I have an heathkit audio generator mdl ig-72 powered thru an isolation transformer but I'm measuring 160vac from chassis to earth ground the generator has its own power transformer.

Have you been shocked? Probably just stray capacitance if you're measuring with a DMM or VTVM. If you have an analog (mechanical) voltmeter, which has lower input impdedance, try that.

Otherwise, temporarily connect a 50K +/- resistor from chassis to earth ground, and then measure the voltage with your DMM.

:I have an heathkit audio generator mdl ig-72 powered thru an isolation transformer but I'm measuring 160vac from chassis to earth ground the generator has its own power transformer.