Hope you have your nomex suit and fire extinguisher handy, folks around here have some strong opinions regarding a/c sealers. Main objection is the sealer can activate in, and clog up, the refrigerant recycling machines which shops are required to use these days. For this reason alone you will find many professionals that object to them. Using one may limit your ability to get the cars a/c system serviced in the future.

That said, I've had some firsthand experience with sealers. Cryo-seal is the two-part kit with the dryer then the sealer, correct? I had near perfect results using that on a 124 to seal an evaporator leak. The car went from 1/lb month to no detectable leak with a single treatment. Unfortunately the compressor wore out after a year, so I only have that much data. But it definately worked. Don't skimp, change the dryer before installing the sealer. The sealant is moisture activated, so the system must be exceptionally clean and dry to get a good result.

Also used another brand, a one-part kit. Cheaped out and didn't change the dryer that time. In this case the results were not so good. It seemed to seal the leaks, but after a few months enough of the sealant had activated in the dryer to more or less plug it.

Eventually I got frustrated and replaced every componenent of the 15 year old a/c system. Now that was a permanent fix!

- JimY