The blades are always egaged. Has 3 pulleys and 1 belt. Don't see any springs. Manual engage handle. How do I fix this?

Does the blades engege when you lower the .

When you turn the key in neutral the blades are engaged. They are always on when the engine is running. Can't shut them off - only by shutting down the engine. The stop slot does not work to shut the blades off.

For a more detailed answer we will need the model number of the tractor?