I'm driving a 1989 F-150 with a 5.0L 4x2 with AC.

I just recently had it serviced, but what I didn't know was that the mechanic had forgotten to replace the radiator cap. I then drove about 20 miles back home. When I parked the truck, I opened the hood because I smelled coolant, and found the cap off. Thankfully most of the fluid ended up in the overflow tank. I top everything back off, and when I went to use it the next day, I noticed there was no heat at all. I thought I may have gotten air in the system, but it doesn't appear that was the problem.

I did happen to notice that the thin white vaccum line that runs from the valve on top of my heater unit is broken. Is that the valve that controls the hot and cold air mixture? And if so, what is it called and where can I buy it? Thanks ahead for any help.

 

i think that white vacuum line controls the heater door. if its too brittle then you should replace it. but you can just use a piece of rubber vacuum hose and sleeve it.

 

That's the recirculate door motor. The temperature blend door is cable-operated on all '80-96. Inspect the heater hoses & make sure they're connected normally. Then recheck the coolant level.

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