Radiator Cooling Fan — Liberty Service Manual

Labor

Replace — Fan Module0.6 hr

Warranty 0.0 hrSkill B

Procedures

Electric Radiator Fan - Installation9 steps

Install cooling fan to shroud. Tighten fan shroud to radiator bolts to 9 Nm (80 in. lbs.).
Install fan shroud assembly into the vehicle.
Install fan shroud to radiator mounting bolts (1). Tighten bolts to 9 Nm (80 in. lbs.).
Connect fan motor wire connector (2) to harness connector and attach connector to shroud.
Install the radiator hose retainer (3) to the electric fan shroud.
Install the transmission cooling line retainer bolt (2) to the electric fan shroud.
Install the combination coolant recovery/washer fluid bottle.Coolant Recovery Bottle - Installation
Connect battery negative cable.
Start engine and check fan operation.

Electric Radiator Fan - Removal7 steps

Disconnect battery negative cable.
Remove combination coolant recovery/washer fluid bottle.Coolant Recovery Bottle - Removal
Disengage the radiator hose retainer (3) from the electric fan shroud.
Remove transmission cooling line retainer bolt (2) from the electric fan shroud.
Disconnect the electric fan connector (2) from the electric fan shroud.
Remove two bolts (1) and lift the electric fan shroud from vehicle.
Remove cooling fan from shroud.

Electric Radiator Fan - Descriptionreference

DESCRIPTION The fan (4) is electrically controlled by the Powertrain Control Module (PCM) through the fan control relays. The relays are located in the Power Distribution Center (PDC) in the engine compartment.

Factory service manual

From the 2008 KK factory manual — descriptions, specs, torque & procedures for this part.

RADIATOR-ELECTRIC.

TEMPERATURE GAUGE READS	1. Trailer is being towed, a	1. This may be a temporary
HIGH OR THE COOLANT	steep hill is being climbed,	condition and repair is not
WARNING LAMP ILLUMINATES. vehicle is operated in slow	necessary. Turn off the air
COOLANT MAY OR MAY NOT BE moving traffic, or engine is	conditioning and attempt to
LOST OR LEAKING FROM THE	being idled with very high	drive the vehicle without any of
COOLING SYSTEM.	ambient (outside) temperatures the previous conditions.

and the air conditioning is on. Observe the temperature gauge.

                          Higher altitudes could             The gauge should return to the
                          aggravate these conditions.        normal range. If the gauge does

not return to the normal range, determine the cause for overheating and repair.

                          2. Is the temperature gauge        2. Check gauge. (Refer to
                          reading correctly?                 INSTRUMENT CLUSTER -

FAN-RADIATOR-ELECTRIC📷 5

Description

1 - RADIATOR 2 - ELECTRIC COOLING FAN CONNECTOR 3 - FAN SHROUD 4 - 2 SPEED ELECTRIC COOLING FAN

The fan (4) is electrically controlled by the Powertrain Control Module (PCM) through the fan control relays. The relays are located in the PDC in the engine compartment.

Operation

The electric radiator cooling fan is controlled by the Powertrain Control Module (PCM) through the radiator cooling fan relays. The PCM regulates fan operation based on input from the engine coolant temperature sensor, battery temperature sensor, air conditioning select switch and vehicle speed.

The fan is not energized during engine cranking regardless of the electrical input from the temperature sensors and air conditioning switch. However, if engine operation conditions warrant fan engagement, the fan will run once engine starts.

On vehicles NOT equipped with AC: The relay is energized when the coolant temperature is above 80° C (176° F), or battery temperature sensor above -12° C (10° F). It will then de-energize when coolant temperature drops below 82° C (180° F), or battery temperature sensor below -9° C (16° F).

Vehicles Equipped with AC: In addition to using coolant temperature and battery temperature sensor to control cooling fan operation, the cooling fan will also be engaged when the, air conditioning system is activated. The relay is also energized when air conditioning is selected and coolant temperature is above 95° C (203° F), or, air conditioning is selected and battery temperature sensor is above 41° C (106° F). It will then de- energize when air conditioning is selected and coolant temperature is below 92° C (198° F), or air conditioning is selected and battery temperature is below 38° C (100° F).

Removal

1 - SPECIAL TOOL 6958 SPANNER WRENCH WITH ADAPTER PINS 8346 2 - FAN

If the fan blade is bent, warped, cracked or damaged in any way, it must be replaced only with a replacement fan blade. Do not attempt to repair a damaged fan blade.

