I have a question I have an 84 F-250 the one in my sig. It has two fuel tanks, and an inline fuel pump (electric) on the frame just a head of the mid tank. Question is it that normal and is there a way I could go with an mechanical fuel pump I heard that there is electrical pumps in the tanks the truck has been "fixed" several times by the past owners so i do not knoe that the truck started out like. Any help would be great

 

Should be a low pressure pump in each tank, plus the high pressure pump on the frame rail. They may have 'fixed' em with a soldering iron or duck tape, who knows. I would fix them right and move on. A mechanical pump would not do you justice, and I'm quite positive not an option as far as the pressures and mechanics go. But yea, you have 3 pumps. Make sure you change the filters, and no cheap, nasty, dirty gas to tear up your new pumps. On second thought...do you hear the pumps running in the tanks? I'm not exactly sure of an '84 fuel set up. Instead of the 2 low press and 1 high press pump, they may have rewired the pumps, no longer pumping with the intank pumps, and just using an aftermarket inline pump on the rail.
There ya go..I did my best to confuse us both.

 

Sounds like you have the hot fuel option. There should only be the two in-tank pumps, with only the valve on the frame. The cheapest way to go would probably be to put a new electric pump on the frame, but the correct way would be to diag and fix the in-tank pumps and un-rig the rest of the system.

 

To answer peppy question I do not hear the pumps in the tanks but I do hear the pump on the frame rail. So I think from what you too have said I should make shure (1 that there is in-tank pumps and if so fix or replace them (2 replace the tank switching valve in the frame rail.... currently the front tank are hooked uponly the rear tanks are by-passed. Should I keep the third pump (booster pump) in place. I have the pressure releave valve in front of the carb (fuel return to the tank)