Engine Cooling System - Removal & Installtion Dodge Pickup R1500

ETHYLENE-GLYCOL MIXTURES

The use of aluminum cylinder blocks, cylinder heads and water pumps requires special corrosion protection. Only Mopar® Antifreeze/Coolant, 5 year/100,000 Mile Formula (ethylene-glycol base coolant with corrosion inhibitors called HOAT, for Hybrid Additive Technology) is recommended. This coolant offers the best engine cooling without corrosion when mixed with 50% distilled water to obtain a freeze point of -37°C (-35°F).

The required ethylene-glycol (antifreeze) and water mixture depends upon the climate and vehicle operating conditions. The antifreeze concentration must always be a minimum of 44 percent, year-round in all climates. If percentage is lower than 44 percent, engine parts may be eroded by cavitation, and cooling system components may be severely damaged by corrosion . Maximum protection against freezing is provided with a 68% antifreeze concentration, which prevents freezing down to -67.7° C (-90° F). A higher percentage will freeze at a warmer temperature. Also, a higher percentage of antifreeze can cause the engine to overheat because the specific heat of antifreeze is lower than that of water.

Use of 100 percent ethylene-glycol will cause formation of additive deposits in the system, as the corrosion inhibitive additives in ethylene-glycol require the presence of water to dissolve. The deposits act as insulation, causing temperatures to rise to as high as 149° C (300° F). This temperature is hot enough to melt plastic and soften solder. The increased temperature can result in engine detonation. In addition, 100 percent ethylene-glycol freezes at 22° C (-8° F).

PROPYLENE-GLYCOL MIXTURES

It's overall effective temperature range is smaller than that of ethylene-glycol. The freeze point of 50/50 propylene-glycol and water is 32° C (-26° F). 5° C higher than ethylene-glycol's freeze point. The boiling point (protection against summer boil-over) of propylene-glycol is 125° C (257° F) at 96.5 kPa (14 psi), compared to 128° C (263° F) for ethylene-glycol. Use of propylene-glycol can result in boil-over or freeze-up on a cooling system designed for ethylene-glycol. Propylene glycol also has poorer heat transfer characteristics than ethylene glycol. This can increase cylinder head temperatures under certain conditions.

Propylene-glycol/ethylene-glycol Mixtures can cause the destabilization of various corrosion inhibitors, causing damage to the various cooling system components. Also, once ethylene-glycol and propylene-glycol based coolants are mixed in the vehicle, conventional methods of determining freeze point will not be accurate. Both the refractive index and specific gravity differ between ethylene glycol and propylene glycol.

DESCRIPTION - HOAT COOLANT

The cooling system is designed around the coolant. The coolant must accept heat from engine metal, in the cylinder head area near the exhaust valves and engine block. Then coolant carries the heat to the radiator where the tube/fin radiator can transfer the heat to the air.

The use of aluminum cylinder blocks, cylinder heads, and water pumps requires special corrosion protection. Mopar® Antifreeze/Coolant, 5 Year/100,000 Mile Formula (MS-9769), or the equivalent ethylene-glycol base coolant with organic corrosion inhibitors (called HOAT, for Hybrid Organic Additive Technology) is recommended. This coolant offers the best engine cooling without corrosion when mixed with 50% ethylene-glycol and 50% distilled water to obtain a freeze point of -37°C (-35°F). If it loses color or becomes contaminated, drain, flush, and replace with fresh properly mixed coolant solution.

COOLANT PERFORMANCE

The required ethylene-glycol (antifreeze) and water mixture depends upon climate and vehicle operating conditions. The coolant performance of various mixtures follows

Pure Water -Water can absorb more heat than a mixture of water and ethylene-glycol. This is for purpose of heat transfer only. Water also freezes at a higher temperature and allows corrosion.

100 percent Ethylene-Glycol -The corrosion inhibiting additives in ethylene-glycol need the presence of water to dissolve. Without water, additives form deposits in system. These act as insulation causing temperature to rise to as high as 149°C (300°F). This temperature is hot enough to melt plastic and soften solder. The increased temperature can result in engine detonation. In addition, 100 percent ethylene-glycol freezes at -22°C (-8°F).

