Fuel Tank Selector Valve?

Tiny
CMAB1
  • MEMBER
  • 1996 FORD F-150
  • 2WD
  • AUTOMATIC
I have dual tanks and we are having problems trying to find the fuel tank selector valve (if it even has one) so we can replace it and try to fix the problem.
Do you
have the same problem?
Yes
No
Wednesday, July 6th, 2011 AT 7:15 PM

38 Replies

Tiny
DOCFIXIT
  • EXPERT
Hello,

The fuel switching valve is on the side of the frame rail here are instructions and diagrams to show you how to change it out. Check out the diagrams (Below). Please let us know if you need anything else to get the problem fixed.
Was this
answer
helpful?
Yes
No
+1
Wednesday, July 6th, 2011 AT 7:24 PM
Tiny
HERCULES275863
  • MEMBER
  • 1996 FORD F-150
  • 5.0L
  • V8
  • 2WD
  • AUTOMATIC
  • 239,000 MILES
Fuel transfering from 1 tank 2 the other when driving just replaced both pump assemblies.
Was this
answer
helpful?
Yes
No
+2
Saturday, May 29th, 2021 AT 11:18 AM (Merged)
Tiny
ASEMASTER6371
  • EXPERT
Good afternoon,

The fuel switching valve by the rear tank is stuck open allowing fuel to transfer. It should allow fuel from one tank only to the front, not transferring. I attached the location of the valve and the description.

Roy
Was this
answer
helpful?
Yes
No
Saturday, May 29th, 2021 AT 11:18 AM (Merged)
Tiny
WINEMAN262
  • MEMBER
  • 1996 FORD F-150
  • 4.9L
  • 6 CYL
  • 2WD
  • MANUAL
  • 203,000 MILES
Have the truck listed above Eddie Bauer regular bed dual tank. I get fuel pumping from front tank to rear only. Runs fine on both tanks but seems the front pumps either it's return to the rear or pumps to the rear tank. Thought it might be the dual tank selector valve, but did not appear to be one along the chassis rail. Not sure if it is the fuel pump check valve problem in either tank or what. Ford says that it has a F1UZ9B263B fuel tank valve. But I can't seem to locate it anywhere. Can't find a schematic diagram of its location. Seems like both tanks T off main line to each tank. Assume same for the return line. Thanks for any help.
Was this
answer
helpful?
Yes
No
+1
Saturday, May 29th, 2021 AT 11:18 AM (Merged)
Tiny
JACOBANDNICKOLAS
  • EXPERT
Hi,

I think I know what is happening. There is a fuel tank reservoir valve under the vehicle that is the likely problem. If you look under the driver's side door on the inside of the frame, there should be a black canister/fuel reservoir. See pic 1.

Check for that first. If it is there, you have two choices. You can purchase them on Amazon or eBay or you can try fixing the one you have.

What you will need to do is remove it from the vehicle, and remove the (I think 8) 10mm bolts from the top of it. When removed, there will be an orange diaphragm with one screw holding it in place. Remove the screw to expose a steel round plate. See pic 2.

I circled the part I am referring to in the pic. That is the item that determines if the front or rear tank is being used. Now, that steel plate can move up and down. When down, the front tank is being used. When down, the rear is used. What happens is the two steel slide rods attached to the round plate get dirty and no longer freely move up and down. As a result, fuel goes to different tanks when it shouldn't.

Take a good penetrating fluid and spray along the slides that hold the round plate and work it up and down until if feels free and moving smoothly.

Next, put it back together. Because there is fuel pressure in the reservoir, make sure to use a good sealant designed for fuel and heat when you reseal the top.

Let me know if you find it and if this helps. I've done it before because of the cost of replacement parts and it has worked fine. However, I can't guarantee it will do the job in all cases.

Take care,
Joe
Was this
answer
helpful?
Yes
No
+1
Saturday, May 29th, 2021 AT 11:18 AM (Merged)
Tiny
KEN
  • ADMIN
Yours might not have a valve because it was a mid year shift. The reason the tank fills is because the check valve on the pump has gone bad. We used to replace both fuel pump assemblies when this happened which fixed the problem, but you may be able to locate the bad valve if you pull the front tank down. Here are the instructions in the diagrams below to help you fix the problem.

