A/c issues - questions..

[JITB]

Alright..soo my A/c compressor in the 929 i "thought" wasnt working. but i was told that i needed to jump it, because it didnt have any freon in it from the previous owner. So i doo that, and its spinning! i get freon, charge it up.. with a small can..it doesnt get cool. So i go get a big can, and crank it start to fill it, it gets ice cold, and starts to make a loud clicking noise from the compressor(lke a baseball card in a bicycle spoke).. but it stops when i rev the motor. So i empty the can... and after about 20 minutes.. i stop filling, and notice its not as cold as it was.. its just cool air..

Do i need more freon?

What was that clicking noise?