50/50 Ethylene-Glycol and Water -Is the recommended mixture, it provides protection against freezing to -37°C (-34°F). The antifreeze concentration must always be a minimum of 44 percent, year-round in all climates. If percentage is lower, engine parts may be eroded by cavitation. Maximum protection against freezing is provided with a 68 percent antifreeze concentration, which prevents freezing down to -67.7°C (-90°F). A higher percentage will freeze at a warmer temperature. Also, a higher percentage of antifreeze can cause the engine to overheat because specific heat of antifreeze is lower than that of water.

COOLANT SELECTION AND ADDITIVES

The use of aluminum cylinder blocks, cylinder heads and water pumps requires special corrosion protection. Only Mopar® Antifreeze/Coolant, 5 Year/100,000 Mile Formula (glycol base coolant with corrosion inhibitors called HOAT, for Hybrid Organic Additive Technology) is recommended. This coolant offers the best engine cooling without corrosion when mixed with 50% distilled water to obtain to obtain a freeze point of -37°C (-35°F). If it loses color or becomes contaminated, drain, flush, and replace with fresh properly mixed coolant solution.

OPERATION

Coolant flows through the engine block absorbing the heat from the engine, then flows to the radiator where the cooling fins in the radiator transfers the heat from the coolant to the atmosphere. During cold weather the ethylene-glycol or propylene-glycol coolant prevents water present in the cooling system from freezing within temperatures indicated by mixture ratio of coolant to water.

DESCRIPTION

The coolant reserve/overflow tank is mounted on top of the fan shroud, and is made of high temperature plastic (Scheme 4)

Scheme 4

The coolant reserve/overflow system works in conjunction with the radiator pressure cap. It utilizes thermal expansion and contraction of coolant to keep coolant free of trapped air. It provides a volume for expansion and contraction of coolant. It also provides a convenient and safe method for checking coolant level and adjusting level at atmospheric pressure. This is done without removing the radiator pressure cap. The system also provides some reserve coolant to the radiator to cover minor leaks and evaporation or boiling losses.

As the engine cools, a vacuum is formed in the cooling system of both the radiator and engine. Coolant will then be drawn from the coolant tank and returned to a proper level in the radiator.

1. Remove recovery hose from radiator.
2. Remove the coolant container to fan shroud mounting bolt.
3. Tilt the container backward towards the engine to disengage the mounting pin locking features and lift the container away from the fan shroud (Scheme 4)

INSTALLATION

1. Align the coolant container mounting pins into the slots on the fan shroud and push the container onto the fan shroud.
2. Secure the container to the fan shroud with the bolt. Tighten to 8.5 N.m (75 in-lbs). NOTE: Ensure that the locking feature on the mounting pins has engaged.
3. Connect the recovery hose to the radiator (Scheme 4)

DESCRIPTION - SRT-10

The hydraulic cooling fan is integral to the fan shroud and is located between the radiator and the engine. The power steering pump supplies hydraulic fluid and pressure to rotate the cooling fan blade, while the electrical part of the fan is controlled by the PCM.

The hydraulic fan drive (motor) consists of the three major following components

1. Steering flow control valve
2. Fan control valve
3. Two stage G-rotor hydraulic drive

The hydraulic fan and drive is not serviceable separately. Therefore any failure of the fan blade, hydraulic fan drive or fan shroud requires replacement of the fan module because the fan blade and hydraulic fan drive are matched and balanced as a system and servicing either separately would disrupt this balance.

For hydraulic fluid routing information (Scheme 5)

HYDRAULIC FAN STRATEGY

The hydraulic cooling fan is controlled by the PCM. A PWM (Pulse With Modulated) signal from the PCM controls the fan from 0 to 100% of the available fan speed. There are two inputs to the PCM that determine what speed percentage of fan is required by the vehicle. These inputs are

1. Engine Coolant Temperature
2. A/C System Pressure

By monitoring these two parameters, the PCM can determine if cooling air flow is required. If air flow is required, the PCM will slowly ramp up (speed up) the fan speed until the parameter(s) are under control. Once the temperature or pressure is reduced to within operating parameters the fan will ramp up, ramp down, or hold its speed to maintain the temperature/pressure requirements.

