Ok guys anybody tell me how this thing works electrically, mine broke when i pulled the motor out of the 90....i just bypassed it but now my gauge does work XD! Can you tell me how I can get the gauge working without the FSV. Greywynd you probably have the wiring diagram for it.

 

This the fuel selector valve? I'm guessing you have to figure out which wire is the float from the tank you want to use, then hook that up to the wire that goes the gauge.

 

Yes the Fuel Selector valve, I got plenty of fuel in the tnak right now(17 gallons, i kept track)...but sheesh i already ran outta diesel....talk about embarrassing.

 

If you want the fuel gauge to work for one tank only splice these wires together:
(1986 wiring diagram)
Front tank: Dark blue/yellow and yellow/white

Rear tank: yellow/light blue and yellow/white

Should put you back in business....

 

How did you find that out Chris? I am lost...can you post a pic of the wiring diagram you have possibly??

 

2nd row from top (B), right hand side, is the diesel selector valve.

 

Thanks john, but its not working....

 

While John's is layed out differently, all the wire colors are the same....

I haven't figured out how to upload the diagrams without shrinking them so small you can't read them....

 

the basic operation of the selector valve is that 2 control wires switch it from one tank to the other, and while moving the fuel valve, also moves a switch for which sending unit is being sent to the gage. therefore, a leaking or damaged valve that has been bypassed could still be used with stock wiring to control the gage.
for bypassing it, i would suspect that maybe you pulled the gage wire from the wrong tank, and are reading the empty tank

 

Use this site, should do the trick.
www.photobucket.com/

 

Snuff, i upload everything to photobucket. :/ Not sure why but it shrinks it every time....

 

I have a 92 f250 7.3 idi with some turbo kit on it when I bought it. On my way to work I flipped my selector switch to the rear tank and the truck instantly died and the fuel guage reads full on both tanks. I think it has to be the selector valve it fires up for a few seconds and dies right out starving for fuel. It also had another problem when i bought it and first flipped that selector switch it wouldnt start unless it had over a half tank in the tank you wanted to start on, which leads to thinking it has to be the selector valve. It cranks for about 10 seconds on either tank below half then fires up on both tanks at the same level. If the selector valve is screwed up couldnt it mess with the reading? All the problems point there. Anyone else had anything like this happen?

 

Sounds like the selector valve is sticking. You can try taking it apart and cleaning it. That has solved many problems for alot on here.

 

Yeah, it was definately sticking it fired right up today. 120 Bucks ill just get a new one