When i shift tractor into gear it takes off and won't stop. When i engage the clutch/brake it continues to drive. I have to turn it off to stop it. When it's turned off i can shift thru the gears smoothly. but when i start it and put it in gear it will not go back out of gear. I noticed that the clutch/brake has very little pull untill the last several inches. It didn't do this before. I've checked the springs, brake pad, pulley's etc. This all happened after my drive belt came off. I replaced it and this started happening. It's been two wks. and i could sure use some help. Thanks