" > Yes, it's possible for the rod to stop pumping.
> The rod is a tight fit in the bakelite "spacer" block.
> Once in a while, the bakelite swells with age and the
> rod gets real tight, Then, when the engine heats up,
> the rod sticks.....no pump.
>
> Vapor lock is a rarity in my experience, but possible.
>
> Oil should be hot. At freeway speed on a summer day
> it can get to 235F (not an absolute).
>
> Check that all the engine tin is in place and the foam
> seal doing its job. Check that the thermostat opens
> and the flaps open fully.
>
> You've checked the fuel flow; concentrate on the pump/rod.
>
> Jim

Also take Jim's earlier advise (i *think*) and check the carb bowl when you
have these problems...that will also help to confirm or eliminate the
sticking pump rod...the hot coil should be considered suspect IMHO....