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What I don’t understand…

So the designer's intent is to have the fuel pump operating any time the engine is running, and the objection of some owners is that having the pump going while doing ground maintenance is annoying. To me that suggests a solution where in the pump is powered not through the master switch but through the ignition switches (double-pole). Then you could update your databases in peace but still have the pump running any time you were actually intending to fly.

I don't think it's quite that simple... Van's wants the electric pump running for quite some time, I think a few minutes, before a hot start, to run cooler fuel to all the fuel lines fresh from the fuel tank and any warm or hot fuel back through the return lines into the fuel tank. There really isn't any recirculation for fuel once in the main lines from the 4 way on top of the engine going directly into the carburetors, but those carburetors fuel bowls are mounted a bit lower, so any vapor lock within would, by the force of gravity and fuel heavier than vapor lock, head for the highest point in the fuel system, the 4 way valve, where it would vent off back to the fuel tank return line.

Someone please correct me if this thought process is not right.
 
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