What a fun car to drive, but sure needs a lot of love and personal attention.

Here goes. Bought this car a few months ago. AC blew hot air. Hooked up gauges and determined it had no pressure and was empty. Took it to mechanic, who recharged refrigerant. Worked great and blew cold. Two days later, blowing hot air again. Took it back to mechanic. About 60% of freon leaked out in the two days.

After two days with my car and looking for leaks, they think the evaporator needs replacing (at a total cost of $787). I feel like they are guessing at this solution because they haven't found any other obvious leaks. My questions:

1. Is there an absolute way to find the leak (to confirm whether or not the evaporator really needs replacing?
2. If it is the evaporator, can I save the labor cost and replace it myself (I've heard this is not an easy job)?
2. any other ideas or approaches I can take?

 

There are different ways to find refrigerant leaks. One involves an electronic "sniffer" that senses the presence of the refrigerant. You have to get it right up close to the leak and it gives you a beep. Another is by using a dye that shows under "black light". The problem is, that neither method is great for finding a leak in the evaporator core, which is buried under the dash in the plenum. You can't see in there to use the "black light" nor can you get the sniffer in there to find it that way. Generally, what they do is check the whole system under the hood as carefully as possible to see if the leak can be found there. If not, by process of elimination, you are left to conclude that the leak must be at the evaporator core.
To get the evaporator core out, you basically have to remove the entire dashboard. It's a big job. If you are considering doing it youself, first get a shop manual or at least a Chilton's or Haynes manual and study the chapter on removing the dashboard. Then you can decide whether your skills and your toolbox are up to the task.
There are "stop leak" systems out there for A/C systems, but I'd be a little leery of them as they could plug up something in the system that you don't want plugged up.
Alternatively, put the top down and enjoy the warm weather.

 

Using the blacklight dye..once the system is empty(After it leaks out), Using the Nozzle on a "SPORTS-BOTTLE" (or the "POPTOP" on a bottle of spring water).Squirt the entire contents into the center dash vent. Use a blacklight to watch for the dye traces at the condensation drain.