vacuum on 77 ford f100 HELP

just-n-time · #1 (**permalink**) 07-02-2008, 05:14 PM

high gang I have run into a little trouble with hooking up my vacuum lines on the engine, first I have removed the power brakes so we no longer need that hook up, but I cant for the life of me remember if it is a simple T fitting in the line from engine to vacuum canister or dose it have a one way valve too? Thanks for the help in advance JNT. TAKE PICTURE NEXT TIME or GET A BETTER MEMORY>

fmc400 · #2 (**permalink**) 07-02-2008, 06:45 PM

What vacuum canister? Do you mean the coffee-can looking one? Also what engine are you working on? Need more info.

just-n-time · #3 (**permalink**) 07-02-2008, 10:08 PM

yes the coffee can, did not know that there was another! its a 351 W with one vacuum line to the canester I was thinking that it goes from the engine to the controll head in the dash then out to the (coffee can) but I just can't remember. thank you JNT

fmc400 · #4 (**permalink**) 07-03-2008, 09:03 AM

The can is called a vacuum reservoir, it is used to help keep the heater controls functioning at periods of low vacuum, since the air duct system is completely vacuum-controlled. Both the vacuum reservoir and the heater controls connect to manifold vacuum. You can set that up however is convenient (T fitting like you mentioned), but you need a one-way check valve downstream of the reservoir. This keeps it from dumping out. My setup came stock with a 3-port check valve - manifold vacuum and the heater controls connect to one side, and the reservoir connects to the other side.

just-n-time · #5 (**permalink**) 07-03-2008, 02:24 PM

OK i WAS THINKING i NEEDED A CHECK VALVE but the other trucks I have have had the power plants pulled out so I only had one to look at and it was a fire case, though it had a plastic reservoir with two hose connections and some one threw a can type in it after the fire, so I am kind of in limbo here. thank you for your help JNT.