Scrounger said:
The standard 105 brakes, this applies to the one with one air line. When one applies the brakes air is fed from the service air line, can be painted yellow or blue, goes to a diaphragm that is connect to a rod that in turn operates the hydraulic master cylinder.
From that point it is just like any other hydraulic system with wheel cylinders and brake shoes. If the brakes aren’t working when air is supplied first check the fluid level in the master cylinder. The other thing is the brakes may need to be bled. If that doesn’t work the diaphragm may be bad. If it is one should hear an air leak when the brakes are applied.
The parking brakes are mechanical.
The truck that I plan on towing with is an IFA W50. The brakes wil not work until sufficient air pressure has built up. When applying the brakes, air pressure is released, and the brakes enage. This seems to be opposite function of what you are saying. In other words, if I lose air pressure, the brakes start to automatically engage. This would seem to be a safety thing. The glad hand in the back of the IFA has a valve. When it is on, air flows through all the time, then when the brake pedal is applied in the cab, the air to that glad hand is immediately cut off.
Does it look like the trailer and truck brake systems are opposite?
I assume that the trailer can't work the same way as the truck, otherwise I could not have towed it home from GL with my Chevy. I guess if it worked as the IFA did, the brakes would have been locked.
Any thoughts?
