Overfilled freon system??? Not room for the liquid freon to turn into a gas, so it goes over pressure and it kicks out.
Look up your system's R-12 freon capacity.
Evacuate the whole system clean and empty, this allows the vacuum pressure to boil out any remaining moisture in the system and then evacuates it out.
Then reinstall the proper amount of 134 Freon (from the R-12 specs) without over filling it.
Put a meat thermometer in the AC duct work as you are filling the system back up to keep and eye on the temperature dropping, as the engine is running and AC on Full Cool. Filling the system from the low pressure side only. When you get it down to 60° (f) you are getting close and your system should be fully working.
Keep adding 134 freon until the duct temp gets to 55 - 50° then the system will be full. Should be close to the same amount of freon in the specs.
Happy Motoring
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