03 rancher 350fm wont charge battery

Hello, im new here mostly because ive been able to handle my own problems. I just bought a 350 rancher from a friend and the bike didnt charge. Knowing what i know i pulled the voltage regulator off and it was shot! The slot the red wire goes in was broken off so i thought well thats my problem. That didnt fix anything. i can ohm out the yellow wires from the stator and they come back good. Have good ground from green wire. The red wire in the plug looks like it may not be making contact! If i jump the bike off or charge the battery the bike runs fine but still no charge. HELP!!