I have a '71 142E with the ralley package, and two of my gauges are now not functioning correctly. the temp. gauge always reads c but jumps about eraticly when I first depress the throttle or release it, and my oil press always reads 150 psi plus regardless of what elce is going on. I've pulled all the wires from the sendinfg units to the gauges them selves but can find no error. any guesses?

The oil pressure... did you use the original sensor or the one for the rallye one... cause the old one is only a switch... either on/off.... you need one which can tell the pressure... (big and round...)
Hope this helps.

no, I used a multi-meter on the sensor out put and all seemed well. so I didn't change the sensor. but yes it is the large round version.

It may be reacting to voltage fluctuations as the voltage will jump as the revs pickup.I think all these were meant to run at a constant (8???) volts the regulators were notoriously unreliable. A solid ste voltage reg usually cures it.


Regards


Pete

I should be able to check the voltage at the gauge input and see an even voltage level, right?

Absolutely, if you see the voltage rise to 14 and a bit volts its getting the full charge output. Incidentally this has nothing to do ith the voltage regulator on the alternator, there's a separate one for the instruments.


Regards


Pete

Sounds like your throttle linkages are acting as the ground lead. Check the
grounding strap between the bellhousing and the chassis, as well as the grounds
between your Rallye cluster and the dash panel. Corrosion may have reared its ugly head in these areas.

Cool, I'm on it I'll let you know if it solves it, Thanks