You may have one or more of a few things going on there.
1. The infamous hot start problem due to fuel vapor lock problem on 70-74 914s - if your fuel pump is in the engine bay, then it gets so hot that vapor bubbles form in the lines whenever you stop & it gets no fuel. The best solution which Porsche did a service bulletin for, has the fuel pump relocated to up behind the steering rack below the fuel tank (in 75-76 models they move the fuel pump up front for that reason).
It's not a running problem in hot weather as long as you don't shut down, since the fuel running thru the pump cools it enough to prevent vapor forming (as soon as you shut down the hot fuel pump forms the vapor), so you could leave it running for a quick pee stop with someone else in the car.
A temporary fix is one of those heat blankets that some of the Porsche supply houses sell for it, but the fuel lines can still bubble up & cause the pump to cavitate.
So you really want a fuel pump relocation kit like AA & maybe others sell - or make up your own looking at the kit - then move the pump.
The "in the field" solution is to let it sit & go have a milkshake or something, until the fuel cools down enough for the bubble to turn back to liquid, & you could take water up under there to pour on the pump to cool it down, but I wouldn't on these rust prone cars - plus it's very tight & a very hot engine, tins, etc.
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2. The ole "flat spot" on the starter's rotor problem - the Bosch starters on all air cooled & some water cooled VW's & Porsches get hot & develop a bad contact area or "flat spot" on them & when you stop for food/lav breaks, then they can refuse to start/turn at all.
The solution is a new starter - OEM Bosch or upgrade to a hi-torque aftermarket one (several out there).
The old school "in the field" solution is to reach or get under there with a ball peen hammer or wrench or something & tap the starter casing hard-ish (NOT the solenoid)
while someone else in the car turns the key to start it. It may take 2-4+ tries, but that usually breaks it loose to get the starter to turn.
It only works if someone else is turning the key to start..
3. Related to the above, is the solenoid sticking due to the heat expanding the mechanism, so it cannot push the starter gear into the engine's ring? gear (spacing on the gear name now) to start it - as discussed by others above.
The fixes are the high torque starter, hot start relay kit &/or running a new set of direct wiring lines to the battery with a protective relay yourself - since the old wiring as it ages has more resistance & gets less "juice" to the starter (my mechanic recently did the latter on our `88 Westy waterboxer for tough hot starts on it). I've never heard of the Ford solenoid thing, but maybe that works too??
The old school "in the field" solution is to try the starter tapping above &/or a LIGHT tap with a screwdriver
on the solenoid if the other doesn't work.
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So I guess that's my contribution to the annual run of spring/summer hot start problem posts on here!
PS - Thanx Mark - I haven't come across that Ford relay / solenoid solution before!
Happy 4th & Thanx to those who served!
Tom
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