Note. Even if the PCM is not requesting fan on operation the fan blade will usually spin between 100 and 500 RPM when the vehicle is at idle. This is due to a controlled minimum oil flow requirement through the fan drive motor.

ACTIVATING THE HYDRAULIC FAN WITH THE DRBIII®

Under the Engine Systems test heading, there is a subheading. "Hydraulic fan solenoid test", that has the selections, on/off. Activating the fan with the DRBIII® will run the fan at 100% duty cycle, which will help troubleshoot any system problems, and also help with the deaeration procedure.

Note. Engine must be running to activate the fan with the DRBIII®.

RADIATOR COOLING FAN HYDRAULIC FLUID PATH

Hydraulic fluid is pumped through the power steering pump, from the pump the fluid travels though a high pressure delivery line to the fan drive motor. As fluid is diverted through the G-rotors, rotational motion is created as fluid moves from the high-pressure (inlet) side of the motor to the low-pressure (outlet) side. Fluid exiting the drive motor is divided into two paths. Path one continues through a high pressure delivery line to the vehicles steering gear to provide steering assist. Path two sends fluid back to the power steering pump through a low pressure line. Fluid exits the steering gear under low pressure and travels through a low pressure line to the power steering fluid cooler to be cooled before being returned back the power steering fluid reservoir (Scheme 5)

Note. There is a steering flow control valve located in the fan drive motor. This valve operates like the flow control valve found in the typical power steering pump. Because of the design of the valve steering assist can not be affected by the radiator cooling fan even during fan drive failure.

Scheme 5

3.7L/4.7L/5.7L ENGINE

Scheme 6

Scheme 7

1. Disconnect negative battery cable from battery.
2. Remove coolant reserve/overflow container from fan shroud and lay aside. Do Not disconnect the hoses or drain coolant from the container.
3. The thermal viscous fan drive/fan blade assembly is attached (threaded) to the water pump hub shaft (Scheme 6) Remove the fan blade/viscous fan drive assembly from the water pump by turning the mounting nut counterclockwise as viewed from the front. Threads on the viscous fan drive are RIGHT-HAND. A 36 MM Fan Wrench should be used to prevent pulley from rotating (Scheme 7)
4. Do Not attempt to remove the fan/viscous fan drive assembly from the vehicle at this time.
5. Do Not unbolt the fan blade assembly (Scheme 6) from viscous fan drive at this time.
6. Remove the fan shroud-to-radiator mounting bolts.
7. Pull the lower shroud mounts out of the radiator tank clips.
8. Remove the fan shroud and fan blade/viscous fan drive assembly as a complete unit from vehicle.
9. After removing the fan blade/viscous fan drive assembly, do not place the viscous fan drive in a horizontal position. If stored horizontally, silicone fluid in the viscous fan drive could drain into its bearing assembly and contaminate lubricant. CAUTION: Do not remove water pump pulley-to-water pump bolts. This pulley is under spring tension.
10. Remove four bolts securing fan blade assembly to viscous fan drive (Scheme 6) CAUTION: Some engines equipped with serpentine drive belts have reverse rotating fans and viscous fan drives. They are marked with the word REVERSE to designate their usage. Installation of the wrong fan or viscous fan drive can result in engine overheating.

