I bought my 88 Ford Pick Up with duel tanks and wanted to check out the fuel mileage and filled both tanks and wanted to see what I got out of the front tank. Well, the gas gauges work for both tanks and I can hear the pumps running when I swicth over to either tank.
Now the problem, I ran out of gas today with the front tank and went to switch to the rear tank and it primed up to the switch over valve and that was it, the truck would not change over to the rear tank causing me to have to call the wife. (you can imagine how that went).
Is it possible to just put in valve I can switch by hand? Is this a bad idea or should I just try to find a new change over valve?
I dont take many long trips but it would be nice to retain both tanks for when I do take a trip. Any thoughts would be great.

 

More specs would be helpful. Engine size. Gas/Diesel. Carb or injected. If you know that you have pressure from the rear tank up to the selector valve and nothing from there up to the manifold then why not just change out the part instead of trying to rig something?

 

sorry about the lack of info on the truck, it is a injected 351 W. I think the reason for trying the odd ball repair is mostly money. I am thinking that the selector valve is costly compared to the T valve I will use. Any idea of the price of one. I imagine it is costly and it was something I was going to have to redo tonight. I now have a ride to work and may be able to get the correct part for it. The truck is a 88. Thanks for posting and pointing out my lack of info.

 

Buy the proper replacement valve. There is more to the valve function than just a T valve.

 

I think that is the route I will have to go, it did not even occur to my about the return lines and thinks like that .

 

There are three pumps on that truck. I would unplug the high pressure fuel pump located on the frame rail under the truck, and listen again to the in-tank pumps. If the in-tank pump is not working, the selector valve will not change over, since it is mechanically operated. The one pump might not be working, but you still hear the high pressure pump running making things sound ok.

 

All great replies, the last one got me more knowledge flowing, I have been driving Jeeps for the last few years and I guess I will have to go buy a book on the Truck to get a good feel for it.
The worst part is that the gauge works in both tanks but evidently not correctly in the front, but the rear works fine. It wont just change over and when I hit the button to change over tanks well the truck kept running and the gauges would switch over to the new other tank and the truck kept running, I even switched tanks on the way home to the non working rear and and it kept running on the front tank with the readin of the rear tank. So I thought everything was fine.

 

I removed the selector valve from the frame and traced which line goes to what tank and after reading about the valve in the repair manual I unscrewed the bottom of the valve and really did nothing more than clean it and reinstalled with a new O-Ring and then checked the operation of the in-tank pumps and watched each one flow and stop with the changing of the switch on the dash.
On a side note, I did notice that after hooking up the lines and then hitting the key again, the front frame mounted pump got its pressure and it quit working and I tried to start it and it then proceded to pump the air that was into the line in the tank, that is what it sounded like anyways.
Now I am running off of either tank and really did not do anything other than take the valve apart to inspect and the book stated there was a filter inside the valve on the older versions, there was no filter in my truck but it did appear at one time or another that their was.
A new non-servicable selector valve from the dealer list in the $90.00, but I was told I could have it for $76.00 warehouse cost. That is why I bought the O-Ring. I just got lucky for now anyways and the system works, I just hope the rear tanks gauge is more accurate than the front tank is.
Thanks to all who offered advise to me on this problem.