the tanks on my 87 f150 are screwed up. with both tanks full, switch selector on rear, gas overflows from the front tank. if i leave it on front, it seems fine. bought a new tank selector valve, but cant find it on the truck. now after reading about this problem on this list, i wonder if that is the problem after all. i have changed the electric fuel pump on the frame rail, also the filter, now i hear there are pumps in the tank as well. what next o gurus of fordom?????

 

I believe your truck came without in-tank fuel pumps. It has a pump somewhere along the frame rail and either a 3 or 6-way selector valve. In 89 or 90, they went to high pressure in-tank pumps that had built-in check or selector valves. Apparently fuel tank cross flow and overfilling is a problem in both set ups. But yours maybe an easier fix than later models...you may not have to pull the tank(s) or lift the bed to service the problem. I haven't read about how to check or change the 3 or 6-way selector valve on earlier models, but know this process is described in both the Chiltons/Haynes manuals. And you can check at the Alldata website (www.alldata.com) to see if there was a recall or TSB on this for your truck. Don't count on the dealer to honor the recall, however...my experience was negative so I filed a complaint with NHTSA on the web. Hope this helps

 

Hello,

I'm not sure about the 87, but my 92 had a recall for such a problem. Call the Ford Corp. and they will tell you if your truck has a recall.
I called them about any and all recalls, they told me what recalls had been made and said my truck had been fixed on every account already. Good luck.

Brian

 

I have been told to always use fuel from my front tank (89 F-150, 5.0) first, then go to the back tank. Reason? Return line from fuel injection only goes to front tank. So, if you have full front tank and use from rear tank first, it will overflow the front. One good thing about this is use from front first, then switch to rear and excess returned to front will give you a little more fuel in case you are in a pinch for finding gas station. This was told to me by a friend that has been a Ford service manager for 25 years.