ok im having a few problems. 87 f250, 460, carbed.

gauge pegged on full on both tanks. my temp gauge doesn't work ether but i dont know if that has any thing to do with it .

some one has replaced the selector valve and they cut and spliced the wires (anyone have a diagram for a 87 )

i dont know if the valve even works,it might be stuck on one tank. i had my hand on it while someone flipped the switch and i couldn't feel/hear any vibration or sound.

any clues to why my gauge is pegged and is there a way to tell if my valve is bad?

 

Your truck uses a different setup than mine. I was typing a response, checked my Haynes Manual, and had to delete it all cause Ford did something different with the switching for EFI and carb'd trucks. Some of the carb'd trucks use the setup I have, but your truck does not.

The one thing I can tell you off bat is that the temp gauge can only be related if the cluster is no good. Otherwise you need to locate your coolant temp sending unit and replace it.

 

Don't you know that's just going to get you into trouble?

Try giving your tank selector switch a check. My father had an issue w/ his old beater that the fuel gauge would peg waaaaaaay past full, and he traced it to a bad selector switch. But this was an '84 pickup too, that had a manual valve for physically switching the draw between tanks, leaving the switch just for gauge purposes.

You may also want to make sure the gauge grounds are good and clean.

 

i just found this diagram and it says the valve should be wired up as

1 brown/white
2 red
3 drk blue/yellow
4 yellow/white
5 yellow/lt blue

my truck has abcde instead of 12345 but im guessing its the same.

my truck has

1 drk blue/yellow
2 yellow/white
3 yellow/lt blue
4 brown /white
5 red

would the truck even run with wiring this far off? or am i not reading this correctly?

 

There have been a few threads on this recently.

Subford has some excellent diagrams.
https://www.ford-trucks.com/forums/9...ml#post8659288
https://www.ford-trucks.com/forums/9...or-wiring.html

 

ok thanks, i tried switching the wires around and it made no difference. i guess i will get a new switch and see if that works.

 

I have a mechanical fuel pump...
When I couldn't switch tanks it was the switch in the dash.

Surprised to see all these threads lately. It says a lot for the carbureted 460 that there are still so many on the road.