NOTE: For 3.7L Heavy Duty/Max Cool/Trailer Tow cooling package, the viscous fan cannot be removed separate from the shroud. Both fan and shroud must be removed together.

Disconnect battery negative cable.

Using special tool 6958 spanner wrench and 8346 adapters, remove the viscous fan from the water pump.

See Fig. 52. 1 - RADIATOR 2 - ELECTRIC COOLING FAN CONNECTOR 3 - FAN SHROUD 4 - 2 SPEED ELECTRIC COOLING FAN

Gently lay fan into shroud.

Disconnect the electrical connector (2) for the electric fan, then disconnect connector from shroud.

Remove the two fan shroud mounting bolts connecting the fan shroud to the radiator. See Fig. 53.

Remove the shroud and fan from the vehicle.

Installation

1 - RADIATOR 2 - ELECTRIC COOLING FAN CONNECTOR 3 - FAN SHROUD 4 - 2 SPEED ELECTRIC COOLING FAN

Install fan shroud assembly into the vehicle. Tighten fan shroud to radiator bolts to (5.5 N.m (50 in. lbs.).

Install shroud mounting bolts tighten bolts to 10 N.m (89 in. lbs.).

Connect fan motor wire connector to harness connector, and attach connector to shroud.

Connect battery negative cable.

Start engine and check fan operation.

FAN-VISCOUS RADIATOR📷 1

Description

1 - VISCOUS FAN DRIVE 2 - THERMOSTATIC SPRING 3 - MOUNTING NUT TO WATER PUMP HUB

CAUTION: If the viscous fan drive is replaced because of mechanical damage, the cooling fan blades should also be inspected. Inspect for fatigue cracks, loose blades, or loose rivets that could have resulted from excessive vibration. Replace fan blade assembly if any of these conditions are found. Also inspect water pump bearing and shaft assembly for any related damage due to a viscous fan drive malfunction.

The thermal viscous fan drive (1) is a silicone-fluid-filled coupling used to connect the fan blades to the water pump shaft. The coupling allows the fan to be driven in a normal manner. This is done at low engine speeds while limiting the top speed of the fan to a predetermined maximum level at higher engine speeds. See Fig. 55.

Operation

A thermostatic bimetallic spring coil is located on the front face of the viscous fan drive unit. This spring coil reacts to the temperature of the radiator discharge air. It engages the viscous fan drive for higher fan speed if the air temperature from the radiator rises above a certain point. Until additional engine cooling is necessary, the fan will remain at a reduced RPM regardless of engine speed. Normally less than 800 RPM.

Only when sufficient heat is present, will the viscous fan drive engage. This is when the air flowing through the radiator core causes a reaction to the bimetallic coil. It then increases fan speed to provide the necessary additional engine cooling.

Once the engine has cooled, the radiator discharge temperature will drop. The bimetallic coil again reacts and the fan speed is reduced to the previous disengaged speed.

VISCOUS RADIATOR FAN

If the fan assembly free-wheels without drag (the fan blades will revolve more than five turns when spun by hand), replace the fan drive. This spin test must be performed when the engine is cool.

For the following test, the cooling system must be in good condition. It also will ensure against excessively high coolant temperature.

WARNING: Be sure that there is adequate fan blade clearance before drilling.

1. Drill a 3.18-mm (1/8-in) diameter hole in the top center of the fan shroud. 2. Obtain a dial thermometer with an 8 inch stem (or equivalent). It should have a range of -18° to 105°C (0°

to 220° F). Insert thermometer through the hole in the shroud. Be sure that there is adequate clearance from the fan blades. 3. Connect a tachometer and an engine ignition timing light (timing light is to be used as a strobe light). 4. Block the air flow through the radiator. Secure a sheet of plastic in front of the radiator (or air conditioner condenser). Use tape at the top to secure the plastic and be sure that the air flow is blocked. 5. Be sure that the air conditioner (if equipped) is turned off.

WARNING: Use extreme caution when the engine is operating. Do not stand in a direct line with the fan. Do not put your hands near the pulleys, belts or fan. Do not wear loose clothing.

