Small Engines (Lawn Mowers, etc.): toro lawn mower clutch/brake, toro wheel horse, gear components

Question
i have a toro wheel horse 12-38 xl model #71184 and the clutch/brake is not engaging. how does this work and what will remedy this problem. the belts are in good shape and tensioned properly but it either will not engage or it engages very little. i would appreciate your input. thanks

Answer
What exactly is it doing or not doing, is the mower able to move on it's own? Is someone able to help you to see if the rear transaxle pulley is turning? This will tell you if the belt is slipping or if the problem is with in the gear components of the transaxle. It takes very little with the great force of the engine to make a belt slip. If I'm right this model is around 13 years old, as the belt ever been changed? Sometimes the belt will look fine but be glazed over so it slips, even with fair tension on it. I would almost bet your ready for a change of drive belt....Tom