Ok...good morning. this issue has been posted on here in the general tech forum and Hanky has assisted me in attempting to locate the problem with my van stalling out while driving without warning.
This van would start and run. however since september of 2010 it has been randomly cutting out while driving and could be restarted anywhere from 30 seconds to a couple minutes. This situation went from dying out a couple times a week to everyday to where it now won't start. It cranks, but no start. Had removed the mechanical selector valve and took it apart and noticed that the valve stem springs (two of them) would not retract properly (slowly retracting). Ford wants around $292 for a new one and aftermarket shops sell them for roughly 50 bucks but you need to purchase additional fuel hoses, a toggle switch and a wire harness since the aftermarket selector valves are electric. Well, I neither had the money for the expensive ford part nor the patience to deal with an aftermarket piece that requires you to jump through hoops to get it attached and working right. So I disconnected the rear tank's electrical connector (cut the wire harness) and taped that up and removed the return and fuel lines from that tank from the selector valve; folded them over and placed clamps on them so they wouldn't leak gas (bad gas in rear tank, pump inside not working properly). I then took the front tank's hoses attached to the mechanical selector valve and with a suitable extension attached those hoses to the external pump and the return line as they are to be hooked up. I removed the selector valve. KOEO and went under vehicle to check for leaks....no leaks. Tried to start and no start. pushed the schrader valve in and no gas. checked the fuel regulator and no leaking.
I know that you can prime a fuel pump from the OBD1 tester but is that to prime the external pump? How can I check the in-tank pump that I am using? I'm assuming that I could just disconnect the fuel line from the external pump and then KOEO and see if the in-tank pump will pump gas out that hose....can that be done? I have no assistant to listen to the in-tank pump. My next question is regarding the four wires attached to the rear fuel pump...what are they all? one is red (which I assume is hot), two are plain black and the last is black with a white strip. I ask this because I had cut the wire harness going to that tank and removed that section that plugged into the rear tank pump assembly. I guess perhaps one of those wires deal with the inertia switch...but that's a guess......any thoughts? Thank You and Happy Easter

 

another question comes to mind....the selector valve contains a fuel reservoir. I removed the selector valve altogether. would the lack of a fuel reservoir cause the van to not get gas up to the fuel rail? If so, can I delete what's inside the selector valve, plug the ports for the rear tank, and just run the front tank hoses through it like that? I know the low pump pumps gas up into the selector valve and thus opens the valve and I guess the hi-pump pulls it up to the fuel rail. curious as to whether i ran the front tank right as described above

 

And here I thought you finished this job.
It's not a good idea to eliminate the selector valve assy ,....because it contains a return line to the tank. The mechanical selector valve is controlled from the low pressure pump. Only one set of pressure and return lines is active at a time.
If you are going to eliminate it you need to make sure the return line from the front of the vehicle can return to the tank in use.
I will send a diagram of the wiring for the pumps to you.

 

http://www.imgplace.com/viewimg825/5...tankwiring.jpg

 

Good morning. And thank you for the diagram, Hanky. No, unfortunately I haven't won the fight with my E150. I have the return line from the engine area attached to the return line of the front tank and the sending line attached to the external fuel pump. I cut the electrical harness from the rear tank and taped the existing wires up and under the vehicle, bent both hoses coming from that rear tank so gas wouldn't come out, removed the selector valve and after KOEO still no gas to fuel rail (schrader valve pushed nothing out). So, I now need to check that in-tank low-pump to make sure it's operating. But the problem was definitely within the mechanical selector valve (couple pics included of similarity) Those springs on the valve stems were bad....I pushed on them and they slowly retracted. new valve stem springs retract quickly. So that was the problem of the van stalling out while driving....apparently the valves either failed to open or close all the way resulting in some form of pressure building up inside that valve that when the van was turned off gas would leak from the schrader valve. To me that's a lot of pressure to blow gas out of that schrader valve. So it's time to check the wiring on the existing in-tank pump and then the pump itself.

 

If you can , can you tell me how to post pictures to this site . I don't really know and it would really be helpful then I probably could send more info to you or to who it would benefit. Thanks
Those 3 pix you posted are very informative and I never saw the fuel flow as clear as your pictures show.

 

good morning. what i did with those pictures was post a new thread...went down the screen a little bit until I found the image posting area (additional options)....clicked on that "manage attachment" area a new window opens and click on choose file. Find the file/image from your pc...click it...hit ok....then you come back to the window that opened and clicked upload. it uploads then close the window. hope that helps.

now, let me review that wiring diagram you sent me so I can find the problem. I think what I did was when I cut the harness going to the rear fuel tank apparently one of those wires was ground and so now I have an open circuit. so ill review your wiring diagram and find out which of the four wires from that tank need to be grounded.

 

believe me, I have spent hours searching for pictures of the 302 and several specific areas and have about 50-60 photos on my pc dealing with anything from air pump hose routing to the mechanical selector valve. I started doing that because of a hose that was not connected and I needed to find out where it went. No one around me has a 90 e150 to look at so the internet and I became real close friends for hours while I searched.

 

ok....my rear tank's wire harness consist of four wires: red, black, black, and black with white stripe. I disconnected the connector from the rear tank and tried to pull it out from the top of the tank towards the back o fthe van and the connector got caught between the top of hte tank and teh body of the van. so I just cut the harness and pulled the connector from the front of the rear tank over the rear axle. I taped up the wires exposed, tossed the harness in the van, tried to start but no fuel to rail. the wiring diagram you sent and the one I included has me confused. my diagram shows different color wiring for the rear tank (albeit it's a daigram of a 88 e150 but I am sure ford didn't change wiring color within two years of producing my van). your diagram shows two wires going to the selector switch and two wires traveling to the front tank wiring (I assume those two are grounds?). I think by cutting that harness off I created an open circuit somehow...yiou think?

 

correction: the wire harness wires from my rear tank are orange, brown with white stripe, and two black wires. im color blind so i thought they looked as i described above. if i cut that harness off the rear tank is that or would that affect the operation of the front tank?