> doesn't the fuel pump use fuel itself as a coolant or something

I know very little about these things, but my understanding was always that any form of liquid pump uses the liquid itself as coolant to some extent.

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embedding-shape 16 hours ago | parent [-]

Yeah, fair enough, I think what he mentioned though, wasn't just about fuel going through the pump being used as coolant, but some extra process that only happens when you're not running below say 10% or whatever, an extra cooling process that only runs when you're not low on fuel. Maybe I misunderstood him though and it's just about the liquid passing through.

	▲	alias_neo 15 hours ago \| parent [-]
		I think the fuel passing through is the only method that could be used to cool, the volume of fuel required is presumably constant, regardless of how much fuel you have left, so the amount passing through the pump should be the same until you run out. On a related note, my car has a fuel heater, to pre-heat the Diesel before it hits the engine, I assume this is typical in modern cars, but using the fuel as a coolant would presumably contribute positively to this desire for warmer fuel entering the cylinders.