I have a 89 F250 with dual fuel tanks. The rear tank works fine. When I switch to the front tank the truck will idle but when I try to accelerate the engin will hesitate and sometimes even stall. If I am using the rear tank at say 55mph and then switch to the front tank the engin will run like it should for a short time and then begin to hesitate or even stall at times.

If I go under the truck and lightly tap on the slave pump the truch will sometimes run good for 5-10 miles and then begin to act up agian.

Does anyone have any advice on what the problem might be. I really need help on this now because now the rear tank is leaking and I need to use the front tank as the only gas tank.

Thanks for any advise on this.

 

Sounds like a bad low pressure pump in the tank.

 

I would agree.
But when you say slave pump do you mean the pump on the frame rail? I don't know how they are wired, but I would imagine the pump on the rail wouldn't be wired in with the other 2 other then maybe power, but if it will idle you still have power.
So that brings me back to the intank pump.

 

Here is a diagram.



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Thanks for your quick response to my problem. Sorry I did not get back to you sooner on this. I have had to cover for one of my co-workers that became ill and have been overwhelmed with the workload.

antony25 what would you suggest that I should do to check and see if indeed it is the low pressure pump in the tank is bad, short of dropping the fuel tank and pulling the pump?

KCB37 Thank you for the wiring diagram. Yes, the unit that I lightly tap on is on the frame rail. When you say intake pump do you mean the pump in the fuel tank?

Thanks agian, you guys are great!!
kjg58

 

Your welcome for the diagram.
Yes he was talking about the front in-tank pump.

 

I agree that it sounds like the pump in the tank. I had to install a new one on my 88. I described it on my web site. www.winfordr.com

But, I also had a problem with the diverter unit which controls which tank gets the return fuel. Turns out when I was on the rear tank, the return fuel was going into the front tank, causing it to overflow. The device does not have any wires so must work strictly off pressure.

Rather than pay the price they wanted for the new tank for my front pump, I bought a mustang fuel pump and adapted it to work on the apparatus. I don't recommend that path unless you are willing to experiment and fabricate solutions.

Just be careful with all that gasoline and the fumes!

 

Thanks agian for your help. And yes, I will try not to blow myself up with all the fumes.