[British-cars] [TR] Voltage Stabilizer for TR3

[Randall]

> Still no improvement, so I wrote to BPNW and they say I should have a
> Voltage Stabilizer pn=148876D mounted behind the gauges.  

They are wrong, assuming you are talking about the stock TR3 setup.  The
voltage stabilizer started with the TR4 gauge set.  The TR3 used a
"balanced" fuel gauge that does not require a voltage stabilizer (and will
not work correctly if one is installed), while the TR4 used "hot wire" fuel
and temperature gauges that require a stabilizer for proper operation.

BTW, the fuel sender is the opposite, electrically, between TR3 and TR4.
Apparently they don't know that.  My next step would be to check some
resistance readings to be sure you have the correct sender.  The proper TR3
sender will read nearly zero at empty and somewhere between 70 to 100 ohms
(I forget the number offhand) at full.  The TR4 sender is just the opposite:
nearly zero at full.

You might want to read through Barney Gaylord's excellent article at
http://mgaguru.com/mgtech/electric/fg_06.htm

Although not quite identical, the TR3 fuel gauge is very similar to the MGA
gauge.

-- Randall