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TR2/3/3A Can a TR4A fuel gauge be used in a 3A?

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Sure, just a couple of things. Do you have a voltage stabilizer or can you get one, it will read high otherwise and will look a little out of place, just use your convex lens and all will be fine.
I have a full set of gauges somewhere, I know the temp is broken, but could be a good buy for someone, they have the convex lenses.

Would not break the set for one gauge and surely there are a lot of them floating around.

Good luck. Wayne
 
You'd have to use the 4A sender as well. The tr3 sender works backwards to the later ones.
 
Good point, I did not know that.
Could the wires be reversed at the gauge?

Wayne
 
Wouldn't fix the problem. The TR3 sender gives a low resistance for empty, while the TR4A gauge will show full for a low resistance.

Basically, the gauge went from being magnetic to thermal when the TR4 was introduced.
 
That kind of takes care of the swop.
Karl, if you go the route and need a sending unit, I'm sure I have a couple, they do have the plastic floats with them. Seems like a lot of trouble, but you do what you have to, sometimes.

Wayne
 
I'm still in the process of finding out why the fuel gauge needle dosn't move when I turn on the ignition (1/2 tank of fuel) before I go the 4A gauge route but thanks for the sender offer. I might try the test that Randall posted recently to see if I can get the original to work. I put a new wiring harness in the 3 and everything works great but the fuel gauge. Haven't had a working fuel gauge for close to 20 years.lol
 
Understand, the '37 had its own stick with marks for how much. LOL

Wayne
 
90% of sidescreen fuel gauge problems are poor or nonresistant grounds. The factory provided the ground thru the fuel gauge attachment bracket, which seldom if ever was adequate. The fix is a dedicated ground. Clip a test lead to the fuel gauge stud, ground the other end anywhere. If it works, make it permanent. Also, a properly installed fuel tank is not grounded. Be sure there is a wire running from the tank sending unit to ground.
Frank
 
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