1955-56 Senior instrument cluster

Posted by Craig Hendrickson On 2016/9/6 10:45:11

Due to my "minor" setback on my Panther project, I'm going to have to use an original Packard instrument cluster. I have 2 1956 400 clusters, one removed and on the bench and the other still in the parts car. Does anyone have experience testing the gauges? The speedo is not a problem since one can drive it with a variable speed drill, but the electric gauges (fuel level, oil pressure, ammeter & temperature) are a little more problematic. I have a good digital multi-meter, a good 12V battery, alligator clip wire connectors, a potentiometer and I am comfortable around electrical devices. But, what I'd like to know is:

1) Off to full scale resistance of the individual gauges.

2) What resistance is needed to test the ammeter?

3) What exactly does the "Instrument voltage regulator" on the lower center back of the cluster do?

4) Is there a good way to test the oil pressure gauge sender short of hooking it up to a running engine?

5) Any helpful hints.

Craig