1. Product Overview
The Gates B139 V-Belt is engineered for reliable power transmission in various industrial and automotive applications. Its composite, multi-purpose construction is designed to resist oil, heat, ozone, sunlight, weather, and aging, ensuring durability and consistent performance. This belt is suitable for all industrial applications, including V-flat drives.

Image 1.1: The Gates B139 V-Belt. This image displays the overall appearance of the V-belt, highlighting its black, ribbed exterior and typical V-shape.
2. Specifications
- Brand: Gates
- Model: B139
- Item Weight: Approximately 1.56 pounds (0.71 kg)
- Material: Composite construction designed to resist ozone, oil, heat, sunlight, and aging.
- Belt Style: V Belt
- Compatible Devices: Car (and various industrial applications)
- Package Dimensions: 16.87 inches (L) x 6.62 inches (W) x 1.46 inches (H)
- Included Components: One (1) Gates B139 Hi-Power II Belt

Image 2.1: Diagram illustrating the internal structure of a V-belt. This graphic shows the various layers and cords within the belt that contribute to its strength and flexibility.
3. Setup and Installation
Proper installation is crucial for the longevity and performance of your V-belt. Always refer to your equipment's service manual for specific installation procedures and safety guidelines. The following are general steps:
- Safety First: Ensure the equipment is turned off, de-energized, and locked out to prevent accidental startup.
- Remove Old Belt: Loosen the tensioning mechanism (e.g., idler pulley, motor mount bolts) and carefully remove the old belt from the pulleys.
- Inspect Pulleys: Check pulleys for wear, damage, or misalignment. Worn or damaged pulleys can significantly reduce belt life. Clean any debris from the pulley grooves.
- Install New Belt: Place the new Gates B139 V-Belt onto the pulleys without forcing or prying. Forcing the belt can damage its internal cords.
- Tensioning: Adjust the tensioning mechanism according to the equipment manufacturer's specifications. Correct tension is vital; too loose can cause slipping, and too tight can lead to premature wear on both the belt and bearings.
- Alignment: Verify that the pulleys are properly aligned. Misalignment causes uneven wear and reduces belt efficiency.
- Run-in Period: After installation, run the equipment for a short period (e.g., 30 minutes) and then recheck the belt tension. Belts can stretch slightly during initial operation.

Image 3.1: Close-up view of the Gates B139 V-Belt's cross-section. This image details the layered construction and the V-shape designed for optimal grip in pulley grooves.
4. Operating Principles
The Gates B139 V-Belt transmits power by wedging into the grooves of a V-pulley. This wedging action increases the effective coefficient of friction, allowing for efficient power transfer with less tension than flat belts. The belt's design ensures a firm grip, preventing slippage under normal operating loads. It is designed to operate within specific temperature ranges and load capacities as determined by the equipment manufacturer.
5. Maintenance
Regular maintenance extends the life of your V-belt and ensures optimal equipment performance.
- Routine Inspection: Periodically inspect the belt for signs of wear, cracking, fraying, glazing, or hardening. Check for any foreign objects lodged in the grooves.
- Tension Check: Verify belt tension regularly. Adjust as necessary to maintain the manufacturer's recommended tension.
- Cleanliness: Keep the belt and pulleys free from oil, grease, dirt, and other contaminants, which can cause slippage and premature wear.
- Temperature: Ensure the operating environment does not exceed the belt's recommended temperature limits. Excessive heat can degrade belt materials.
- Storage: Store spare belts in a cool, dry place away from direct sunlight and ozone-generating equipment.
6. Troubleshooting
Common issues with V-belts and their potential solutions:
| Symptom | Possible Cause | Solution |
|---|---|---|
| Belt Squealing/Slipping | Insufficient tension, glazed belt, oil/grease on belt/pulleys, worn pulleys | Adjust tension, clean belt/pulleys, replace worn belt/pulleys |
| Premature Belt Wear | Incorrect tension (too high or too low), pulley misalignment, worn pulleys, excessive heat, incorrect belt type | Adjust tension, align pulleys, replace worn components, ensure proper belt selection |
| Belt Fraying/Cracking | Aging, exposure to chemicals/oil, excessive heat, improper storage, small pulley diameter | Replace belt, protect from contaminants, ensure proper pulley size |
| Vibration | Worn belt, pulley imbalance, misalignment | Replace belt, balance pulleys, align pulleys |
7. Product Support and Part Identification
For assistance with identifying the correct Gates parts or finding a local distributor, Gates offers the NaviGates online and app-based catalog. This tool allows you to search for parts by vehicle market, competitor part number, or by scanning a VIN number.
Video 7.1: Introducing NaviGates - An Online and App Based Catalog. This video demonstrates how to use the Gates NaviGates application to efficiently search for and identify Gates belts, hoses, and other product solutions, as well as locate nearby auto parts stores.
For further support, please visit the official Gates website or contact their customer service.
8. Warranty Information
Specific warranty details for the Gates B139 V-Belt are typically provided at the point of purchase or can be found on the official Gates website. It is recommended to retain your proof of purchase for any warranty claims. For detailed warranty terms and conditions, please consult the manufacturer's official documentation or contact Gates customer support directly.