Better yet...
Instead of using either the Ford Factory set-up of two in-tank pumps and the reservoir selector ($$$), or the two separate three port valves described in the previous post, a person could use one 6 port Pollak valve number 42-159 in conjunction with a universal electric fuel pump installed after the transfer switch before the high pressure pump. I guy could even throw a fuel pressure regulator in there if he wanted. The in tank pumps would be replaced with a section of submersible in-tank fuel line. This hose is made by Gates, available at Jeg's. The remainder of the system could be standard metal tubing, appropriate fuel injector hose, and proper fuel injection clamps. The standard in-cab switch and fuel level sending units would be retained.

This way you eliminate the cost of the tank pumps and reservoir switch, have a single universal electric pump mounted below tank level feeding the high pressure pump, then off to the filter, injectors, pressure rail regulator, then back to the correct tank through the Pollak valve.

All parts are readily available without dealer intervention, the modification is relatively easy and, more important, sustainable.

 

So here is my problem and questions...
I have a 1986 f150 xlt efi dual tank..the front tank was removed by the previous owner. The truck ran well for a few weeks, then began sputter or hesitate slightly ever so often. Then the truck just stopped running while i was driving, as if were out of fuel. I checked the fuel filter and its gtg, the high pressure pump works. I assumed it was either the sending unit or the dual function reservoir. I took the reservoir apart and it seems to function fine. So i wonder if the switch on the dash could be faulty? If so, can i just cut and paste wires so it just gives direct power to the rear tank? Also, since i am only running with one tank can i just eliminate the reservoir all together?

any help would be grand!!

thanks

 

You should really diagnose the situation first by checking the fuel pressure at the fuel rail on the engine.
You didn't say what engine you have but the pressures are listed within this site somewhere.
The 4.9 pressure should be around 40 - 50 psi with a max of 60.
Once you know what the pressure is, you can determine if the problem is a low or high pressure pump, fuel restriction, or fuel regulator.


You shouldn't need to remove the fuel reservoir, it'll just sit there in line and do its thing.

If you do remove the reservior, hang onto it, they are expensive to replace!

I just replaced both tanks because the back tank was unused and rusty. I have a good front tank with filler neck that needs a sending unit and vent grommet, if you want to have both tanks functional again. Not sure about shipping to Canada though... <O</O

 

Hey Swineren.

I have same problem with my 87 F150. It is the mechanical 6-port valve, no electrical connection. I think it is hung up in between or dirty filter. I took main pump out and tested it with battery and wires, with a 5/16 fuel hose on inlet side hanging in a can of gas. It really threw out the gas and good volume. And I do have 12V at the main pump leads each time the key goes ON. I took both gas caps off and could hear each pump running when selected with key ON.

When I removed the quick fitting from the main pump there was only a very little fuel with several attempts after selecting either tank. When I removed the quick fitting from between the selector valve and main pump, likewise only a little gas. However on side where lines come from tanks, the first supply line I opened just poured gas continuously as if it would siphon the tank dry if left disconnected. (Power was disconnected at battery) Tells me gas is getting to the valve seemingly anyway.

Easier to clean/replace valve than to pull even just one tank for pump replacement. Seems like must be valve stuck midway in my case. Am planning to remove and tear down and clean. NAPA sells the paper filter replacement in the bottom. Mayabe O-rings too. Likely that could be plugged up since I get same results from whichever tank I select. So I figure to replace O rings and paper filter element. Never been apart on my truck to my knowledge so plugged filt and or sticky valve strong possibility. Can use some sawed off and de-burred 3/8" bolts to plug up the quick fittings for the two supply lines from the two tanks so they don't run fuel continuously. I can be reached via email if you need to ask more. gsim@tds.net

Gerry

 

Hey Wyliard,

I have problem with my 87 f 150, 302. I think it is my valve. In your case, I would just take some rubber fuel line hose and four hose barbs and cut and plumb the thing so as to completely bypass the selector valve. Do not forget the return line. If I fail in all other attempts, that is what I will do with mine. I do not travel cross country anyway so I do not need the dual tank feature.

You could have a faulty dash switch. To test, select the tank you want and remove the gas cap. Just go listen to hear if the pump is at least running when selected and ign sw ON to RUN position. Easy to hear it whirring in there. If quiet outside, I can hear mine without removing the cap.

Another test is to see how much gas is in the supply line leading INTO the selector valve from the tank you do use. I thing the inlets FROM the tanks are on the bottom and the return lines are on the top part of the valve body. Mine is a vertical mount mechanical only selector valve and that is the connection info for it. A lot of gas and maybe even not stop running when quick fitting removed indicates to me that the fuel is getting there and trouble is in valve body.

