444se chain brake

[Phileroo]

So i got a old husky 444se from my cousin who got it from a guy who got it from a guy who picked it up off the curb. Anyway i worked out most of the problems and now i'm down to the chain brake. Plain and simple, it doesn't stop the chain. Now i didn't take a micrometer to the band and check the thickness but its in one piece. I got the spring tensioned up all the way that pulls on the band. It clicks back in forth and disengages fine. It just doesn't stop the chain when its running and i can get the chain running while the brake is still engaged.

Any ideas or help would be great. Thanks