MG Car Repair: 79mgb voltage regulator, voltage stabilizer, gauge reading

Question
Where can I find it on my '79MGB. I found the voltage stabilizer  behind the dashboard, in hopes of correcting a strange fuel gauge problem. I can't find it in my Haynes manual.

Answer
Hi Howard,
The voltage regulator for the alternator is inside the alternator and can be easily checked by just testing the voltage of the battery (post to post not cable ends) (12.5+ volts) and then start the engine and put the RPM at about 1500 RPM and read battery voltage again (post to post 13.8v to 14.5v)
The voltage stabilizer supplies the power (10v) to the fuel and temp gauge only.

The voltage from the alternator and / or the stabilizer can affect the gauge reading but they will affect both gauges. Not just one.

The rough test for the fuel gauge is to turn the key on and remove the sending unit wire and watch the gauge and it will deflect all the way and then touch the wire to ground and the needle will deflect all the way in the opposite direction. Also you need to test the ground (black wire) at the sending unit to see that it is a good ground. A final test is to remove the sending unit and connect both wires to the sending unit and operate the arm with the key on and watch the gauge to see that you get full deflection on the gauge scale.

You need to tell me what a "Strange gauge problem" is.

Howard