6. Start the engine and operate at 2400 RPM. Within ten minutes the air temperature (indicated on the dial thermometer) should be up to 93° C (200° F). Fan drive engagement should have started to occur at between 91° to 96° C (195° to 205° F). Engagement is distinguishable by a definite increase in fan flow noise (roaring). The timing light also will indicate an increase in the speed of the fan. 7. When the air temperature reaches 93° C (200° F), remove the plastic sheet. Fan drive disengagement should have started to occur at between 62° to 85° C (145° to 185° F). A definite decrease of fan flow noise (roaring) should be noticed. If not, replace the defective viscous fan drive unit.

REMOVAL-2.8L DIESEL📷 1

1 - SPECIAL TOOL 6958 SPANNER WRENCH 2 - FAN

1. Disconnect negative battery cable.

NOTE: The thermal viscous fan drive/fan blade assembly is attached (threaded) to fan support.

2. Remove fan blade/viscous fan drive assembly from water pump using special tool 6958 spanner wrench, by turning mounting nut counterclockwise as viewed from front. Threads on viscous fan drive are

RIGHT HAND. 1 - COOLING FAN AND FAN DRIVE VISCOUS

CLUTCH ASSEMBLY📷 2

2 - FAN SUPPORT

3. Do not attempt to remove fan/fan drive viscous clutch assembly (1) from vehicle at this time. 4. Do not unbolt fan blade assembly from fan drive viscous clutch at this time.

1 - IDLER PULLEY 2 - COOLING FAN SUPPORT 3 - RETAINING BOLTS 4 - ENGINE LIFT HOOK

5. Remove fan shroud to radiator bolts. 6. Remove fan shroud and fan blade/fan drive viscous clutch assembly as a complete unit from vehicle. 7. After removing fan blade/fan drive viscous clutch assembly, do not place viscous clutch in horizontal position. If stored horizontally, silicone fluid in the fan drive viscous clutch could drain into its bearing assembly and contaminate lubricant. 8. Remove four bolts securing fan blade assembly to fan drive viscous clutch. 9. Remove cooling fan support (2) from engine block.

REMOVAL-3.7L/4.0L📷 1

1. Partially drain the cooling system. See STANDARD PROCEDURE. 2. Remove the upper radiator hose. 3. Remove the air filter housing assembly. Refer to REMOVAL .

From Water Pump

4. Using Tool 6958 and adapter pins 8346 (1), remove fan/viscous fan drive assembly from water pump. Do not attempt to remove fan/viscous fan drive assembly from vehicle at this time. 5. Position the fan/fan drive assembly in the radiator shroud. 6. Remove the two shroud mounting screws. 7. Remove the radiator shroud and fan drive assembly. 8. After removing fan blade/viscous fan drive assembly, do not place viscous fan drive in horizontal position. If stored horizontally, silicone fluid in the viscous fan drive could drain into its bearing assembly and contaminate lubricant. 9. Remove four bolts securing fan blade assembly to 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 (.090 inch). Rocking motion of opposite blades should not exceed 2.0 mm (.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-2.8L DIESEL📷 1

1 - COOLING FAN AND FAN DRIVE VISCOUS CLUTCH ASSEMBLY 2 - FAN SUPPORT

1. Assemble fan blade to viscous fan drive. Tighten mounting bolts to 23.7 N.m (210 in. lbs.) torque.

NOTE: The viscous fan and fan shroud must be installed as an assembly.

2. Gently lay fan and viscous drive into fan shroud.

1 - SPECIAL TOOL 6958 SPANNER WRENCH 2 - FAN

3. Install the fan shroud to radiator mounting bolt. Tighten bolts to 9 N.m (80 in. lbs.) torque. 4. Thread the fan and viscous drive onto the fan support and tighten nut using special tool 6958 spanner wrench. 5. Install cooling fan support to engine block. Torque bolts to 149 N.m.(110 ft. lbs.). 6. Connect negative battery cable.

INSTALLATION-3.7L/4.0L📷 1

1. Install fan blade assembly to viscous fan drive. Tighten bolts to 23 N.m (17 ft. lbs.) torque. 2. Position fan blade/viscous fan drive assembly into the radiator shroud. 3. Install the radiator shroud and fan drive assembly into the vehicle. 4. Install fan shroud retaining screws. Tighten screws to 6 N.M (50 lbs. in.) 5. Using Tool 6958, install the fan blade/viscous fan drive assembly to the water pump shaft. Tighten mounting nut to 50 N.m (37 ft. lbs.). 6. Install the upper radiator hose. 7. Fill cooling system. See STANDARD PROCEDURE. 8. Connect battery negative cable.

THERMOSTAT-ENGINE COOLANT