Mower deck question

I have a Yard King 22HP, 52" deck tractor. It's about 20 years old.

This year I seem to have an issue trying to mow with it...it's has an awful noise. Spindles have been greased and were replaced last year. The best I can determine (and I'm open for correction) is the brake on the deck, left side, is always rubbing on the pulley and is the source of the noise. If I manually swing the brake off the pulley, as soon as I engage the belt, the belt pulley is made to swing over and push the brake onto the spindle pulley.

Help?