Switching fuel pump from "in tank" to "in engine bay"

Question

Here are some mildly related questions about the pros and cons of moving a fuel pump from being in the tank to in the engine bay:

• In Tank Fuel Pumps Pros and Cons
• Is an "engine bay" fuel pump substantially louder than an "in tank" one?

Anyways, this question is about the process of switching over. I've read that "fuel pumps are better at pushing than pulling," so I suspect a special type of fuel pump it required. Other than that, I've found no major differences or hurdles to moving its location.

What am I missing? Surely, there's more gotchas to this than just:

• remove the in tank pump (adding some weight to keep the line sunk)

• buy a special pump that pulls instead of pushing

• cut the fuel line somewhere in the engine bay

• install the pump (paying special attention to noise dampening fasteners)

• this list is way too easy

Answer 1

The big thing you are missing is, in-line fuel pumps need to be gravity fed, which means they need to be below the level of the fuel. So, my suggestion to you is to put it along the bottom of the car where the fuel lines are running already. Just "splice" it in to where the line is and securely mount it. The good thing here is, I believe this still meets your criteria of being able to do a roadside fix, because you can put it somewhere you can still get to it. Maybe not as easily as you could in the engine compartment, but still, easy enough (much better than dropping the tank) to do it along the roadside.

There are MANY aftermarket options which will accomplish this for you. They mainly come from the performance industry, but they work just fine. If you go this route, most manufacturers suggest you put an inline fuel filter before the pump (pre-filter) and one inline fuel filter after the pump (post-filter). The pre- protects your pump. The post- protects your injectors and everything else.

As far as inside the tank when you pull the old pump, all you need to do is pull the pump itself, leaving the rest of the pump housing behind. Then get new fuel line (make sure it is ethanol safe everywhere - inside and out) and cut you a length which will go to the bottom of the fuel pump housing where the sock from the original pump would sit. Once you have it located, you'll need to secure it to the housing. I'd suggest using a jubilee (worm gear type) clamp and probably put some holes in the housing to run it through. This should keep it in place without putting foreign matter (weights) inside the tank.

Most fuel level senders are on the housing as well, so another reason why you'll want to leave the housing in place.

You'll also need to extend the wiring from the old fuel pump location to the new location. You'll probably want to get wiring of a higher thickness than original, just to be on the safe side and not cause any issues. You'll also need to be sure which wires you're taking, because usually the fuel level sender wiring is co-located with the pump wiring. Quite often they even share a ground, so be cognizant of these things or you'll need to start counting miles and hoping you're always getting the same fuel mileage.

Answer 2

Major ones? no! good reasons to do so NONE! It was not by accident that nearly all manufacturers have gone to in tank pumps. clearly, they are quieter, but let's add in some additional points of value. An internal pump that springs a leak does so while sealed inside a tank whereas in the engine bay the fuel sprays where it will and potential for a fire become huge. Yes the fuel lines are still on the engine however far less likely to fail due to high pressure design and federal regulations on leaks of all fluids. The pump is cooled while submerged where as a mechanical pump externally heats up while running.