Gas gauge: With key on, use a screwdriver (or a short piece of wire) to short the center screw on the sending unit to ground. Gas gauge should read empty.
Now take the wire off of the sending unit. Gauge should read full. What does yours do?

Ammeter: One side should have only the battery wire coming from the stomp starter switch and the power wire to the horn. The other side should have all others. With the key off turn on the headlights. If the ammeter shows a charge swap all wires from one post to the other on the ammeter.

No leaks on the floor: Are you sure there is oil in the engine? wink

In case you don't have a wiring diagram CLICK HERE.

Last edited by Bill Hanlon; 04/30/2026 10:23 PM.

'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12
'52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.