I can be reached directly at gsim@tds.net

Gerry

 

i have a 1989 E-150 V8 5.0 302 1/2ton van dual tanks with efi by the engine with 63300 miles. i have the rear tank selected and the fuel is getting to the motor, but it is also going into the front tank and is being pressurised. i think i am the only person in the world letting gas out of his tank in this bad economy. I have rust in both tanks, and i am planning on getting news ones soon. I think the rust has really messed something up. I have just replaced the in cab tank selector switch and hard wired it in because the new switch they had for it at Auto Zone wasn't a harness package. At Auto Zone they told me that there is a 3 port motorized control valve, and it is to be found. All i see under the van is what know now from reading the posts on here is the "dual function reservoir" with 6 ports. I don't have the money to spend on parts i don't need. i can hear both of my pumps working in the tanks so i haven't checked the electrical connections. I am assuming that they are ok. I took off the bottom two lines and the two lines on the other side and turn on the pumps and when the ef pump kick on it was shot fuel back towards the filter and tanks, and i don't think that was the return line it was coming out of. i am mind boggled and seriously need help

 

calvery24,
You have a bad dual function reservoir and you can only get them from a Ford dealer.

 

Subford is correct. I have same problem and cannot find it anywhere except Ford dealer. It is $232 or so here in E Tenn. Am getting mine tomorrow. Have not had $100 repairs on my old F 150 in 13 years, so I do not feel too bad after all.

If you feel adventurous, you can order an electric generic 6-port fuel tank selector valve from say, J C Whitney for around $83 or so. Have to change all 6 lines over to rubber hoses and run wire to it and install a switch in the cab. I just opted to bite the bullet and buy a replacement. Will try to repair mine this eve, but pretty sure is it hopeless. Not made to repair.

Gerry

 

Calvery 24,

Forgot to say that you can tell a lot by taking the fuel tank supply lines loose at the selector valve. If like mine, they are quick connects so they are easy to slip off. May have to pry with screwdriver gently to start the thing moving back away from the selector body after the keeper is pulled out. Be careful here and be sure to have battery disconnected before starting this. You should see a lot of gas and it should likely pour out non-stop on both supply side lines from both tanks even tho power is disconnected. Pressure on a properly working tank pump is only around 5 PSI. Like you, I heard mine working in each tank when selected and ign sw in RUN position.

The supply lines on mine looking towards the two tanks were those closest to drive shaft. The return lines on tank side were those closest to outside of truck, or closest to frame rail. The supply lines from tank are 3/8" dia and the return lines are 5/16 dia. I took two bolts and sawed off the threads and made stoppers for the two supply lines from the two tanks to stop the gas from running out. Worked like a charm. Return lines only dripped a bit when taken loose.

gerry

 

Calvery 24,

I forgot to mention that I found out that there is no filter element in the bottom of the reservoir. It is just for the gas to collect in for the main pump to draw from. NAPA lists a paper filter element for the reservoir in some of the fuel selector valves, but it is not for my '87 ford 302 for sure according to Ford Dealer parts dept.

 

Well here is another question for you guys. Now like I said i have a big rust issue. what i was thinking is that maybe just maybe it could have gotten clogged with rust, like the 6 fuel filters this month have. When i emptied the filters they had chunks of rst come out. So with that in mind could i possibly take PB Blaster and Carb Choke cleaner to it. To tell you the truth i really don't have that kinda money to spend. This past month I bought the van, changed the oil, sparks plugs, fuel filter 6 times cause it sat for two years(needs new fuel tanks), replaced exhaust manifold on passenger side(need to replace the drivers), installed a cd player, wiper blades and driver wiper arm, side view mirrors, rear view mirror, got a spare tire cover(need five new tires), fuel selector switch. Now you guys if you think it is possible to save a little bit that would be nice, but if i can't then i guess i will have to bight the bullet and buy it. Can i get one from a junk yard? There is a van at the pull a part here that is exact to mine. Is it a possibility cause for two bucks i can get a thirty day warranty.

 

Calvery 24,

Can you see any rust on the current tank? In your place tho, I would definitely get another tank at a salvage yard. I would not hesitate to have it cleaned at a radiator shop either. The longer they sit with old gas in them, the worse they become. Any vehicle that has fuel injection is far more sensitive to the crud layer in an old gas tank than a car with a carburetor is. I saw that first hand with a Toyota that I had that eventually got to where it would no longer run due to needing injectors replaced. You have had water in your old tank at some point to have all of that rust present, clogging filters, etc.

You might want to change the strainer on the pickup/sump of the in-tank pump. That item should be brand new. That has to be defective to allow so much rust as to cause you to change external filter 6 times. You might even want to have the in-tank pump included in your purchase of that salvage tank. Likely it has not pumped nearly as much rust/crud as your current pump? Worth considering.

Gerry

 

You can try cleaning the selector valve but I had to have my wife take the push keeps out that holds the two valve down. I am not good at that and I would tear them up. But if you can get the "O" rings to slide and seal on the two valves you should be able to clean it.

I do not know where you can get any parts for it so you would be on your own there but I will post a link below and some photos of one that I took apart.

Note that the link to a replacement valve in this link is no longer working:
Ford E

Some photos I took and a diagram I drew.

These photo I hijacked:

Note only the 1985 and 1986 have filters in them:


These I took or drew:














/

 

Great post, subford. Identical selector to mine except I think my reservoir is a bit deeper. If I can get diaphragm and plate mount detached from the two valves like your wife did, I will try to remove and clean both of mine as well. I do have concern that I could not get them reattached as tight as they are now tho. Still worth trying as the stealership here wants around $235 before taxes here for a new one.

Gerry

 

SubFord, that was one of the best posts I have seen to date....consider yourself commended!