Ok, well the gage uses 100 uA DC to get you 60 Hz on the meter, so if you have a DMM capable of measuring micro amps DC, disconnect the 2 wires and measure across. The wires go directly from the output of the transducer to the gage, so if you are 100% positive that your transducer is good, the only other possibility is a bad gage of an intermittent connection / broken wire.
You can also take your old transducer and put a cord on the AC input and plug it into a wall outlet and put wires from the DC output of the transducer to the correct polarity of the gage, or you can also test for DC uA output of the old transducer.