Fan Clutch Test-Minimum Speed Requirement

Fan Clutch Test-Minimum Speed Requirement
1. Use a suitable marker to mark the water pump pulley, one of the fan blade retaining bolts and the crankshaft pulley.
2. Connect a tachometer to the engine.
3. Install a throttle adjusting tool.
4. Connect the Digital Photoelectric Tachometer.

5. 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.

Start the engine and run it at approximately 1,500 rpm until the normal operating temperature has been achieved.
6. Adjust the engine speed to 2,300 rpm.
7. Operate the strobe light at 3,000 rpm and aim it at the coolant pump pulley. Adjust the engine speed until the light flash and the coolant pump pulley mark are synchronized.
8. Aim the strobe light at the fan blade bolts. Adjust the strobe light until the light flash is synchronized with the marked fan blade bolt (the fan blade appears to stand still).
9. The fan blade speed must not be greater than 1,500 rpm at 3,000 coolant pump rpm.
10. Turn the engine off.
11. If the fan blade speed was greater than 1,500 rpm, install a new fan clutch.