I have a 1984 F150 with what I think is the V8 4X4 5.0 automatic.
The engine cranks up fine when cold. It does run a little rough and idle low, but will run. Once the engine is warm, i have had 2 experiences.
1) engine runs really rough and stalls if you do not keep on the gas. This has been when air temps have been pretty cold out.
2) Engine runs pretty smooth, but when you stop the engine it will not restart until it cools down. The cranking sounds very strong, just will not start. This was the case today when the air temp is around 55 degrees

I checked that the choke flap was fully open once warm (vertical)

One thing I noticed was a little liquid sitting in the reservior in the air cleaner housing that connects to the oil filler cap. It was smoking a bit also.

I do think I am leaking some antifreeze from somewhere if that is relevant...

Does anyone have any suggestions to this newbie to the F-150 world!
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do you have an electric choke? I ask because mine could be adjusted to start when warm on the first try, but not cold, when adjusted to start cold first try it would have to cool down before I could restart it. I got rid of the electric choke and put in a manual, never have any problems now regardless of temp.

 

Check for spark while cranking-not starting. This sounds very much like the famous ignition module starting to fail. They get hot, quit working, then cool down and work again-for a while.
Does this engine have the module on the dist (5-7 wires at dist and no vacuum advance) or the module on the fender (3-4 wires at dist and a vacuum advance). 1984 saw both systems used.

 

I do not see any kind of module on the driver side fender, though I do see a flat rectagular piece coming off the side of the distributor with a bunch of wires plugged in to it.

 

That would be the TFI system. The gray block on the dist, with the wires plugged into it, is the module. Takes a rather small, special tool to remove/install. If you have to replace the module, make sure to clean the mounting surface well, and use the white thermal paste that *should* be supplied with the replacement module.

 

Thanks for the help. Sounds like this is a faily likely culprit for the symptoms. Is this a replacement that can be done with the distributor in place?

 

Some can be replaced without pulling the distributor, others can't. It really depends on the situation and engine/options.
I've never tried it on a 302, so I don't know for sure.