I have a 1988 F-250 with a 7.3 idi naturally aspirated. I'm owner number 6 and the previous 5 screwed this thing up. There are a lot of lines in general that got cut. The vacuum system is just dry rotted and old. Its got some vacuum issues, but it still runs and drives. I started to pull lines, and me being an idiot, didn't take pictures or a video

I was wondering if anyone had a vacuum diagram for a naturally aspirated 7.3.

Thanks

 

there are really only two things that need vacuum. the brake power booster, and the ac/heat controls.
well, three if you have a C-6 trans. the trans modulator needs vacuum to shift.

 

I know. I haven't solved the tree for it. A few lines were literally dry rotted off of it. I don't know what is supposed to run where.

 

it really don't make a difference where what line off what port on the tree goes.. as long as you have a small line to the heat/ac controls, a large line to the booster, and a small line to the VRV if it has a C-6 all will be good.

 

The factory vacuum tubes on these were not particularly elegant anyway, don't stress over it. Just work some rubber line from each component back to the tree. If your truck has cruise control, that will need it too. The reservoir goes between the tree and the servo.

Dunno if this is helpful or not, but here's the info from my 1992, First Printing, service manual- which covers the early '92 V-belt system, which AFAIK is the same or extremely similar to an '88.