5.9L DIESEL

Scheme 8

Scheme 9

1. Disconnect the battery negative cables.
2. Remove fan shroud-to-engine bracket nuts. (Scheme 8) CAUTION: Do not remove the fan pulley bolts. This pulley is under spring tension.
3. The electronically controlled viscous fan drive/fan blade assembly is attached (threaded) to the fan pulley shaft (Scheme 9) Remove the fan blade/fan drive assembly from fan pulley by turning the mounting nut counterclockwise (as viewed from front). Threads on the viscous fan drive are RIGHT-HAND. A 36 MM Fan Wrench can be used. Place a bar or screwdriver between the fan pulley bolts to prevent pulley from rotating.
4. Disconnect electronically controlled fan clutch connector at lower fan shroud bracket.
5. Remove fan drive wire harness-to-lower fan shroud bracket mounting bolt. NOTE: It may be necessary to loosen the top two fan shroud brackets. Removal of the engine mounted fan shroud brackets is not necessary unless removing or installing the engine.
6. Collapse fan shroud toward front of vehicle and remove fan drive/fan blade and fan shroud as an assembly. CAUTION: The electronically controlled viscous fan drive is vibration and impact sensitive, especially at the electrical connectors. Do not drop the unit.
7. Remove fan drive wire harness support from fan shroud.
8. Remove the six fan blade-to-viscous fan drive mounting bolts.
9. Inspect the fan for cracked, chipped or damaged fan blades.

Scheme 10

Scheme 11

1. Disconnect the battery negative cables.
2. Drain the cooling system (Refer to «DRAINING COOLING SYSTEM - ALL GAS ENGINES»(/dodge/pickup-r1500/1997-2012/remont/cooling-system-mechanical/#engine-cooling-system-diagnosis-servicing-specifications__draining-cooling-system-all-gas) ).
3. Remove upper radiator hose from radiator and position out of the way.
4. Raise vehicle on hoist.
5. Disconnect the high and low pressure hydraulic hoses at the hydraulic fan motor (Scheme 10)
6. Disconnect solenoid electrical connector.
7. Lower vehicle
8. Remove air intake tube between intake moanful and air filter assembly.
9. Unclip A/C lines from radiator fan shroud, and position out of the way
10. Remove coolant recover bottle and coolant container tube.
11. Remove the four fan shroud retaining bolts.
12. Remove the fan motor and shroud assembly from the vehicle (Scheme 11)

CLEANING

Clean the fan blades using a mild soap and water. Do not use an abrasive to clean the blades.

INSPECTION

1. Install fan blade assembly to the viscous fan drive. Tighten the bolts (Scheme 6) to 24 N.m (18 ft. lbs.) torque.
2. Position the fan shroud and the fan blade/viscous fan drive assembly to the vehicle as a complete unit.
3. Install the fan shroud.
4. Install the fan blade/viscous fan drive assembly to the water pump shaft (Scheme 6) Tighten mounting nut to 50 N.m (37 ft. lbs.).
5. Install the coolant reserve/overflow container to the fan shroud.
6. Connect the negative battery cable.

Note. Viscous Fan Drive Fluid Pump Out Requirement: After installing a new viscous fan drive, bring the engine speed up to approximately 2000 RPM and hold for approximately two minutes. This will ensure proper fluid distribution within the drive.

1. Install fan blade assembly to electrically controlled viscous fan drive. Tighten mounting bolts to 24 N.m (18 ft. lbs.) torque.
2. Loosen both upper engine mounted fan shroud brackets.
3. Make sure lower engine mounted fan shroud bracket nuts are tightened to 24 N.m (18 ft. lbs.).
4. Position fan/fan drive assembly inside fan shroud and lower into position.
5. Install the viscous fan drive assembly onto fan pulley hub shaft. Tighten mounting nut to 115 N.m (85 ft. lbs.) torque.
6. Install fan shroud onto fan shroud brackets. Make sure fan drive wire harness is properly positioned. Tighten mounting nuts finger tight tight.
7. Position fan drive wire harness support onto shroud.
8. Position fan drive wire harness support locating pin into locating hole on lower fan shroud bracket. Install bolt. Tighten to 24 N.m (18 ft lbs..).
9. Connect fan drive wire harness.
10. Install fan shroud to upper engine fan shroud brackets. Tighten nut finger tight.
11. Tighten upper engine fan shroud bracket bolts to 24 N.m (18 ft. lbs.).
12. Tighten four fan shroud bracket nuts to 24 N.m (18 ft. lbs.).
13. Make sure of fan tip clearance Al the way around inside of fan shroud.
14. Connect the battery negative cables.