Fuel Pressure Check Valve Locations Components - COMPONENTS - Mounted on the In-Tank Fuel Pump.
Was this
answer
helpful?
Yes
No
+1
Saturday, May 29th, 2021 AT 11:18 AM (Merged)
Tiny
WINEMAN262
  • MEMBER
Thanks Ken. This is a big help. As you probably know Ford does not really support the older vehicles. These forums are about the only reliable source for information like this. Really appreciate this. This is what I assumed happened to this year. Thanks again
Was this
answer
helpful?
Yes
No
Saturday, May 29th, 2021 AT 11:18 AM (Merged)
Tiny
KEN
  • ADMIN
You are welcome please let us know what you find. Use 2CarPros anytime, we are here to help. Please tell a friend.
Was this
answer
helpful?
Yes
No
+1
Saturday, May 29th, 2021 AT 11:18 AM (Merged)
Tiny
DKIEFER774
  • MEMBER
  • 1996 FORD F-150
  • V8
  • 4WD
  • AUTOMATIC
  • 120,000 MILES
When I depress my rear tank switch my truck instantally dies. So I took it to a repair shop they replaced the rear fuel pump and the front /rear dashboard switch. And it still dont work? Ant suggestions. Thankyou
Was this
answer
helpful?
Yes
No
Saturday, May 29th, 2021 AT 11:18 AM (Merged)
Tiny
DAVE H
  • MEMBER
Hello .. thanks for the donation ..much appreciated

Use a voltmeter to check you are getting a hot feed to the pump .. did the shop replace the whole FDA unit or just the pump .. the sender unit handles the tank switching ?

Fuel Delivery Assembly (FDA)
The FDA consists of a fuel pump inside a reservoir that is attached to the pump and sender assembly. See Fig. 1 . In a 2-tank system, there is one FDA per tank. Fuel sender assembly handles the fuel switching through internal valves.
Fuel reservoir is used to prevent fuel flow interruptions during extreme vehicle maneuvers when fuel tank level is low. Reservoir is located in-tank and is either molded or welded into fuel tank or is part of FDA.
Shuttle valve opens fuel return line to fuel tank when fuel pressure on shuttle diaphragm exceeds opposing check valve spring force. When pump is de-energized, supply check valve closes to maintain pump prime and fuel supply line pressure.
A portion of high pressure flow from the pump is diverted to operate the venturi jet pump. The jet pump draws fuel from the tank into the FDA. This ensures adequate fuel supply during extreme vehicle maneuvers and steep vehicle attitudes when fuel level is low. If FDA is defective, it must be replaced as an assembly.


https://www.2carpros.com/forum/automotive_pictures/266999_150_7.jpg



hope this help's


https://www.2carpros.com/forum/automotive_pictures/266999_AAA2_654.png

Was this
answer
helpful?
Yes
No
+3
Saturday, May 29th, 2021 AT 11:18 AM (Merged)
Tiny
OLE GLORIOUS
  • MEMBER
  • 1996 FORD F-150
  • 4.9L
  • 6 CYL
  • 2WD
  • MANUAL
  • 2,238,863 MILES
Front pump works and rear does not. Front pump was replaced two years ago and ever since the return fuel feeds to the rear and not the front tank, is there a way to switch the return fuel feed back to the front?

To add to the description based on my diagnostic checks, I checked the fuel selector switch and fuses associated with the switch, checked the fuel pump fuse at the relay box. Checked for any obvious shorts in the power supply to the rear pump. Everything appears to be fine in those areas. I do not want to crime the return line to the rear tank so I was thinking maybe a way to disable the rear tanks power would tell the engines sensors to send it back to the front tank. Is this possible? If so then why would it send the return to a faulty fuel pump anyway?
Was this
answer
helpful?
Yes
No
Saturday, May 29th, 2021 AT 11:18 AM (Merged)
Tiny
STEVE W.
  • EXPERT
The return line is connected to both tanks. The only way to make sure it returns fuel only to the front tank would be to modify the return line so it only goes to the front tank. The system does not know the pump is bad as it does not monitor the pumps other than turning them on and watching the fuel pressure.
Was this
answer
helpful?
Yes
No
Saturday, May 29th, 2021 AT 11:18 AM (Merged)
Tiny
CARL1125
  • MEMBER
  • 1996 FORD F-150
  • 152,000 MILES
On my 1996 f150? It starts fine and run good then it has no acceleration, like its running out of gas
Was this
answer
helpful?
Yes
No
Saturday, May 29th, 2021 AT 11:20 AM (Merged)
Tiny
KHLOW2008
  • EXPERT
You would need to test the switch or check the fuel pump operations when you toggle the switch.

