Air brakes

[Joaquin Suave]

I like to get $.02 from you guys...

When i re-motor Casa Azul (F700 Ford 4x4) I'm thinking of removing the "hydraulic over hydraulic" brakes and fitting her with air brakes.

I have been given the air brake system off of a cab forward semi and figure that I can find an F800 in a junk yard for the remaining "cab specific" components that i don't already have.

 

[Trango]

Wait, do you have "air over hydraulic" already?

The hard part will be, as I'm sure you're aware, the front axle.

 

[Trango]

By the way, and this is actually somewhat counter intuitive, but with air brakes, despite all the benefits, you do get lockup under about 35psi.

 

[Joaquin Suave]

The brake system is currently a dual circuit hydraulic system with a hydralic booster system (engine driven like a powerstearing pump).

I think that I can get the specific mounting components to mount the air slave onto my front hubs. If not I can make them ( I own a 5 axis cnc machine shop).

but with air brakes, despite all the benefits, you do get lockup under about 35psi.

I don't understand?

 

[Jones]

Should be able to get air pots from a later front axle of the same type that'll bolt in. S-cam is what everything has gone to and parts are all over the place. Air brake components either work or they don't; no user adjustments or fixes but everything is cheap enough that you just swap out bad for good and send the valve, pot, whatever in for rebuild.
Lock up under 35 psi? probably talking about spring brake rears that self apply if the air drops too low so you done have a runaway. Air pressure holds them released. No air and the internal springs apply them for you. Only way to move the vehicle is to regain your air or "cage" the springs with the caging tool. Don't take a spring brake cylinder apart to see what makes it work; there's a very large, very mean spring inside just itching to get out.
PM me and I'll get some Bendix brake info off to you to help you lay out what you need.