I have a Sears 42 " mower 15.5 HP and need a diagram for Deck belt and drive belt. I've completed the task on first attempt, but when I start the engine with all controls in neutral the mower deck engages and the blades begin turning. Were may have I gone wrong when installing the belts. I Think I need a clear large print diagram. or could it be a minor adjustment needed.

Thanks for your assistance and knowledge