AC leak detection after pump down

u should use nitrogen and a small amount of refrigerant but if i were u i would convert to r134a its alot cheaper the kit contains 134a-ref. with oil and stop leak in the same can it works great

Thanks for the reply. I would convert but my Keihin compressor is incompatible. As for the nitrogen, I got a price of $60 for a 20 cu ft tank--no idea if that's a good size--plus $18 for the gas. Then over $110 for a regulator :-(

I was considering buying a portable 10 gal 115 psi air tank for $40 from harbor freight and getting it filled with nitrogen. Anyone have any other ideas?