Fuel Gauge/Dual Tank problem

[Barraphernalia]

85 silverado SWB
Dual fuel tanks
Big fuel gauge

Not sure what to think here:
A couple of months ago, it started getting really hard to switcg from one fuel tank to the other. I would have to flip the switch many times to get it to switch. So I decided that maybe something was on the verge of going out on me and that I would just use the driver side tank from then on. So for a couple of months now I haven't touched the switch.
After filling up this morning, my fuel gauge didn't move. I don't know why this would be related to the dual tanks, but I just thought maybe I should mention it. I tryed restarting the truck a couple of times, and then I thought "what the @#%$" and flipped the switch a few times. Neither did anything. So now I've got a full tank of gas that reads as an eighth.
I've got no idea where to start. Any help is greatly apprerciated.

[roundedline]

If you can bypass it, check around the swith.  If that works, pull the switch appart and clean up the connectors:

Chris Lucas
www.73-87chevytrucks.com
www.captkaoscustoms.com
Project Su
Jimmy 2WD Project

[1973gmc]

A couple times after a fill up on my truck, the fuse would blow for some reason. So check your fuses, I have dual tanks as well and I swear they react differently as well. I replaced fuse both times and gas gauge works again. Hasn't blown again for a long time now.

[79ChevyK20Guy]

CHeck your voltages at your fuel tank sending units, it is an electrical problem so start there, if there is no voltage check at the switch if no voltage check for a blown fuse. I have dual tanks on my 82 and did away with the electronic selector and replaced it with a manual tank selector from a boat. The gauge still works for both tanks as well because the is a switch that moves inside the selector from the boat. The only down side is it makes it look like it has a manual choke because of the way the cable is designed.

[joesgarage71]

Be sure you have good grounds at the switch and for your sending units.
Steve