Radiator Cooling Fan: Service and Repair
FAN/RADIATORREMOVAL
5.7L ENGINES
1. Raise vehicle on hoist.
2. Drain cooling system.
NOTE: The hydraulic fan drive is driven by the power steering pump. When removing lines or hoses from fan drive assembly use a drain pan to catch any power steering fluid that may exit the fan drive or the lines and hoses.
NOTE: When ever the high pressure line fittings are removed from the hydraulic fan drive the O-rings must be replaced.
3. Disconnect two high pressure lines at hydraulic fan drive. Remove and discard o-rings from line fittings.
4. Disconnect low pressure return hose at hydraulic fan drive.
NOTE: The lower mounting bolts can only be accessed from under vehicle.
5. Remove two lower mounting bolts from the shroud.
6. Lower vehicle.
7. Disconnect the electrical connector for the fan control solenoid.
8. Disconnect the radiator upper hose at the radiator and position out of the way.
9. Disconnect the power steering gear outlet hose and fluid return hose at the cooler.
10. Remove two upper mounting bolts from the shroud.
11. Remove the shroud and fan drive from vehicle.
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 inch). Rocking motion of opposite blades should not exceed 2.0 mm (0.090 inch). 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
CAUTION: There is an external ground wire connected to the hydraulic fan drive located at the electrical connector on the fan assembly. This ground MUST remain connected at all times. Failure to ensure ground wire is connected when engine is operating can cause severe damage to the JTEC module.
1. Position fan drive and shroud in vehicle.
2. Install fan shroud upper mounting bolts. Do not tighten at this time.
3. Install radiator upper hose onto radiator.
4. Connect power steering cooler hoses.
5. Raise vehicle on hoist.
6. Install fan shroud lower mounting bolts. Tighten to 6 Nm (50 inch lbs.).
NOTE: When ever the high pressure line fittings are removed from the hydraulic fan drive the o-rings located on the fittings must be replaced.
7. Lubricate the o-rings on the fittings with power steering fluid then connect inlet and outlet high pressure lines to fan drive. Tighten inlet line to 49 Nm (36 ft. lbs.) tighten outlet line to 29 Nm (21 ft. lbs.).
8. Connect low pressure return hose to fan drive.
9. Lower vehicle.
10. Install radiator upper hose.
11. Connect electrical connector for hydraulic fan control solenoid.
12. Tighten fan shroud upper mounting bolts to 6 Nm (50 inch lbs.).
13. Refill cooling system.
CAUTION: Do not run engine with power steering fluid below the full mark in the reservoir. Severe damage to the hydraulic cooling fan or the engine can occur.
14. Refill power steering fluid reservoir and bleed air from steering system.
15. Run engine and check for leaks.