77 c10 power brake conversaion question

[77c10]

I am in the process of swapping my truck to power brakes. Here is where I am so far.

Bought used booster and m/c, installed and plumbed, had to buy adapters cause the lines were reversed on the power m/c from what the were on the non power unit. Engine would not idle. Figured out the booster was bad and was creating a huge vacuum leak.

Bought 2nd booster and picked up a new m/c. Bench bled the m/c and installed it using the adapters mentioned above. I started the truck, it idled fine but no matter how much I pump I can not get the pedal to pump up.
The m/c seemed to work fine while I had it on the bench bleeding it.

Any ideas where I should start?

[77c10]

I am leaning towards the rod between the brake pedal and the back of the master cylinder not being long enough. Anyone ever had a problem like this? I plan to go home tonight and take the top of the master cylinder off and have my son pump the brakes and see if I see anything happening.

I also wonder if it would have anything to do with having a non-power brake pedal?

[burb1085]

Maybe you got ahold of another bad booster. Could also be air still in the lines.

[burb1085]

there's a diagram on one of the chevy forums try to goggle brake diagrams, should be able to find out what size the rod is.