Unfortunately the system must be discharged before replacing the seal. Yep, those shields were used on the higher line cars to catch the oil.
Please read jamyers post above and take it to heart if you want to properly repair the ac on your Buick! When it comes to your AC system, there are usually no money saving shortcuts. It's a precision system and cutting corners often results in disappointment or failure. I've seen folks spend large amounts of money restoring a classic car with no questions asked, only to balk at a few hundred to restore the AC. They've spent 10-15K or more on the car,but choke at $3-500 to correctly repair the AC (if even near that much)?? I'm always puzzled by that.o No:
Thanks for the kind words! I learned about not scrimping-out on a/c the hard way. In the long run, it's cheaper and easier to do it right the first time. Heck, I just went halfsies with my bro-in-law on a MasterCool vacuum pump that'll pull down to something silly like 50 microns (better than 29.9 inches of mercury vacuum) for $120 delivered, that piece of equipment will pay for itself the next time I use it. And I'll add that anybody reading these words can do a better job than about 90% of the a/c shops out there - it ain't rocket science, but you gotta care about what you're doing and want to do it right. :beer
