How do I diagnose an inoperative gas gauge on a 1947 Chevrolet 3100 pickup. It was working but then it just quit and the needle registers full all the time. Thanks

 

Welcome to the forum.

Check the resistance of the sending unit and remove several gallons of gas and check again. If it doesn't change then it's probably the sending unit. Also check the wiring between the sending unit and the gauge.

Also post in the pickup section of the forum to get more views.