Heavy Duty Belt and Tensioner Installation for Cummins Engines
Initial Safety Precautions
Before beginning any work on the engine, ensure the following safety steps:
- Set the parking brake.
- Remove the keys from the ignition.
- Disconnect the vehicle's battery.
Using high-quality replacements like the Cummins engine belt can ensure durability and optimal performance.
Inspecting the Tensioner and Serpentine Belt
The tensioner and serpentine belt should be inspected for signs of wear. Common issues include:
| Issue | Significance |
|---|---|
| Noise | Indicates potential bushing wear or tension loss. |
| Improper Belt Tracking | Shows misalignment or worn bushings. |
| Cracks or Abrasion | Requires immediate belt replacement. |
To test for noise, lightly spray water on the ribbed side of the belt while the engine is running. If the noise changes or temporarily disappears, this indicates either low belt tension or misalignment.
Removing the Old Belt
Follow these steps to remove the serpentine belt:
- Relieve tension on the belt using a ½-inch ratchet.
- Slide the belt off the pulleys, starting with the fan and alternator AC belts.
- Inspect the belt using a wear gauge, checking for rib profile, rib depth, and cracks.
Belt dressing should not be used on EPDM belts as it can cause contamination and ruin the material.
Inspecting and Replacing the Tensioner
To remove the tensioner:
- Use a 13mm socket to unbolt the tensioner.
- Inspect for signs of wear, such as bearing noise or metal-to-metal contact between the arm and spring case.
- Replace the tensioner if it has cracks, broken arms, or spring cases.
For alignment checks, a laser alignment tool can be used to ensure the pulleys are properly aligned.
Installing the New Belt and Tensioner
Before installing the new components:
- Clean the tensioner mounting surfaces with light abrasive sandpaper.
- Ensure the mounting surface is free of oxidation or foreign materials to prevent misalignment.
Install the new tensioner and belt as follows:
- Position the tensioner into the mounting holes and tighten the bolts with a 13mm socket to 35 ft-lb using a torque wrench.
- Install the serpentine belts and release the tensioner to apply pressure to the belt.
- Reconnect the battery and start the engine.
Final Checks
Verify that all belt ribs are aligned properly within the pulley grooves. Misalignment can lead to premature belt failure. Run the engine for a few minutes to ensure the belt operates smoothly.
For expert support and genuine parts, consult a trusted cummins dealer.