Cores will always slow down an evacuation, but unlike a residential/commercial there is not a lot of volume to a MVAC system so we usually do not worry about it, at least I don't. I also figured with such a small system, who cares - but evidently that's not always the case. And yeah I'm looking for...

I almost forgot to post a follow up - thanks for your help Charged in a few psi of refrigerant and sniffed - there was one leak, on the low side service fitting. So I went to replace the valve, and as I removed the core - the residual pressure shot some snotty aerated looking oil out of the fitting....

I can isolate the manifold, and/or between the pump and service port. With the manifold connected to the service port(s) and high and low side valves are closed, it pulls deep vacuum quickly. Additionally when I isolate the system with and without manifold it quickly gets down to 100 microns. I gues...

Hi all I Installed a new Delphi compressor to replace the original one that had just started to leak oil (still drained 2 oz out of the old one after removal), and I'm having difficulty pulling vacuum under ~9000 microns. Shut off the pump and isloate the system and it decays off to 45000 or so, but...