Not necessarily. A recess in the top of the tank can hold a top mount pump.Then a cover over that for access at skin. The pump sits below at bottom of tank, like in the car. It's workable.
>
> From: "Russell Duffy" <13brv3@bellsouth.net>
> Date: 2004/06/18 Fri AM 02:14:34 GMT
> To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
> Subject: [FlyRotary] Re: Fuel pumps in tank
>
> It is possible to mount the pumps in a RV tank using a stock fuel pump /
> holder assembly from a Ford EFI car.  Some Ford vehicles use an in-tank
> mount that is 'L' shaped; ie, it can fit in the outside/end rib and make the
> turn so the fuel pump is vertical.
>
>  
> Hi Ken,
>  
> I had figured something like this was possible, but there's no way you'll
> ever be able to replace one of those without removing the tank, and that's a
> pretty major hassle until you paint the plane, then it becomes something you
> want to avoid at all costs.  I don't see any way to do this without screwing
> up your paint.    Fortunately, if you buy a new pump, you'll probably never
> have to replace it.  Every decision is a compromise.
>  
> Cheers,
> Rusty (may actually get to fly this weekend)
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