1992 For 250 - fuel issue?

[dhermesc]

My son has a 1992 F250 with the 5.8 engine. He ran it out of fuel (tank ran out on 1/4 - cheap after market fuel pump). We put a few gallon in it and he bled the air off on the fuel rail and it started and ran for a minute and he shut it off. The front tank doesn't work and we were planning on pulling the bed to replace that fuel pump and float combo. He tried to start it yesterday after it sat for 3-4 days and it wouldn't fire. The fuel pump is coming on but he said the pressure on the fuel rail seemed low when he checked for air. Fuel pressure regulator - or has the replacement pump (been in about 1.5 years 20K miles) gone bad already?

 

[Hobo,NC]

What is the fuel pressure, BTW that's a must question to answer. Fuel pressure gauges are cheap you may be able to get one thru a auto parts tool loaner program.

Most all replacement parts are cheap junk. Delphi pumps are the best but even they have their issues with fit being the top issue.

Tanks, these folks have the best the rest are junk and short lived. The next time i have to do mine I am gonna get plastic tanks.

https://www.gastanks.com/GAS-TANKS/departments/1/

Dual tanks the dumbest contraption they ever put on a pick up. 25 years are their life span either way a tank is in your future.

 

[504]

I have put one tank and four pumps in my 97 Chevy 2500. With 100000 miles on it and my Ram has 220000. Miles and I changed the pump because the sender failed. You never know you have a good part till it breaks!

 

[Sprint 6]

Those dual tank setups use a switching valve that switches based on which pump is supplying it pressure. I have seen them fail and pump the return fuel back to the wrong tank, emptying the tank where the pump is running.

 

[dhermesc]

This truck had the rear tank removed when I bought it. I put in a new tank and fuel pump - everything was still there - just full of dirt all this about 18 months ago. Since then the front tank quit
working and once in while he thinks the back tank had had weak moments. I am also wondering if the fuel filter should be swapped. I thought I did it but I also remember buying one for him to install -
and eventually found the new filter rolling around in the back of the truck in the hay and mud - never was installed.

 

[EFV]

Need to hook up fuel pressure gauge to schrader valve on rail.
If pressure is low start with cheap stuff. Check/replace all grounds.
Advice is X100 if truck was a GM product. Ford pumps fail but not
as often as GM ones.

 

[RobCons]

Get a gauge and see what the pressure is. I have a 1992 F350 with the 460 in it which should be the same or very similar setup. My memory might be weak but I think the pressure is only 35 psi. On mine there is no switching valve on the frame. I believe that came later. Mine has check valves on each tank to prevent backflow from one tank filling the other. The tank switching is done with a rocker switch on the dash.

 

[Hobo,NC]

(quoted from post at 03:45:03 11/13/23) Get a gauge and see what the pressure is. I have a 1992 F350 with the 460 in it which should be the same or very similar setup. My memory might be weak but I think the pressure is only 35 psi. On mine there is no switching valve on the frame. I believe that came later. Mine has check valves on each tank to prevent backflow from one tank filling the other. The tank switching is done with a rocker switch on the dash.

I did a 96 a year ago the check valve was made in the fitting where it connected to the pump at each tank. I dunno when they started ended that. It was the first one I had paid attention to like that.

I have had bad new senders are the sender hang up after install so make sure they are operational after I put the pump in. I try and find away to manually operate the sender arm like going thru the vent valve hole in this pix. Ford pick up tank.

 

[Northvale PA]

Try replacing the fuel relay switch. $15, so cant go wrong. Might have failed coincidentally. I stuck a new fuel pump on mine. Nothing. I pulled the wires off the pump and hooked a battery charger to it. It ran immediately indicating relay bad. Good luck.

 

[MF#1]

Several years ago I bought a 1995 F250 at a farm auction and the front pump wasn't working. I got a rubber mallet and smacked it a few times and it started working, been working since. Before I spent a penny on it I would give BOTH tanks a few whacks and see if it helps. Maybe some crud from the rear tank lines got lodged in the lines or pump since you found the filter in the bed? And yes, new pumps can fail too given the junk that is sold today. Good Luck with it, they can be a royal pain to deal with.

 

[UncleTom]

You can check the fuel pressure regulator by pulling off the vacuum hose on the regulator and see if there is fuel present in the port. If there is fuel the diaphragm is shot and leakingsucking fuel into the engine and wont maintain proper pressure in your rail. And we love follow up as to what fixed it.

 

[dhermesc]

The rear pump is working - you can hear it whine on when you turn the key. I was watching some videos on how to check pressure and how vacuum leaks can affect the pressure switch. It seems strange how reliant Ford was on vacuum activated controls even in the mid 1990s. Check that and if the electric pump is generating enough pressure to even feed the injectors. This truck has been used hard and my son - being the product of my wife's side of the family likes to drive on the last 1/4 tank of fuel all the time and never fixes anything until it is broke and he needs it to use.

 

[Hobo,NC]

Don't put much faith in a leaking pressure regulator diagram causing the pressure to be so low it will not run. I have never see it happen and doubt I ever will. If it did affect fuel pressure to be that low the pump is defective and not able to build max pressure.

The main piece of info needed is the fuel pressure period! Its the first tool you hook up and does not come off till it fixed.

 

[RobCons]

I had to replace the check valves on my F350 awhile back. Had to get them from a dealer and they said the valves are no longer available. They had 4 on the shelf so I got all of them. They were not very expensive.