CDL Air Brakes TestInspecting Air Brake SystemsEasy
A driver is performing a pre-trip inspection and notices that the air compressor drive belt is cracked and frayed. The air pressure gauge is showing a healthy 120 psi. What is the most appropriate action for the driver to take?
- AReplace the drive belt immediately before operating the vehicle.
- BAdd more air pressure to the system to compensate for potential compressor failure.
- CProceed with the trip, but monitor the air pressure closely.
- DReduce vehicle speed and avoid heavy braking to conserve air.
Show answer & explanationAnswer & explanation
Correct answer: A. Replace the drive belt immediately before operating the vehicle.
A cracked and frayed air compressor drive belt is a critical defect. While the system currently has adequate pressure, the belt could fail at any time, leading to a complete loss of air pressure and brakes. It must be replaced before operating the vehicle.
Why the other options are wrong
- B. Adding more air pressure is not possible without a functioning compressor and does not address the underlying problem.
- C. Operating with a damaged belt is unsafe, as it could fail at any moment.
- D. This is a temporary measure for a failing system, not a solution for a pre-trip defect.
Air Compressor Drive Belt Inspection
Inspection of the belt that drives the air compressor for signs of wear, damage, or improper tension.
- Belt drives the air compressor, essential for air pressure.
- Check for cracks, frays, glazing, or missing chunks.
- Check for proper tension (typically 1/2 to 3/4 inch play).
- A damaged belt must be replaced to prevent total air system failure.
Memory trick: Belt's health, system's wealth; a fray means danger, a quick death.