If you make a list of the most frequently replaced components in a modern vehicle, serpentine belts will certainly be near the top. Compared to the lifespan of V-belts in older vehicles, these last longer but eventually wear out. If you enjoy fixing things in your garage, it will be useful to know how to change a serpentine belt.
When should a serpentine belt be replaced?
There is no recommended replacement interval for a serpentine belt. The general rule is to inspect it at every oil change, which is every 30,000 to 50,000 miles or once a year. Replacement is only required when the belt’s condition is poor.
Additionally, you can replace the belt during cooling system maintenance. In some engines, the belt also operates the radiator fan, water pump, heater core, and compressor. You should change it when replacing or repairing any of these components.
There are a few signs to watch for with a bad serpentine belt. The symptoms are mostly noises coming from various components. The belt will slip and create noise when the V-ribs on its underside wear out.
Pulley misalignment is another reason for noise. Several types of pulleys, including an automatic belt tensioner pulley, an idler pulley, a power steering pump pulley, and a water pump pulley, can create belt noise. A loose or worn harmonic balancer can also create a similar sound.
Worn bearings in idler pulleys can also create such noises. In this case, you must replace the pulleys as it is not possible to lubricate the bearings or reseal them.
How to change a serpentine belt?
The serpentine belt runs through all engine-driven accessories, including the water pump, power steering pump, air conditioning compressor, and alternator. The long belt simplifies the operation of all pumps and pulleys under the hood.
You will need these tools and follow the steps to replace it.
1. Tools for replacement
- A serpentine belt
- Basic hand tools
- Removal tools
- Rags
2. How to change a serpentine belt: the steps
- Check the belt routing diagram before starting the process. If you can’t find the owner’s manual, get the diagram online. Carefully observe how the old belt wraps around the pulleys.
- Place the wrench or a removal tool with enough space to move on the tensioner before releasing it. Carefully release the self-adjusting belt tensioner.
- Remove the old serpentine belt. You should also check the tensioner pulley at this time for any signs of wear. You will need to replace it if it is damaged or has extremely tight or loose connections.
- Check all the pumps and pulleys for the water pump, AC compressor, smog pump, and alternator. Don’t forget to inspect the idler pulleys as well. Make sure each of them moves freely without being loose or tight.
- Place the new belt in its path. Ensure the belt’s ribs fit into the pulley grooves.
Tighten the tensioner. That’s how to change a serpentine belt.