Performance Indicator Gauge

Well I used my HVAC vacuum pump on it yesterday and the needle didn't move. The pump pulls 29" so it should have done something. When the vacuum was on it the coiled arm did move slightly but not enough to get the needle off of the needle rest stud.
I put it back in the dash and gave up on it. It lasted 53 years so I cant complain. I guess it'll be something else to look for at swap meets.