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Starting and shutting down-basic engine questions

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Evan

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It's my understanding that the priming knob pumps fuel directly into cylinders.
Turning the propeller , if the throttle is open a bit, will pull air and fuel into the cylinders, probably in a more-or-less stoichiometric ratio necessary for combustion. So why prime ? Is it necessary ? Or just more expedient ?

What is the best way to shut down an engine that has a mixture control ? It seems like shutting down with mixture control would be advantageous as it starves engine of fuel. So if mag switch stays hot, turning prop should not bring engine to life--as long as you turn off mags after engine has stopped.

Will pulling mixture to idle cutoff prevent fuel from leaking onto floor if carb float valve doesn't close all the way ?
 

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