Hey Folks...
I've been re-doing the brakes on the 79 I just got and ran into a problem. When I got the truck it looked as if someone had poured dirty fluid back into the master cylinder...which probably was cause it went out a couple days after getting it home, plus one of the calipers went haywire too...replaced everything on the front, bled,the front only so far...and have brakes..but it feels like the front brakes are doing most, if not all the stopping. The thing is before the MC went out the brakes seem to stop the truck fine. Well today I was gonna bleed the back brakes and see if that made any difference...well my dad got in, pumped, held, I released the bleeder valve..and nothing. Pedal never did move towards the floor, even after backing the bleeder about halfway out. There wasn't any sign of leakage around either wheel cylinder and was hoping I could get by right now without replacing them too.
Any ideas as to why they won't bleed?

 

Ok...may have it figured out...proportioning valve...fun tomorrow, heh.

 

Finally found a 78 in a junkyard and got my brakes working good..need to go back when I have the money and get the original air breather housing for it.