No other filter and I told ....................

 

Yes yes, Glenn, I was expecting that.

 

Sorry, mobile phone double post.

I guess here's where I am at now. Do I assume that I have a bad fuel selector valve, seeing as how I lost my front tank use about 18 months ago and I can't find anything wrong with it? Is it possible the fpr is bad now too?

 

No I dont think so, Why it coud be bad?. Maybe clogged. IDK

 

You can try blowing air back through the supply line.

Here is a thread that might help ... https://www.ford-trucks.com/forums/1...l#post12149701

Specifically posts 23-24 on the fix.

When you switch tanks does the fuel gauge level switch? That would be an indication the valve is actually moving. Did you replace the small length hoses (2) when you did the fuel pump or are they original? Reason I ask is there have been cases where the owner replaced them but with poor quality and the pump sucking action actually collapsed the hose preventing fuel from flowing.

Just thinking out loud here ...

 

I wouldn't assume anything at this point. I would try and run it off a length of hose in a can of fuel. Swapping parts that may not be bad is an expensive gamble.

 

Yes, the fuel gauge does change when I switch tanks, and I can both feel and hear a noise at the tank selector valve too. Although, I suppose it could be making noise and doing nothing inside. I replaced my hoses the last time that I replaced my fuel pump, they don't seem to be worn or anything, and they are rated for fuel line, but I suppose I can change them again.

Assuming that I hooked the line up to the supply side of the pump (the hose on the top of the pump, drivers side), it sucked the fuel that was in the can with no problem. I would think that if there was air in the line, it would have worked itself out by this point, I have had it running 3 or 4 times now for about 2 to 3 minutes each time, but each time I open the fuel bowl and it is half empty.

 

Running it off a can of fuel tells us if it is a pump issue, or if it is an issue with the plumbing, switch, tank pickups, etc.

Also, for what it is worth, I would put the return line into the can as well just in case there is an obstruction in the return somewhere that is not allowing the air in the bowl to be pushed back out of the system and to the tank like it should. The air should go straight to the tank when you start the truck. It should go out through the FPR and down the return lines and go back to the tank. The fact that it is still only half full seems suspicious to me.

 

Ok, I blew out the supply line and replaced the hose for it. I got into the truck and it started up real nice like. I had 45-48 psi on my fuel pressure gauge. When I revved the engine I saw moderate increases in fuel pressure, up to about 55-60 or so. I switched between tanks and saw no drop in pressure. I let it sit idling for about 5 minutes, then the pressure dropped off again and it died and would not restart. I pulled open the fuel bowl and it was less than half full.

 

Sounds to me like you are picking something up in your tank and clogging the pickup or a line. You blew out the line and it cleared up until you picked it up again and clogged the line again.

 

Yeah, I will try to blow the line again and restart.

 

Have you thought about simply testing the pump.. ?Like has been suggested ?....
Its rare that a poster works as hard as you to not do the recommended testing ....IF the truck runs from an alternate source ,. its either the valve , or the tanks . The tests are up to you ...

 

Rick, refer to post #82, I did test the pump, like suggested, and I've dutifully followed through on pretty much every suggestion that people have made and posted the results. I know it can get tedious reading through long threads, so I don't blame you for overlooking a few.


So, with that out of the way, the beast is back to life FINALLY. I removed the lines from the selector valve and blew them out from that point. I would like to point out that if anyone else does this, open your gas-cap or you will pressurize the tank when you blow the return line and it will shoot fuel out of the supply line. Then I took of the supply and return line (as suggested) from the pump and fpr and blew them out as well with them disconnected from the valve. I buttoned her back up and it started after a few cranks. Fuel pressure when up to a solid 50psi and now both of my tanks work instead of just the back one.

I would like to say thanks to everyone for all of their help, suggestions, expertise and encouragement. Through frustration and desperation, I took this thread in many different directions, but you all put me back on course and kept me focused on finding the problem. You all deserve a special thanks (particularly Glenn), if you're ever near El Paso, I'll buy you a beer and put your favorite song on the juke box.



Best line of the thread!!!

 

I'm glad to hear it is running again. I hope it stays that way, but I have my doubts...

Blowing the lines out doesn't really fix anything. If there was something in the lines it came from the tanks. And unless it was blown out of the lines and onto the ground, it is still in the tanks.

I hope I am wrong, and I really am glad you have your truck running again.

 

IIRC he checked one of the tanks and was clean IDK. But you are right, where did the clog material or whatever, come from? Maybe from the other tank
Anyway, glad that is running now and I also hope that your truck runs well since now.