TR2/3/3A TR3A Fuel Gauge

[CaptRoy]

Well I now have the fuel gauge working on the TR3. I received the sending unit from Moss hooked it up and it still didn't read right. I sent the gauge and sending unit to Calif had the gauge rebuilt and calibrated with the sending unit. They arrived today I changed them out this evening. I changed the gauge first and then replaced the sending unit after I hooked it up and made sure it worked. I had to pull the glove box to get to the fuel gauge. The entire job only took 2 hours including putting the tools up.

I have never had panel lights and now I know why. There are no light wires hooked to the gauge. The PO put in a new wiring harness but neglected to wire the lights on the gauges. I think it is the blue/white and I just need to run it in series from the panel light switch...Does that sound right..

 

[Banjo]

The panal lights on a TR3 are mounted to the dash panal. THey shine through "windows" in the body of the gauges. There are only 2 of them for the 4 gauges on the center dash, and are situated on either side of the switches, mid way between the top and bottom gauges on each side.
The Tac and speedo each have two bulbs on the same type fiberboard socket that the panal lights use.
It should be a red wire with a white tracer. The bulbs in the Tac and speedo ground through the gauges, and there should be a ground wire captured under one of the thumb screws on each. the center dash bulbs ground through the panal as they mount in the rings that are part of the panal, and that panal should have a ground wire on a bullet connector attached twards the center of the back side.
Blue and white wires are the headlight circuit. Don't tap that wire.