1971 Fuel Gauge Help
 

Just got this baby home and the only problem she has is that the fuel gauge doesn't work. Previous owners have said that they have replaced the sending unit. I have removed the instrument panel in attempts to Ohm out the gauge itself, but cannot get behind it.

Any suggestions or tips? Do I have top replace the whole instrument cluster?
Thanks in advance for your help!

Dave

First, ground tan wire in trunk/body = Empty
Second, use ohmmeter and test the tan wire referenced to ground for conductivity
This wire goes to the s/unit through the body harness.
Should read somewhere between 0 to 90 ohms, depending upon fuel level.
No continuity, check ground wire at s/unit connection to body ground and redo the connection.

Once you have an ohmic value, then to the gauge.
You can ohm out the gauge - ohm power going in to gauge
ohm gauge to ground & power to tan wire.
All three should have some resistance.

Remember, gauge is an indicator, not calibrated to any extent.
If 1/4 tank shows, then fill tank and make mental picture of gallons to gauge.

Thanks Everett,

I will try these measurements. I'm assuming that I have to drop the tank to get to these wires in the trunk/body? Wires are to the sending unit, right? Pardon my ignorance... and thanks a ton for your help!

Dave

No, should be in front of the tank - you'll see.
On tan wire, start at cluster connector and work your way back.
Body connector on drvr kick panel.
Another connector through trunk floor by latch.

You're welcome