Fan Clutch Test - Minimum Speed Requirement
WARNING: This page is about a different car, the 2006 Mercury Grand Marquis and 2006 Ford Crown Victoria. However, it is still accessible from the selected car via links, so may be relevant.
- Use a suitable marker to mark the coolant pump or fan pulley and one of the fan blades.
- Make sure the A/C is OFF, if equipped.
- Start the engine and run it at approximately 2,000 rpm for 5 minutes or until there is a noticeable reduction in fan noise to allow the fan clutch to go into disengaged mode.
- Aim a laser photo tachometer at the coolant pump or fan pulley. Run the engine to achieve 3,000 rpm at the coolant pump or fan pulley.
- With the coolant pump or fan pulley at 3,000 rpm, aim the laser photo tachometer at the fan blade. Monitor and record fan speed.
- The fan blade speed must be less than the specified rpm at 3,000 rpm coolant pump or fan pulley rpm.
- Turn the engine off.
- If the fan blade speed was greater than specified, install a new fan clutch.
WARNING:
To avoid the possibility of personal injury or damage to the vehicle, do not operate the engine until the fan blade has been first examined for possible cracks and separation. Failure to follow these instructions may result in serious personal injury.