1982 Chevrolet Silverado fuel gauge

[N44252]

I have a 1982 Chevrolet Silverado club cab dually long bed with the 454 cubic inch engine. It has the twin gas tanks with the electric transfer switch on the dash. The fuel gauge is not working properly. Does anyone have any idea on where to start to trouble shoot this? The factory manual trouble shooting algorithim mentions a testing tool which has to be a variable resistor. But what is the resistance (ohmage)? I would appreciate some help with this one before I start removing gas tanks. Thanks

[bradrhale]

it depends on how full the tank is. the amount of ohms is a measure of the tank. try the sending unit by making sure you have voltage to it and a good ground. what exactly do you mean by not working properly??

[N44252]

Thanks for your response to my inquiry. For starters I am not completly sure that the shuttle valve is actually switching the tanks. It makes noise when changing from left to right but is silent when going the opposite way. The gauge reads full regardless of which tank is selected and I know that both tanks are not full. I can see the fuel gauge needle quiver very slightly when pressing the tank selector either left or right. The gauge worked when I bought the vehicle about 6 months ago. Like I said in my first inquiry, the GM manual mentions a tester which I would think is just a variable resistor. But what is the ohmage? I noticted that the fuel gauge sending unit on my 1975 Buick Skyhawk is stamped 90 ohms. Thus, I would think a 1982 Chevy truck would be similiar. What are your thoughts on this? Also are the sensors prone to malfunctioning? And, if I need a new electric shuttle valve where do you think I could find one? Thanks N44252

[mrjohnwayne]

I think it is 90 ohms on the trucks also. The sending units on those trucks are prone to failure after years. As for a new valve the dealer or maybe napa, autozone, oreillys etc..

[bradrhale]

would that be 90 ohms at full or empty??

[mrjohnwayne]

full I believe