Okay, now I'm a little confused on this.... I also have a 1990 with dual tanks (although mine's a F150), and am having the same flow problem as Knelsonconst (my truck runs fine from either tank though).

Does the fuel flow from the front tank to the rear via the supply lines, OR, does it get into the rear tank via the return lines??

Are we talking about an external check valve that needs replacing, or is there a weakness/failure in the rear in-tank pump allowing returned fuel to enter that tank instead of the front where it should be returned to (when running from thew front tank)??

Or am I more confused than I thought?

Wade

 

I'm confused as well... but that's not hard to understand.

I have the same problem mentioned, but it is only a problem in one
direction. Maybe if I give the exact details, someone can list for me
the exact part.

When I run off the front tank ('91 F-150) things function properly.

When I run off the rear tank, fuel is slowly moved from the rear to
the front tank. Also, it is hard to start the truck when the rear tank
is selected. Once running, it's fine, but it is hard to start.

Of course, a workaround is that I can fill both tanks, run the front
until nearly empty, then run the rear until the front is full again,
then continue running off the front. But if there is a fix that is not
too expensive I might want to try it.

Regards, Cliff

 

Guys, Mike just said it's a check valve in the fuel pump/sender assembly.

I wouldn't say the pumps are bad.............the're pumping into the wrong tank aren't they? lol

If you want the exact part number..........take this.....Ford's Recall #93S68 to the dealer and have them look it up or install it for you.


Mike.....hang in there fella. Your help IS appreciated!

 

https://www.ford-trucks.com/forums/s...l+check+valve+

[QUOTE from mikal1] for 1990 on onlyThe recall was for a defective check valve which allowed fuel to be pumped from the rear tank to the front tank. Which sometimes caused the front tank to overfill and spew allover when the cap was removed. Ford replaced a check valve and the fuel pressure regulator.




__________________
Quote from Jimmy- FTE Moderator Support FTE....Online Store

 

Thats ok! i thinks its confussing because a bad check valve in the fuel pump/sender assembly can do different things for people. I'm glad i never had fuel pour out of the cap. One person on FTE said he got it in the face when he went to fill his tank. This doesn't happen to everyone when this part goes bad. it's a good chance that all the reasons listed above are to do with this part being bad. It's a good place to start.

 

Thanks... a few years ago I went to the dealer and asked about it.
I was "within the month" of the expiration date for the recall on my
'91... and they acted like they didn't want to help. I got mad and vowed
never to go back. But if it's a valve on the outside of the tank I could
probably handle that.

 

Cliffrwarren, sorry to hear that! Did you register your truck with Ford Headquarters? They sent recalls out in 1994. Anyway I think you have 15 years and 150,000 to get it done. I believe the fuel problem must be present at time of repair to be covered by warranty. Call Ford Headquarters, I always ask for the manager, it saves time. Then call another Ford Dealer service department and ask for the Service Manger, Give him your vin number to see if there's a recall for your truck and if its still covered ( 15 years or 150,000???????) If the recall time is over call ford Headquarters ( manager) and ask if they will make an exception for your truck, tell what happened last time you went to Ford. Good Luck

Found your recall info at All data
http://www.alldata.com/TSB/20/91201701.html

Google internet search I found for 1991, F150 and 250 2 WDand 4 WD, 302 recall info for your truck:

"I have an F250 4x4 bought new in '91. In Oct '94 I received warranty recall
notice 93S68 which required dealer to remove rear fuel tank and install P/N
F4PZ*9155*B Kit#2 (fuel pressure regulator/check valve). This is to ensure
that excess fuel from injection system is returned to the same tank and not
the other one. If excess fuel is sent to other tank and that one is full,
overflow will result. At that time the dealer told me they had several
users complain of gas smell.
The above referenced recall and part number may only apply to trucks made
in Canada but it is worth checking into."


Recall info. for 1990 to 1993, may have a different recall number for later models 1994 to 1996

FUEL LEAKAGE IN THE PRESENCE OF AN IGNITION SOURCE COULD RESULT IN A VEHICLE FIRE.
DEALERS WILL HAVE A STAINLESS STEEL FUEL PRESSURE REGULATOR INSTALLED. OWNER NOTIFICATION BEGAN JULY 9, 2001. OWNERS WHO TAKE THEIR VEHICLES TO AN AUTHORIZED DEALER ON AN AGREED UPON SERVICE DATE AND DO NOT RECEIVE THE FREE REMEDY WITHIN A REASONABLE TIME SHOULD CONTACT FORD AT 1-866-436-7332. (FORD RECALL 93S68).

 

Thanks, well, I bought the truck used, immediately began looking into
the issue. It was right then that I took it in, but they said 12 years and
I was BARELY out of the recall at that time.

Seems to me, something potentially dangerous as this, they should go out
and search the hills for trucks that didn't have the fix and take care of
all of them................

 

Thats one reason I call companies and register everything i buy used or new, trucks, cars, kids toys etc. You would think when a person goes in for a repair at Ford they would check for recalls.

 

Ford did a recall 2-3 years ago. The dealer replaced the valve in my 93. I had the same problem and it fixed it. No cost to me. The bad part is the constant service reminders from the dealer.

 

IT TOOK ME 2 HOURS TO MAKE A 30 MIN RIDE HOME. Thats it, I got home ripped out rear tank plug the lines and now truck runs fine w/ just 1 tank. Yes ive been told to seek anger management help !!! Good news is I found a 1992 F350 4x4 crewcab w/ 60,000 miles on 460 motor but only goes in reverse, Will my transmission in my 1990 F250 4x4 w/ 351w bolt up to it. Help before I go beat the dog! (jus kiddin)

 

Originally Posted by onetonfan
I have a '91 with two tanks and I had the factory recall done. What the dealer did was install a check valve in one line at the rear tank. The check valve is about the size of my little finger. The gas line was cut and the check valve added in-line (hanging in the air). The front tank did not get one as the problem was stated as being only with the rear tank. Not a very complicated fix IMHO. Taken from FTE at


https://www.ford-trucks.com/forums/showthread.php?p=1934409#post1934409

Maybe you can connect onetonfan for more info. to see if he had the same problem, maybe its something you can add yourself. ?? Its cheaper then replacing the fuel pump, with brocken shuttle valve inside.

 

I went to the parts department and asked for all items to update my 90 f150 5.8. I was not given any "in line check valves" and after I replaced my FDM's(in both tanks) my front tank a month later started filling from the rear tank. I understand that the shuttle valve on the plastic FDM is either stuck open or weak, or the other tank is stuck shut or tight. I have blocked off my return line to the front tank and only run on the rear untill someone can tell me what really needs to be done. Is there anyone with a '90+ year model that has solved/overcome this. It seams everyone with answers is talking about the frame rail hi-pressure pump external selector models that I understand to have not been used after 1989. Is there a part # and where to get this little peice that goes in the line? Apparently my Ford dealer partsman does not know of this or just wanted tosell me $800 worth of stuff without giving me the magic $2 part.

 

I misunderstood,
I was thinking an "in line" would be in the fuel line. Now I see that the valve is connected to the piping on the module where the fuel line connects. Makes sense now. I took one of the valves off my old but good side mod. and put in place of the weak newer one and is doing ok.

 

I have a 1990 F-150 with 5.0 and dual tanks. When I would fill both tanks full and then run off the front tank I would get cross flow into the back tank and it would overflow. I went to ford and they said that the recall had ended and they couldn't help me that way but would gladly install new pumps in my truck. Went ahead and changed both pump units and so far haven't had the same problem. I will keep my fingers crossed.