Poor acceleration should not be due to a bad switch. If it is due to lack of gas, it could be a clogged filter.

If the MIL is indicating, you need to get a scan done to retrieve the trouble codes and proceed from there.
Was this
answer
helpful?
Yes
No
-3
Saturday, May 29th, 2021 AT 11:20 AM (Merged)
Tiny
CARL1125
  • MEMBER
It was a bad fuel tank selector valve thank you for the help
Was this
answer
helpful?
Yes
No
+1
Saturday, May 29th, 2021 AT 11:20 AM (Merged)
Tiny
KEALEYS_DAD
  • MEMBER
  • 1995 FORD F-150
  • 6 CYL
  • 2WD
  • MANUAL
  • 150,000 MILES
My F150 is equipped with dual tanks. When I switch from the rear tank to the front tank it seems to 'starve' the engine of fuel for 1/2 a second or so.
Yesterday, when I switched from the rear tank to the front tank, there was simply no fuel being delivered to the engine. When I switched back, everything was fine. I think it could be a fuel pump issue from the front tank. But not sure. Hopefully you guys know what the deal is.
Was this
answer
helpful?
Yes
No
Saturday, May 29th, 2021 AT 11:20 AM (Merged)
Tiny
DAVE H
  • MEMBER
FUEL DELIVERY
System Types
Electric fuel delivery systems differ in design depending on model. System designs use one of the following configurations:
Single tank with a single fuel pump.
Single tank with one Fuel Delivery Assembly (FDA). See Fig. 2 .
Dual tank with one FDA per tank.

Fuel Delivery Assembly (FDA)
The FDA consists of a fuel pump inside a reservoir that is attached to the pump and sender assembly. See Fig. 2 . In a 2-tank system there is one FDA per tank. Fuel sender assembly handles the fuel switching through internal valves.
Fuel reservoir is used to prevent fuel flow interruptions during extreme vehicle maneuvers when fuel tank level is low. Reservoir is located in-tank and is either molded or welded into fuel tank or is part of FDA.
Shuttle valve opens fuel return line to fuel tank when fuel pressure on shuttle diaphragm exceeds opposing check valve spring force. When pump is de-energized, supply check valve closes to maintain pump prime and fuel supply line pressure.
A portion of high pressure flow from the pump is diverted to operate the venturi jet pump. The jet pump draws fuel from the tank into the FDA. This ensures adequate fuel supply during extreme vehicle maneuvers and steep vehicle attitudes when fuel level is low. If FDA is defective, it must be replaced as an assembly.


https://www.2carpros.com/forum/automotive_pictures/266999_pump_10.jpg

Was this
answer
helpful?
Yes
No
+5
Saturday, May 29th, 2021 AT 11:20 AM (Merged)
Tiny
CAPTAIN DAVE
  • MEMBER
  • 1994 FORD F-150
  • 5.0L
  • V8
  • 4WD
  • MANUAL
  • 129,000 MILES
Shut truck off while running on front tank. Five minutes later would not start. Started on rear tank, and would quit when switched back to front tank. Just put gas in both tanks, and read 1/2 each, will not run on front tank. This is my son's truck which he purchased a month ago, had been sitting quite a bit, though has been running fine since purchased. I do know history though don't know if old recalls were dealt with.
Was this
answer
helpful?
Yes
No
Saturday, May 29th, 2021 AT 11:20 AM (Merged)
Tiny
HMAC300
  • EXPERT
See pic on how to diagnose this system. It's apdf file.
Was this
answer
helpful?
Yes
No
-1
Saturday, May 29th, 2021 AT 11:20 AM (Merged)
Tiny
KEN
  • ADMIN
Hello, We had a truck in the shop the other day had the same problem, it ended up being the tank switching valve was bad, we replaced it and the problem was fixed. These valves are difficult to test or I would have you check it out.

Please let us know if this fixes your problem.

Best, Ken
Was this
answer
helpful?
Yes
No
-1
Saturday, May 29th, 2021 AT 11:20 AM (Merged)

Please login or register to post a reply.

Sponsored links