1976 K100 Cabover project

I think that might be the wire that gave trouble.

 

I’ve seen a lot of wires like that on 70’s model trucks running under cabs and in frames. Is it 12-14 ga. with thick wall harder plastic insulation that makes it the size of an 8ga.?
They used that type of wire for the old gooberment mandated 121 “anti-skid” brake systems that they ultimately recalled, snipped the wires, and removed the boxes that were mounted to the frames near the drives. The wires were rarely removed from harnesses.

 

If you look at the axle flanges or (backing plates if you have them) on backside of brakes on drives you may see a snipped wire that looks like that barely sticking out unless someone took the time to completely remove them. They went to a wheel sensor ring. I have rear housings from a ‘74 in a truck that still has them visible.

 

If you pull the hand valve down do you have air coming out of the blue line?

 

So when on peddle only they blow air?

 

Ok. I see the hoses now. Thought you said wires. Someone may have “borrowed” the tractor protection valve or maybe even the air dryer if it had one.
If it builds and holds pressure it won’t be a missing dryer.
If it only blows down air with the peddel or hand valve applied I would think someone removed the protection valve.

 

Sadly. Perfectly good sitting trucks often times become parts trucks.