Toyota Repair: air conditioning, toyota celica, sight glass

Question
1991 Toyota Celica needs the AC recharged. Several yrs ago it was converted to use R34 freon. My question: Can I recharge it myself? Any problems I should expect or look out for?

Many thx, in advance.  Jack

Answer
You can get the R134 recharge kit at most autoparts stores, if the system is completely out of freon it will take about one and a half pounds of freon. If there is still some freon in it and you just want to add hook up the can to the valve and add just enough to eliminate bubbles in the sight glass with the emgine running and the a/c on, the sight glass should be located on top of the receiver drier near the radiator on the a/c condenser.