E28 AC leak

[Aaron Lung <alung@xxxxxxxxx>]

Just wondering if any of you folks have any opinions regarding
AC leaks.

I have an 88 528e with 88K miles.  The AC was fine until
about 3 yrs ago when I had to recharge it with just less
than 1 pound of R12 freon to get it cold again.   Now,
it looks like I have to put in another can of stuff.

It's obvious I have a very, very slow leak somewhere, and obviously
nobody legally sells anything R12-based  over-the-counter. :-(

Some dumb questions:
- - Assuming I can find a can of  leak sealer and squirt it into the
  system,  would this suffice?
- - I assume I'll have to evacuate and recharge the system sooner or
   later since it'll be full of air sooner or later.  If I take the car 
into
   a shop, is leak sealant a legal thing they can add?
- - since I seem to lose about 1 lb of freon every 3yrs, what's the
   easiest way to locate and detect the leak?  I seem to remember
   hearing something about using a propane torch, but I'm not sure
   I want to holding a torch inside the engine block while the engine's
   running.
- - If I take it to the shop, what's the first thing they'd want to do?  
   Repair/replace gaskets?  I assume this won't be cheap.  Or is it
   OK to simply evacuate/recharge the system?  Though I thinkit's illegal
   now to simply recharge without fixing anything.  No?
- - I don't plan on replacing the system with an R34-equivalent.  I think
   I'd rather drive with the windows open or get a new car :-(

any insight or opinions would be great

thanks
aaron

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