dandaman

New here, this has prob been covered before but does anyone know where to get a tank switch for 86 f150 dual tanks 302 EFI. Thanks Dan

klricks

Item 24 here: http://www.lmctruck.com/icatalog/fd/full.aspx?Page=41
Edit: On second look I am not sure if the above is the correct switch for the EFI?????

Or an automotive generic DPDT type switch could be used.

How do you know the switch is bad?

dandaman

well I don't know yet, waiting for Haynes manual to come from Amazon, got truck last week, original owner had passed away, but relatives thought that he told them fuel pumps were bad, but both of them, its a dual tank truck? since then been trying to figure it out, high pressure pump works but nothing out of either back tank. Do you have a clue?

Chris_1

iTrader: (1)

It could be both - they may not have both gone at the same time.
That's a pretty simple switch on the dash, you could certainly test it easy enough.
And some of those older switches can be taken apart and repaired if that turns out to be the issue.
A test light and a cheapie multimeter would be your friends on this one.

dandaman

well its not the switch, pulled back and front tanks, could never hear them running, some say you should hear them, even got my wife, which can hear near everything in the eastern Untied States, to listen, not hearing it. The previous owners wife, he has gone on to glory, said that the old guy thought that the fuel pumps had gone out. I can assume that one had gone out then the other finally gave up. When I pulled the back tank the rubber line between the pump and the steel nipple had turned to mush, probably because of ethanol fuel, well that and being 31 years old, so no fuel was passing into the lines only returning to the tank, yep, that would do it, but the pump ran, I was encouraged that noting electrical was wrong. Then I pulled the front tank and the hose was completely gone, eaten up and gone. That pump did not run and the tank was extremely rusty inside. I begin to look for someone in Raleigh, NC to clean that tank, found someone, wanted 300.00. Well you can buy one for 90.00. I was looking on line to see if someone had cleaned these tanks at home. I read about putting white vinegar (2gal) into the tank with some sheet rock screws and rolling and turning the tank so the screws would knock off the rust, I thought what do I have to lose? Well I cant even begin to tell you how well it worked. I pressure washed the inside of the tank as best I could to get all the rust out that would come out. I put the screws and the vinegar into the tanks and worked it back and forth turning and twisting the tank in hopes of running the screws over the inside of the tank and "scraping" off the rust. I left the vinegar in the tank about 4 days, turning the tank everyday as I remembered to do so. Today I got the screws all out, and again pressured washed the tank, its pretty amazing how well it worked. Just kept on with the pressure washer until I thought I had gotten all the rust out, then started with just the hose and high pressure nozzle until I got all the scale out. I put a box of baking soda into water and worked it around inside the tank to halt the action of the vinegar. I dried out the tank with a wet vac and blew it dry as best I could then made a heavy solution of 2 cycle oil and gasoline (about a gallon) and poured it into the tank, making sure I had covered all the walls inside the tank. Now waiting on the pump assy to reassemble everything and get blue Fred going again. I have read a lot about how to diagnose these pumps and associated switches, no one had ever said a word about, it might be the rubber hose inside the tank. Hope this helps someone, let me know.

klricks

I had same problem with the connector hose on my rear tank.
I mentioned that in my web site link in sig.......

Your next task is to see if the problematic switching valve is working. Ford calls it a Dual Function Reservoir (DFR). There is a replaceable fuel filter inside the earlier versions 85-86. In order for the DFR to function properly, both low pressure in-tank pumps must be operational. The valve is a non electric diaphragm type which is operated by fuel pressure from the selected in-tank pump. If not working then strange things happen such as fuel being returned to the wrong tank. Fuel mysteriously pumped from one tank to the other etc.
I replaced my DFR with an electric solenoid type switching valve.