The majoriy of work on CAF tools requires standard tools. The only recommended tool for the mechanics tool box is the Kriket gauge, and it is only needed for CAF systems that utilize Poly-V belts for running the compressor.
The Krikit gauge is utilized for a symple and quick way to measure the belt tension for optimal belt drive performance.
The recommended belt tension of course, may vary by manufacturer. So, use the tool to follow the manufacturers instructions.
