Yes, to avoid overcharging like I said just put about 1/3 of a can in there. I think a can is 12 oz. so that should be about 4 oz. That's a very small amount. Even if you were to slightly overcharge by a couple oz. it's not going to kill anything. If after 4 oz. you sense there is progress being made, you can proceed with adding a little more, maybe an ounce at a time. The key is to do so VERY slowly, maybe take an hour to do this whole process. And don't turn the can upside down - liquid refrigerant hitting the valves in the compressor will surely kill it. If things appear to be going too slowly, just put the can over the engine where heat will cause it to evaporate more rapidly from the can into the system.

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08 W251 R350
97 W210 E320
91 W124 300E
86 W126 560SEL
85 W126 380SE Silver
85 W126 380SE Cranberry
79 W123 250
78 W123 280E
75 W114 280