My truck has an exhaust brake on it, but i cant get a name off of it. It has 2 vacuum lines ran to a solenoid block, with a toggle in the truck, and a switch mounted on the IP. I need a few pointers with this system. Is it power from battery to toggle in truck, to on/off switch on IP, to vacuum solenoid block?

I asked this in the Hi-po section, but i dont think there are any 1st gen's over there.

 

The toggle in the truck is probably an on/off switch for the whole system. The switch on the IP should get power when the toggle switch is on, and when the throttle lever is at idle there should be power to the solenoid.

If the power situation is good, check to make sure the brake isn't rusted open. You ought to be able to disconnect the linkage from the vacuum can and be able to wiggle the flapper valve freely. If not use some penetrating lube on it to get it working.

If it's not stuck, bypass the solenoid valve with a short piece of tubing and see if the brake will close. If the vacuum pump is making vacuum, and there are no leaks in the vacuum can on the brake, it should close.

My guess is it's just stuck.

 

or the solenoid is bad. There is a test switch to activate the brake you can push in on the solenoid. Is the canister on the brake silver?

 

yes the canister is silver colored. Reason im asking about the electric side is because while doing my timing, I noticed the wires going to the IP switch, wre not hooked up, and it looked like they shorted out at some point. I also have a lighted toggle and the light isnt coming on, so im looking to start pinpointing from the source. I havent tried to move it yet, maybe ill try that and add a vacuum source, then ill know if its a vacuum,mechanical, or electrical problem

Thanks