F600 '74 Need help, braked, head, water pump

[Black litening]

Hi All, looking for some help here, I have a 74 F 600 grain truck that I use for hauling construction material to the dump. Recently on my way back from the dump I slowed down at a stop light and I started rolling out white sweet smelling smoke from the exhaust, (which later quit and no longer does it) and at the same time my brakes went out. (Not sure on this brake system, I have a brake fluid resevior under the hood, and the master and booster are under the driver side of cab with an air tank further back. Also have a vent of some sort behind the seat that makes noises when I push the brake pedal...what kind of system is this? Air brakes, vacuum brakes, air actuated?????) Anyhow I found out after some investigating that my water pump ins't working...of corse the temp gauge doesn't work to warn me of this. I wonder if this is a fluke that my brakes went out at the same time this white smoke was coming out of the exhaust. The engine runs fine now (no water pump tho), but the brakes don't, it just pushes the pedel back when I push it with very limited stopping. Is it possible that since the water pump failed that the engine over heated, cracked the head, burnt the antifreeze that was in the engine(white smoke) and no longer created a vacum to power the brakes? Is that possible? It is the only theroy that I can come up with that makes sinse. All braked lines and hoses and everything looks normal, no leaks anywhere. Any help would be much appreciated. Thanks. Oh Is has a 1970 something mut for an engine...probably 330.

Sorry for this being a link but, it didn't let me post the first time and had it coppied on a clip board...only way to past it.

[unclebubbles]

The brake system on these trucks is called Hydrovac. It is a vacuum over hydraulic system similar to any vacuum assisted power brake system, with a few differences. Pressure from the slave cylinder on the firewall which is also the reservoir for the system, activates the master cyl/booster under the driver side floorboard , when you mash the brake pedal. The pedal kicking back at you is usually an indication of low vacuum, but could also be a problem with the booster. The fact that it did it after it ran hot could be from a vacuum line getting hot and collapsing/breaking. Check all the vacuum lines and check the vacuum at the booster end of the line. Also check your manifold vacuum to see if its up to spec. Booster vacuum should be the same as manifold(18-20"). If you ever have to bleed the system, bleed the master cyl/booster first before going to the wheels. And make sure you keep the slave cyl/reservoir full, watch it close. It doesnt hold much fluid, and that system moves alot of fluid with a full pedal stroke. If it runs out you`ll have to start all over. LOL Power bleeding is a good idea to prevent that.