Brake problem

[ThomasTedder]

I got this 82 C20 after it was sitting in a field since 1997. The brakes on the right side both worked and the one on the left side weren't. I put on a new master cylinder, left front caliper, and left rear wheel cylinder. The left rear brake bled fine, but I cannot bleed the left front brake. I have a vacuum bleeder and I still cannot get any fluid through the left front. I separated the hose from the new caliper and I cannot suck fluid through the hose either. Pushing the brake will not squirt any fluid out of the hose. I know the master cylinder isn't bad, because the right front brake works. I cannot remove the brake line without destroying it so I need to know if the Combination valve can cause a problem like this before I assume the hose is plugged. I read in the book that the combo valve won't engage the front brakes until there is enough pressure on the back brakes, but I know the back brakes work (they will squall the tires). The book also says to depress a pin on the combo valve when bleeding. I had someone press the brakes while I held the pin. I was watching the dangling hose and nothing still comes out. All that happens is the pin stabs my finger. I even used a steel wrench to hold the pin and still nothing will come out of the hose.

So am I looking at a bad combination valve or a plugged hose?


Here's a pic. The camo is what sold me on it.