'92 Olds 88 no air from vents and compressor engagement issue

[atikovi]

Car has been sitting 4 years and there is a sticker saying it has been converted to R134 back in 1999. Found the system empty so I vacuumed for 15 minutes and checked 15 minutes later. Gauge still around -30. Vac another hour and charged with 1.92 lbs as the sticker said. Got in 6 oz but compressor only came on a few seconds even though low side over 60. Jumped the clutch and got a full charge in and air blows fairly cold, but coming from the defroster and floor outlets, not the dash vents. It has the manual controls. Assume this is a vacuum leak. Where do I check? Will deal with compressor later once airflow is correct.

[atikovi]

The vacuum tank was leaking. Sealed it up and now air flow is normal. Compressor still not working properly. Did get it to work for 5 minutes last night before getting home, but nothing this morning. Possible relay contacts corroded?