The only thing I dont do is AC/Freon- I dont have an evac machine.

You should spend the $90 and have someone evac that, test for leaks- then fill with the proper amount of freon BY WEIGHT. Add dye. See how it goes. Maybe add $50-75 for the freon you will need.

FWIW the tolerance on the fill is like 1.65lbs +/- 0.02lbs