Hi everyone
I have a 1991 f250 4x4 with the 5.8 v8. i was replacing my valve cover gaskets and removed most of the vaccum lines to find that they were mostly broken or very brittle and broke when i removed them. I am wanting/needing to replace them. I was wondering if anyone had any diagrams or pictures of the routing so i could redo them correctly. Also this is my first project that has a lot of them and all of the newer components so any description of the various valves and switches would be nice as well. I know there is a small diagram under the hood but since i don't know where most of the components are that it says it's not to helpful. Thanks in advance. Also could this cause excessive smoke from the exhaust pipe? it's smoked since i got it but it looks to be much worse

 

You should have a sticker under the hood with the routing of most the vacuum lines.
The only ones not in the diagram are the vent vacuum routing and the speed control & brake booster.

If the sticker is missing post your Calibration number off the "B" pillar and we will try and post one for you.

The Calibration number in the below example is "4-54E-R10".


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i have the under the hood diagram but i dont really know what i'm looking at.

 

It show the routing of the vacuum lines, their source and their colors.
It shows how the vacuum lines are hooked to all of the emission solenoids and their actuators, fuel pressure regulator, map sensor and the vacuum tank(s).

The only ones not in the diagram are the vent vacuum routing and the speed control & brake booster vacuum lines/hoses.

 

Ok. I'll look at it some more and see what i can figure out. I just need to replace the small colored ones

 

I have replaced all my lines because I kept having too much trouble with the older lines breaking and cracking. I bought some silicone tubing (like they have at siliconeintakes.com) and it has worked well so far. You may need to do some repairs if you push and pull too many things.