the rear drums.