Note. Viscous Fan Drive Fluid Pump Out Requirement: After installing a new viscous fan drive, bring the engine speed up to approximately 2000 RPM and hold for approximately two minutes. This will ensure proper fluid distribution within the drive.

SRT-10

1. Position fan motor and shroud assembly in vehicle.
2. Install the mounting bolts. Tighten bolts to 10 N.m (98 in. lbs.)
3. Install coolant recovery bottle.
4. Raise vehicle.
5. Connect fan solenoid electrical connector.
6. Install pressure line to radiator fan motor. Tighten fitting to 47 N.m (35 ft. lbs.).
7. Install return line to radiator fan motor. Tighten fitting to 29 N.m (21 ft. lbs.)
8. Lower vehicle.
9. Fill cooling system (Refer to «REFILLING COOLING SYSTEM - ALL GAS ENGINES»(/dodge/pickup-r1500/1997-2012/remont/cooling-system-mechanical/#engine-cooling-system-diagnosis-servicing-specifications__refilling-cooling-system-all-gas) ).
10. Connect negative battery cable.
11. Fill power steering system (Refer to «STEERING»(/dodge/pickup-r1500/1997-2012/remont/manual-power-steering/#power-steering-system) ).

Note. If the solenoid removal and replacement steps are performed quickly, then only a small amount of steering fluid will drip from the radiator fan solenoid opening. The small amount of leakage should not require prior fluid removal from the power steering reservoir.

Scheme 12

1. Disconnect the battery negative cable.
2. Raise and support the vehicle.
3. Disconnect the radiator fan solenoid connector (Scheme 12)
4. Clean the area around the radiator fan solenoid of any debris.
5. While holding the solenoid body, use Torx® T40 to remove the radiator fan solenoid.

1. Make sure that the two o-rings are in place. Notice that the armature of the solenoid can rotate within the body of the solenoid.
2. Install the radiator fan solenoid into the hydraulic fan module (Scheme 12)
3. While holding the solenoid body, using a Torx® T40 tighten the radiator fan solenoid to 16.2 N.m (143 in. lbs.).
4. Connect the radiator fan solenoid connector.
5. Lower the vehicle
6. Connect the negative batter cable.
7. Check the power steering fluid level, fill as necessary.

An optional engine block heater is available with all models except SRT-10. The heater is equipped with a power cord. The cord is attached to an engine compartment component with tie-straps. The heater warms the engine providing easier engine starting and faster warm-up in low temperatures. The heater is mounted in a core hole of the engine cylinder block in place of a freeze plug with the heating element immersed in engine coolant. The 3.7L/4.7L gas powered engines have the block heater located to the rear on the right side of the engine (Scheme 13)

Scheme 13

The heater warms the engine coolant providing easier engine starting and faster warm-up in low temperatures. Connecting the power cord to a grounded 110-120 volt AC electrical outlet with a grounded three wire extension cord provides the electricity needed to heat the element.

DIAGNOSIS AND TESTING - ENGINE BLOCK HEATER

If the unit does not operate, possible causes can be either the power cord or the heater element. Test the power cord for continuity with a 110-volt voltmeter or 110-volt test light. Test heater element continuity with an ohmmeter or a 12-volt test light.

1. Disconnect the battery negative cable.
2. Drain the coolant (Refer to «DRAINING COOLING SYSTEM - ALL GAS ENGINES»(/dodge/pickup-r1500/1997-2012/remont/cooling-system-mechanical/#engine-cooling-system-diagnosis-servicing-specifications__draining-cooling-system-all-gas) ).
3. Remove the power cord from the heater by unplugging (Scheme 14)
4. Loosen (but do not completely remove) the screw at center of block heater (Scheme 14)
5. Remove the block heater by carefully prying from side-to-side. Note the direction of the heating element coil (up or down). The element coil must be installed correctly to prevent damage.

