I wish you would of did o-ring swap on the A/C when you had it empty ... I'll bet its leaking at the pump adapter o-rings ..Is the adapter dirty where the A/C oil has leaked ?...You can 'see' A/C leak if you know what your looking for ... As a mechanic by trade ...I have come to see a mess of info out there is BS in the car world .. ..A shop owner I know shop truck has had R134 put right on top of R12 just to see the out come ..That was ten years ago..LOL...Still going strong...Would I say try that ...No...LOL... I could go on for hours on the sh*&t we have tryed and pulled off...