E 150 1/2 Ton Van V6-4.2L VIN 2 (1997)
Fan Clutch: Testing and Inspection
Maximum Speed Fan Clutch Requirement Test
1. Perform Steps 1 through 5 of the Minimum Speed Fan Clutch Requirement Test. See: Minimum Speed Fan Clutch Requirement Test
2. Block off areas on each side of the radiator in the engine compartment and the front of the radiator grille. This will raise the temperature of the air
striking the fan clutch and should cause the fan to operate at maximum speed.
NOTE: The temperature of the air striking the fan clutch must be above 96° C (205° F) for maximum fan speed.
3. Place the climate control function selector switch in the MAX A/C position and the blower motor switch in the HI position.
4. Adjust the strobe to 3000 rpm.
5. Start the engine and adjust the engine speed until the strobe light flash and the water pump pulley mark are synchronized.
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.
6. Aim the strobe light at the fan blade retaining bolts. Adjust the strobe light until the light flash is synchronized with the marked fan blade retaining
bolt (fan blade appears to stand still).
7. If the fan blade speed is less than 2300 rpm, replace the fan clutch.