Scheme 14

1. Clean and inspect the block heater hole.
2. Install the new O-ring seal(s) to heater.
3. Insert the block heater into cylinder block and position the element properly.
4. With the heater fully seated, tighten center screw to 2 N.m (17 in. lbs.).
5. Fill the cooling system with the recommended coolant. (Refer to «REFILLING COOLING SYSTEM - ALL GAS ENGINES»(/dodge/pickup-r1500/1997-2012/remont/cooling-system-mechanical/#engine-cooling-system-diagnosis-servicing-specifications__refilling-cooling-system-all-gas) ).
6. Start and warm the engine.
7. Check the block heater for leaks.

An optional engine block heater is available on all models. The heater is equipped with a power cord. The heater is mounted in a threaded hole of the engine cylinder block with the heating element immersed in engine coolant. The cord is attached to an engine compartment component with tie-straps.

The 5.9L diesel engine has the block heater located on the right side of the engine below the exhaust manifold next to the oil cooler (Scheme 15)

Scheme 15

The heater warms the engine coolant providing easier engine starting and faster warm-up in low temperatures. Connecting the power cord to a grounded 110-120 volt AC electrical outlet with a grounded three wire extension cord provides the electricity needed to heat the element.

1. Disconnect the battery negative cables.
2. Drain coolant from radiator and cylinder block (Refer to «DRAINING COOLING SYSTEM 5.9L DIESEL ENGINE»(/dodge/pickup-r1500/1997-2012/remont/cooling-system-mechanical/#engine-cooling-system-diagnosis-servicing-specifications__draining-cooling-system-59l-diesel-engine) ).
3. Unscrew the power cord retaining cap and disconnect cord from heater element.
4. Using a suitable size socket, loosen and remove the block heater element (Scheme 16)

Scheme 16

1. Clean and inspect the threads in the cylinder block.
2. Coat heater element threads with Mopar® Thread Sealer with Teflon.
3. Screw block heater into cylinder block and tighten to 55 N.m (41 ft. lbs.).
4. Connect block heater cord and tighten retaining cap.
5. Fill cooling system with recommended coolant (Refer to «REFILLING COOLING SYSTEM 5.9L DIESEL ENGINE»(/dodge/pickup-r1500/1997-2012/remont/cooling-system-mechanical/#engine-cooling-system-diagnosis-servicing-specifications__refilling-cooling-system-59l-diesel-engine) ).
6. Start and warm the engine.
7. Check block heater for leaks.

The Engine Coolant Temperature (ECT) sensor is used to sense engine coolant temperature. The sensor protrudes into an engine water jacket.

The ECT sensor is a two-wire Negative Thermal Coefficient (NTC) sensor. Meaning, as engine coolant temperature increases, resistance (voltage) in the sensor decreases. As temperature decreases, resistance (voltage) in the sensor increases.

At key-on, the Powertrain Control Module (PCM) sends out a regulated 5 volt signal to the ECT sensor. The PCM then monitors the signal as it passes through the ECT sensor to the sensor ground (sensor return).

When the engine is cold, the PCM will operate in Open Loop cycle. It will demand slightly richer air-fuel mixtures and higher idle speeds. This is done until normal operating temperatures are reached.

The PCM uses inputs from the ECT sensor for the following calculations

1. for engine coolant temperature gauge operation through CCD or PCI (J1850) communications
2. Injector pulse-width
3. Spark-advance curves
4. ASD relay shut-down times
5. Idle Air Control (IAC) motor key-on steps
6. Pulse-width prime-shot during cranking
7. O2 sensor closed loop times
8. Purge solenoid on/off times
9. Cooling fan control
10. Temperature gauge operation
11. A/C cutoff at high coolant temperatures
12. EGR solenoid on/off times (if equipped)
13. Leak Detection Pump operation (if equipped)
14. Radiator fan relay on/off times (if equipped)
15. Target idle speed

3.7L V-6

The Engine Coolant Temperature (ECT) sensor on the 3.7L engine is installed into a water jacket at front of intake manifold near rear of generator (Scheme 17)

Scheme 17

1. Partially drain the cooling system.
2. Disconnect the electrical connector from the sensor.
3. Remove the sensor from the intake manifold.

