Expansion Valve replacement

[outlaw420]

I have a 1993 MX-6 with the V-6.

What happened to the A/C is i had just retuned home from about a 40 mile trip when the engine was turned off something blew and emptied the freon from the system. I was told by the people that owned it before that it happened to them(about 7 years ago) and all they had to replace was the expasion valve. I have looked all over the lines and have found no damage that a visiual inspection can indicate. I have yet to tear into the dash to look at the condensor yet(next on my list) but i was wondering if this sort of thing has happened to anyone else and can give advise

Thanks
Rob