fuel tank valve issue

[NJGearhead666]

ok so i put my new rear fuel tank in and today i finally filled up the rear tank. so i leave the gas station with the truck running on the front tank i get on the highway and switch to the rear tank. the gauge reads good so im driving for less then a minute and the fuel light comes on. I switch back to the forward and the light went off. so i get home put the truck back on the rear tank let it idle for a few and the filter light came back on then a few seconds later the truck died. i put it on the front tank and cranked the crap out of it and it started.

its apparent that the truck is running out of fuel when on the rear tank. i have a general idea that its possible the fuel select valve frozen. the truck has been sitting for 2 years before i got it but how do i check the valve to see if its working?

im just glad i switched off the rear tank on the highway. i doubt it would have been fun having the engine die on the NJ turnpike at 70mph

 

[MUDKICKR]

sounds like the valve is bad, but disconnect the lines on the valve that go to the rear tank. run reg. rubber hose from those nipples on the valve to a fuel can. (if you can get clear it will work better) start the trk and have someone watch fuel can(or clear lines). switch to rear tank and see if it pulls fuel from fuel can. if it doesnt then the valve is bad. if it does pull fuel from the fuel can then you have a fuel line problen on the trk.

 

[MIDNIGHT RIDER]

One too many of these episodes is why you will find two manual valves beside the driver-door in my truck; over twenty years and they haven't failed me yet.


I have quite a collection of the factory six-ways hanging on the wall to remind me just how reliable the manual ones are.

 

[NJGearhead666]

yea im going to check it this weekend thanks guys

 

[hesutton]

One too many of these episodes is why you will find two manual valves beside the driver-door in my truck; over twenty years and they haven't failed me yet.


I have quite a collection of the factory six-ways hanging on the wall to remind me just how reliable the manual ones are.

Got some photo's of what was done or may be a diagram? Those valves are not my favorite part of my rig either. You should do a tech article as well.

Heath

 

[MIDNIGHT RIDER]

Got some photo's of what was done or may be a diagram? Those valves are not my favorite part of my rig either. You should do a tech article as well.

Heath

Alas, I ain't yet figured out the picture process, nor diagrams.

It was really pretty straight-forward.

When I have more time, I will try and explain just what I did.

 

[icanfixall]

I'll bet you probably pinched the fuel line suction to the rear tank when you installed it.....

 

[NJGearhead666]

I'll bet you probably pinched the fuel line suction to the rear tank when you installed it.....

I dont get it? you mean the hard lines that come out of the top? or the pickup part in the tank?

 

[icanfixall]

The hard line is actually plastic tubing. It can be crushed. By not being there when you installed it I can't say much more. But as posted above you may have a switching valve problem too. The valve has a motor that does the actuall switching from front tank to rear tank. The tiny motor drives open or closed the differant tank lines. Best to remove it and test it on a bench where you can listen and see it work or not. Be able to plug all the open lines and tag all of them.

 

[MIDNIGHT RIDER]

I will try and explain just what I did.

Although "stacked" manual fuel-valves can be had that have provisions for switching both DRAW and RETURN on a single valve, they are rather expensive; and, due to the extra effort required to turn two gates on one shaft, they will occassionally snap a shaft.


I much prefer using two seperate valves, one for DRAW and one for RETURN.

Besides being more dependable, there are some assets to being able to switch the RETURN independent to the DRAW; for instance, one tank can be emptied into another to facilitate a repair.


My fuel system consists of the two factory tanks and a big auxilliary tank for a total of three tanks.

Besides the normal plumbing requisite for a stock two tank system, I have an electric-pump in a by-pass line, a magnetic algae-killer, a GoldenRod pre-filter, a LUCAS glass-bottom sediment-bowl/water-seperator, two small inline filters, the stock filter, a piston lift-pump instead of the diaphragm one, a RETURN-line by-pass, a valved quik-couple hose for pumping fuel from my truck to another truck, tractor, or whatever, etc., etc.


I won't describe all the particulars of my manual valve installation, but will describe how it can be done on a more normal truck.

The valves I prefer are made by Weatherhead.

It takes two, one for DRAW and the other for RETURN.

In the area of the floor, between the driver-seat and door, locate and drill two holes through the floor for the operating stems of the two valves to protude into the cab; be sure to leave plenty of space between to clear the fuel lines.

Plumb the RETURN lines to one valve, the DRAW lines to the other, making sure to orient the lines the same on both valves.

I like to plumb such that the handle/indicator points forward for FRONT tank and rearward for REAR tank.

What I did for a long time was to cut the rigid plastic lines and simply slide rubber fuel-hose over the plastic lines and double-clamp; I ran this way for years with never a leak.

The spliced-on rubber hose gets connected to the valves.



The factory electric fuel selector also switches the fuel-gauge senders from FRONT to REAR; when it is eliminated another solution is required.

The gauge wires get connected to a DPDT toggle-switch.

Connect the wires that go to the gauge to the center terminals of the switch.

Connect the wires from FRONT and REAR to opposite ends of the switch.

I also mounted this switch through the floor, oriented such that when the toggle points forward it reads FRONT tank, and when the toggle points rearward it reads REAR tank.


I hope this makes sense.;p

 

[NJGearhead666]

The hard line is actually plastic tubing. It can be crushed. By not being there when you installed it I can't say much more. But as posted above you may have a switching valve problem too. The valve has a motor that does the actuall switching from front tank to rear tank. The tiny motor drives open or closed the differant tank lines. Best to remove it and test it on a bench where you can listen and see it work or not. Be able to plug all the open lines and tag all of them.

well i think i get what your talking about. but when i took out the old tank the factory braided lines that came off the hard line that runs along the frame to the two steel lines on the top of the sending unit pretty much fell apart when i touched it. I just replaced it with goodyear rubber fuel line.

 

[hesutton]

Thanks MNR. I'm going to keep this thread as a favorite for reference in the future. I know what I'm going to do when my Ford vavle dies.......AGAIN.

Heath

 

[Andylad13]

MIDNIGHT, thats real cool what you did, and i like how you can have your choice in which tank you want your return in. it makes perfect sense and im definatly interested in doing this mod.

 

[NJGearhead666]

UPDATE!

UPDATE! I disconnected the lines from the sending unit on the rear tank and used rubber hose to make them longer and put them into an clear empty 1 quart paint mixing cup up filled with diesel. started the truck on the front tank then switched it to the rear tank. the truck kept running on the fuel in the cup. i let it run like this for 10 minutes. and watched as fuel got sucked up into the feed line. and fuel would come out of the return line. so i figure the fatory 6 way valve is working fine. so i hook them back up to the sending unit start the truck on the rear tank and a less then a minute later the truck dies! I dont get it! i took the line back off and blew air into both lines on the sending unit and i heard the fuel bubble in the tank.

I just got home from working on it. any other suggestions will help im about to freak out so im going to have a beer and relax for a few. maybe it will come to me then.

 

[h2odrx]

How much fuel is in the tank??