I have an 1983 F-150 with a 300/6 motor with dual fuel tanks. It is running on the front tank and when I switch to the rear tank it shows as empty and still pulls from front tank. If anyone could help me with this issue it would be greatly appreciated.

 

It sounds like it could be a bad selector switch on your dash, use a multimeter to test it. If it tests good, check to see if you have +12v going to the rear fuel pump, if you do, try cleaning the connections and check it again. To me i would think it's the switch on the dash because if not, 2 things would have to of broke at once, either the fuel pump AND your sending unit went out at the same time, or your frame mount fuel resivore clogged up (went bad) AND your sending unit went bad at the same time. So start with that switch on the dash.

 

Thank you for the information. I had the the truck torn apart yesterday and really couldn't get to the back of the switch. Do you know an easier way to get the switch out by chance?

 

On my 89 you take the wiper and headlight ***** off and pull the entire part of the dash off.

 

An '83 doesn't have a reservoir or an electric fuel pump. It has a mechanical pump on the engine, and an electric selector valve in the frame. I don't have pics or diagrams of that fuel system because it's so old. So if you can upload pics of yours, it will help us help you, and others in the future. This thread explains how to upload them free & embed them in your posts here:
http://www.supermotors.net/forums/th...-and-or-videos

To get the '80-86 radio bezel off, remove 2 screws across the top of the bezel and then remove the bezel. It may help to open the ash tray. The HVAC control panel comes out the BACK, so removing it can be difficult. But since the bezel hides the dash shell, you can cut out some of the unneeded plastic to allow you to work the panel out the front. It still won't be easy because of the control cables & wiring.



But I don't think it's necessary to get inside the dash - I think you have a bad selector valve, and either a bad level sender or a sunk float.