I'm working on a mid 80's frieghtliner cab over and i'm hooking the air lines back up. I've gotten rid of the trailer supply and the tractor only air valves and i'm only using the parking brake yellow one. The front brakes work already with the foot pedal but the back dont. I have the lines coming from the valve to the maxi brakes hooked up correctly and i have a supply line from the tanks to both valves and the lines that are supposed to actuate the valves but i don't know if they are correct. What I need to know is does any one have a picture or schematic of the lines going into the foot pedal and where they go to or come from i have just the basic air line schematic from Bendix but that really isn't much help. also i don't even know if the parking brake works air gets to the valve and it purges when released but i dont see the maxi brake rod move.

By the way this truck is running a big cam cummins which has triple turbos and is fueled to the max. It's a project at the vo tech school i'm at and we need the brakes to work to move it around.

 

is it possible u guys got the air lines swapped at the champers? parking brake feeding normal side?

 

yeah im guessin even though you think you have the airlines at the chambers right you might have em backwards...happened to me a few times

 

i think i do, ive got the parking brake ran to the spring and the foot pedal running to service

 

will say this. add another parking brake valve, and put rear chambers on the steer axle. they u have a line lock! hahahah