AC system questions

I took the AC evaporator out of the car to try and find a leak. It is never in an easy place to get to is it? I couldn't find any damaged area as I had thought but instead I found that I had neglected to tighten a factory assembled fitting. It was tight but I turned it at least 3 rotations to snug it up. The system worked a little bit(never really cold) and held a 30 psi vaccum, but now the system has no charge so I took it apart when I spotted oil dripping from the blower fan. My question is how to test the evaporator out of the car? Do I need to pump it up to 100 psi and see if it bleeds off. Do I need more pressure? , less pressure? I am really new to the ac world. I just don't want to put it back together with out testing it.
 

Jim Dewar

Supporter
Dean, Simply evacuate the system to -30lbs. vacuum and let it sit overnite. If it holds your ready to recharge.
 
Dean
The evaporator should see about 50 or 60 psi when the system is idle and about 35 or 40 when running so plug one end and hook up a regulator with air pressure and do the old inner tube trick by submerging it in a tub of water...sounds hokey but it works. Diagnosing a leak in the evaporator on the vehicle is really difficult so make sure of its integrity before re-installing it.
Cheers
Phil
 
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