1. Start by routing the belt around the crankshaft pulley.
2. Next, route the belt around the idler pulley.
3. Then, route the belt around the alternator pulley.
4. Next, route the belt around the water pump pulley.
5. Finally, route the belt around the power steering pump pulley.
Once the belt is routed correctly, you can tension it by using the tensioner bolt. The tensioner bolt is located on the idler pulley. To tension the belt, simply turn the tensioner bolt clockwise until the belt is snug.
Here is a diagram of the serpentine belt routing for a John Deere 490E excavator:
[Image of serpentine belt routing for John Deere 490E excavator]