Dennis, I've been out of town and just checked the mail, so thought I'd
respond to your earlier query about calibration of your fuel gauge. If you
haven't already been informed, there is a way to calibrate which involves
physically adjusting (moving) the span and zero coils that are used to
"drive" the needle pointer, it's all based on magnetic strength of the
coils. I don't have a specific procedure, as I did mine by trial and error
using a potentiometer to simulate the sender, but you can do the same just
using the sender to supply a reference signal to the gauge (actually,
probably a preferrable way to go, since you don't have to know the
resistance span of the sender). Be sure to ground the case of the gauge
while you do this adjustment, as this is part of the circuit. I just moved
the coils around until the zero and span were correct and the gauge was
linear in response. Additionally, as I recall, there is a shunt resistor
inside the gauge that might be bad. I don't remember the resistance of it
now. Got the old-timers disease, crs. Perhaps Dan M. can fill in the
blanks, as I'm sure I've forgotten something. Having said all this,
however, I would not recommend this procedure unless you feel comfortable
working on really small wiring, as the circuit is fragile. Good luck.
Richard
>From: Dennis Lambert <>
>
> Listers,
>
> I have finally got the wiring on my TR-3A complete. When I turned the
key
> to the 'on' position, the fuel gauge immediately showed 1/4 full - the
tank
> is absolutely empty. I have measured resistance at the sender, and have
> about 1 ohm at empty (float all the way down) and about 82 ohms at full
> (float all the way up). It appears the sender is OK. When I short the
> sending wire (green/black) to ground, the gauge immediately goes to 1/4
> full, and stays there. I suspect the gauge to be bad. Is there a local
> shop that can repair a TR fuel gauge? Or, has anyone disassembled a TR3
> fuel gauge and successfully repaired it?
>
> As always, I welcome and appreciate your collective knowledge, wisdom,
and
> experience.
>
> Thanks, Dennis
>
>
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