Greetings,
Today I had my 62 gauge cluster out. I restored the odometer with a donor first and second worm and numbers, so that’s good. Remaining gears were good and the number roll was hanging up.
I disassembled and cleaned the headlight switch, so the rheostat works very well now.
I opened and cleaned dust out of the gauges, and this is where the day turned badly.

What’s bad is my fuel gauge now sits at empty with a slight twitch at power on and the temp gauge flies up to max. Both worked just fine before and quantity checked out at the petrol station and the temp was spot on, confirmed by IR. All wires were labeled before disconnecting. Light bulbs are all operable and respond equally to the rheostat.

The fuel gauge is original recipe. Confirm there should or should not be insulation inside the gauge cup between the gauge and the cup? The gauge cluster is well grounded. I spent most of the evening troubleshooting the water temp gauge, so I haven’t been able to start grounding and shorting the fuel gauge to test.

The temp gauge is a new repro style. Confirm there should or should not be insulation inside the gauge cup between the gauge and the cup? Sender resistance checks out, ground on the block and cluster is good, and resistance of the blue wire to ground is equal to sender to ground. With a jumper to the sender, the gauge jumps to max at power on. Sender resistance increased as time passed.

I fear I destroyed the gauges trying to fit everything inside the gauge cups, or something in reassembly isn’t proper.

Thank you.

 

It sounds like you have managed to ground the sender terminal on each gauge. Neither the power terminals nor the sender terminals should ground out. The gauges ground through the back housing. I know the earlier corvettes grounded through a bare spot on the back housing but I can't remember how a 62 gauge grounds but I would be surprised that it grounds differently. You should always test your gauges with an ohmmeter long before you apply power. Disconnect all wiring and connect the ohmmeter from the back housing (or the frame of the gauge if it out of the housing) to the power terminal where the pink wire goes. You should read a few tens of ohms. Now test from the frame to the sender terminal. Again, you should see a few tens of ohms. This applies to both gauges. I suspect that you are reading 0 ohms from the sender terminal to the frame. I'm betting the terminal studs are not insulated somewhere and are touching the back housing.