Fan Blade: Service and Repair
RADIATOR FANREMOVAL
NOTE: Fan belt removal is not necessary to remove cooling system fan.
1. Disconnect the negative battery cable at battery.
2. Remove the plastic air cleaner intake tube.
3. Remove two-piece fan shroud. Remove lower half first.
4. The thermal viscous fan drive/fan blade assembly is attached (threaded) to the water pump hub shaft. Remove the fan blade/fan drive assembly from water pump by turning the mounting nut counterclockwise (as viewed from front). Threads on the viscous fan drive are RIGHT HAND. A Snap-On 36 MM Fan Wrench (number SP346 from Snap-On Cummins Diesel Tool Set number 2017DSP) can be used with Special Tool 6958 Spanner Wrench and Adapter Pins 8346 to prevent the pulley from rotating. Do not unbolt fan blade assembly from the viscous fan drive at this time.
5. After removing fan blade/fan drive assembly do not place the thermal viscous fan drive in the horizontal position. If stored horizontally, the silicone fluid in the viscous fan drive could drain into its bearing assembly and contaminate the bearing lubricant.
6. Remove the four bolts securing the fan blade assembly to the viscous fan drive.
CLEANING
Clean the fan blades using a mild soap and water. Do not use an abrasive to clean the blades.
INSPECTION
WARNING: DO NOT ATTEMPT TO BEND OR STRAIGHTEN FAN BLADES IF FAN IS NOT WITHIN SPECIFICATIONS.
CAUTION: If fan blade assembly is replaced because of mechanical damage, water pump and viscous fan drive should also be inspected. These components could have been damaged due to excessive vibration.
1. Remove fan blade assembly from viscous fan drive unit (four bolts).
2. Lay fan on a flat surface with leading edge facing down. With tip of blade touching flat surface, replace fan if clearance between opposite blade and surface is greater than 2.0 mm (0.090 in.). Rocking motion of opposite blades should not exceed 2.0 mm (0.090 in.). Test all blades in this manner.
3. Inspect fan assembly for cracks, bends, loose rivets or broken welds. Replace fan if any damage is found.
INSTALLATION
1. Install fan blade assembly to viscous fan drive. Tighten bolts to 23 Nm (17 ft. lbs.) torque.
2. Install the fan blade/viscous fan drive assembly to water pump shaft.
3. Install fan shroud.
4. Install air cleaner intake tube.
5. Connect negative battery cable.