Vacuum line on heater box
 

1993 f350 IDI no turbo 7.3 5 speed std. Shift. On top of heater box all the way to right next to firewall under hood there is a vacuum motor with no vacuum line at all I think it is the fresh air flapper. Is there someway to figure out where does it go? Thanks:s:

---AutoMerged DoublePost---

It don't show anywhere in the book

MOTORCRAFT YH-1463 Vacuum Motor

The motor looks good, it is just the line to it. It looks like I will have to pull the dash front and trace it.

There should be a plastic tee that it plugs in to, should be right behind the ac actuator I believe it's called, it's a very thin black vacuum line that holes it, the line itself is white coming from the actuator that I showed you

Thanks I check that, this problem is on my list this weekend, even if I have to pull dash and at the same time I'm changing heater core. So I won't have to later.

That motor is what makes the MAX A/C option on your HVAC controls work. It's supposed to isolate the heater core from the rest of the box. The hose probably got brittle from heat and time and broke off. When I installed the heater core bypass valve on my truck, that hose crumbled in my hand when I removed it. I was able to chase it back a bit to where it was still good and connect another hose to it.