I have been told very good things about enviro-safe. Yes it is a hydrocarbon, and it only requires about 1/3 the amount of r12.

The leak was because of a crack in the cap and the shrader valve (spelling?) was stuck down a little too. Finally found that when I got a new cap it stopped leaking, then replaced the valve. The system was never fully empty or exposed, it was a very slow leak.

I plan on charging with this stuff, tinting the windows as dark as legal, and see how that works. In the summer here, if I leave the car out in the sun for more than half an hour, its going to be a crappy ride - I hope to at least semi-fix this.

That makes sense with the responses I received. I bet some of the oil was lost when evacuated, and then I just added a can of 134 without oil, causing it to be a little low. Probably damaged the compressor some

Since my original post I went ahead and ordered some cans of the enviro-safe. With my order I got some cool oil testers - you just screw them into your low port, have your compressor running for 10 min, push this button, and it tests your oil. Tells you if you have enough or are low, and also tells you the condition of the oil... pretty cool!

What do you think?

http://www.es-refrigerants.com/products/w/id/166/t/pittstop-r134a-oil-checker/details.asp