i just bought a supco vg64 miron gauge. i hooked it up to my vacuum pump as i ran it the bars where showing it was pulling down , after about a half hour still showing above 12000 microns i changed the pump oil before i started. then i took my gauges off closed pump valve still the same after an hour . dous any one know if there is a way to tell if there is an air leak using several fittings at this time
any help would be appreciated