duckhunter

Had to replace the outer fill hose for my rear tank,now it seems there is air in the line,let the truck idle for 10 min. and tried to get the air out by bleeding the system on the injector bar,did it 3-4 times still dies if I put my foot into it it will idle fine,up to about 1500prm's then just starts to sputter.

HELP...

THANKS

wde3477

Welcome to the site!

Model, year, engine, dual tanks?

Have you checked the fuel rail pressure? Typically, if you have air in the fuel lines, such as from a fuel filter change - cycling the key from Off to On several times (10-20) will purge the lines.

duckhunter

Thanks will give that a try,

96 f-150 351,not sure what you mean by (dual tanks?) there is a frount and rear tank.

But do know when I purged the injector bar on the front tank,got about 10-12 tablespoons of gas coming out,when I did it with the rear tank it just kind of spitted out about 1/4 of what I got out of the frount tanK.

Also when I replaced the outer hose on the rear tank I did not remove the fuel lines,so really not sure how I got air in my lines,thinking now I may have a bad filter.??

THANKS

wde3477

ah, then you have dual (two) tanks. From your description, it sounds like there may be a problem with the rear tank - maybe or maybe not related to the work you've done.

Do things clear up when running on the front tank?

Some things to check - rear tank is not venting properly causing a kind of vapor lock, rear tank pickup screen is plugged, rear tank fuel pump is not working properly, tank selector valve has a problem.

The inline fuel filter should be common to both tanks - so would expect the same issues no matter what tank is selected.

By 'outer hose', are you referring to the tank fill vent, or the fuel return line from the engine?

duckhunter

Yes tank fill vent,had a pin head size hole but gas was running out.
Your right tanks share filter,thanks I should have known that...
Yes when running off the frount tank evert thing is fine.
Tried turning the key on and off 25 times can here the pump running 3-5 seconds.Still the same.
Played with the frount tank pump only ran for a max of 2 seconds if that.
Don't think it is the selector valve,becuse it seems to be working becuse when on the frount tank every thing is ok,dose that sound right?
Any ideals what to do with out dropping the tank?

THANKS

Fast Hampster

Perform a fuel pressure test for both pumps and post the results

duckhunter

Got a buddy coming by this weekend with a gauge,to check pressure.

Another thing is the sound(pitch)the fuel pumps make the frount one that works right is a high pitch sound,while the rear is a deeper sound,does this sound right?

Also tried running the truck with thr rear gas cap off,made no difrence,do not know if that matters or not just trying to find out what is wrong before my buddy gets here.

Thanks

Good old Bill

If my memory is functioning fully, seem to me there were issues with the selector valve not switching. The electrical portion would work but the actual fuel flow portion would not change position to allow flow from the opposite tank.

duckhunter

Bill,I the valve is a pressure switch,so no electric to go bad,it think.

Did a fuel pressure test this morning,30 lbs a iddle but as soon as I put any pressure on the gas peddle it drops to under 10lbs,so the bad news is I have to take the tank out again,just my luck just got done filling the tank.

Thanks