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Fuel Pumps

Anybody know why they always mount the high pressure electric fuel pump inside the tank?? Millions of consumer dollars could be saved if the pump was mounted outside the tank. My guess is that it’s the cheapest way at the manufacturing level to do it and they don’t care about future repair costs…Or is there some other reason? I thought about safety…If the pump leaks a little, who cares? No one will ever know…

I always thought it was mounted in the tank to use the gas to cool the motor. Maybe it’s in there to reduce noise too. Just guessing here…

AFAIK there are two reasons to use in-tank pumps:

  1. It places the whole system under positive pressure, which reduces the chance of having something other then liquid gasoline in the lines.
  2. It puts the pump in an enviroment where it is very unlikely to cause a fire if it fails.

Early F.I cars (like CIS) cars had the ump outside,they were expensive and noisy,I mean like 300.00+ expensive.

My fuel pump is on the side of my engine block :slight_smile: But they’re in the tank for the reasons above but also, electric fuel pumps work better as “pushers” than “pullers”. Unlike mechanical fuel pumps.