TR2/3/3A TR3B fuel gauge

[TFB]

My gauge goes from E to slightly above E when ignition is turned on.I think I have about 4 gal. in tank,so thought it should read higher.I started to check sender and try to move float when I disconnected the gauge wire from the sender and gauge now reads full.

Is this right ?
Thanks
Tom

 

[Geo Hahn]

Here's a useful site -- it's for an MGA but basically the same gauge (ohms may differ slightly).

https://mgaguru.com/mgtech/electric/fg_01.htm

 

[TR3driver]

Yes, the TR2-3B fuel gauge works backwards from the later units. Disconnected from the sender, the gauge should read past full.

For an easy test, you can just stick a bent coathanger down the filler hole, hook the sender wire and pull it up.

One thing to check before you go pulling the gauge apart (as in Barney's excellent article above): Is the gauge securely grounded? Again unlike the later TRs, the TR2-3B gauge needs to be grounded and I have found the factory ground through the mounting clamps to be less than secure, especially if the panel has been painted. I added a small ground jumper from the mounting stud to the ground tie point on the back of the panel.

 

[TFB]

Thanks Geo for link and thanks Randall for info.Will continue to investigate.Thought I may have wired gauge backwards.
Thanks
tom