Hello everyone. First post here and hopefully everything goes well. I will try to describe exactly whats happening so please read entire post.

82 300D is the car. As stated I have a weird noise coming from the alternator. Now before you tell me its the pulley or the alternator, they're both brand new. Also, my previous pulley and alternator were doing the exact same thing! So I know its not the pulley or alternator being bad. The sound is basically like a squealing belt. Well i replaced the belt twice. I even loosened the belt so loose that im worried it could fly off. I have tried every tension from too tight to too loose to make sure its not the belt. Also, the alternator isnt charging at all. I only have 12.0v at the battery with a brand new alternator. Now here's the weird part. While the car is running and the alternator is making the sound, I can disconnect the battery and the sound stops!! Thats whats throwing me for a loop. I have cleaned every connection, replaced parts, put in a new battery, and still no luck. Please if anyone has come across this issue let me know. Also if someone can point me in the right direction to look for an issue please do. Thanks for any help you can provide