4.7L V-8

The Engine Coolant Temperature (ECT) sensor on the 4.7L V-8 engine is located near the front of the intake manifold (Scheme 18)

Scheme 18

1. Partially drain the cooling system (Refer to «DRAINING COOLING SYSTEM - ALL GAS ENGINES»(/dodge/pickup-r1500/1997-2012/remont/cooling-system-mechanical/#engine-cooling-system-diagnosis-servicing-specifications__draining-cooling-system-all-gas) ).
2. Disconnect the electrical connector from the ECT sensor.
3. Remove the sensor from the intake manifold.

5.7L V-8

The Engine Coolant Temperature (ECT) sensor on the 5.7L engine is located under the air conditioning compressor (Scheme 19) It is installed into a water jacket at the front of the cylinder block (Scheme 20)

Scheme 19

Scheme 20

1. Partially drain the cooling system (Refer to «DRAINING COOLING SYSTEM - ALL GAS ENGINES»(/dodge/pickup-r1500/1997-2012/remont/cooling-system-mechanical/#engine-cooling-system-diagnosis-servicing-specifications__draining-cooling-system-all-gas) ).
2. Remove fan belt. Refer to «ACCESSORY DRIVE»(/dodge/pickup-r1500/1997-2012/remont/accessory-drive-belts/#accessory-drive-belt).
3. Carefully unbolt air conditioning compressor from front of engine. Do not disconnect any A/C hoses from compressor. Temporarily support compressor to gain access to ECT sensor. Refer to «A/C COMPRESSOR»(/dodge/pickup-r1500/1997-2012/remont/manual-hvac-system/#hvac-plumbing__ac-compressor) for information.
4. Disconnect electrical connector from sensor (Scheme 20)
5. Remove sensor from cylinder block.

The Engine Coolant Temperature (ECT) sensor on the 5.9L diesel engine is located near the thermostat housing (Scheme 21)

Scheme 21

1. Partially drain the cooling system (Refer to «DRAINING COOLING SYSTEM 5.9L DIESEL ENGINE»(/dodge/pickup-r1500/1997-2012/remont/cooling-system-mechanical/#engine-cooling-system-diagnosis-servicing-specifications__draining-cooling-system-59l-diesel-engine) ).
2. Disconnect the electrical connector from the sensor.
3. Remove the sensor from the cylinder head.

Scheme 22

1. Partially drain the cooling system.
2. Disconnect the electrical connector from the engine coolant temperature sensor.
3. Remove the sensor (Scheme 22)

1. Apply thread sealant to sensor threads.
2. Install sensor to engine.
3. Tighten sensor to 11 N.m (8 ft. lbs.) torque.
4. Connect electrical connector to sensor.
5. Replace any lost engine coolant. (Refer to «REFILLING COOLING SYSTEM - ALL GAS ENGINES»(/dodge/pickup-r1500/1997-2012/remont/cooling-system-mechanical/#engine-cooling-system-diagnosis-servicing-specifications__refilling-cooling-system-all-gas) ).

1. Apply thread sealant to sensor threads.
2. Install sensor to engine.
3. Tighten sensor to 11 N.m (8 ft. lbs.) torque.
4. Connect electrical connector to sensor.
5. Replace any lost engine coolant. (Refer to «REFILLING COOLING SYSTEM - ALL GAS ENGINES»(/dodge/pickup-r1500/1997-2012/remont/cooling-system-mechanical/#engine-cooling-system-diagnosis-servicing-specifications__refilling-cooling-system-all-gas) ).

1. Apply thread sealant to sensor threads.
2. Install sensor to engine.
3. Tighten sensor to 11 N.m (8 ft. lbs.) torque.
4. Connect electrical connector to sensor.
5. Replace any lost engine coolant. (Refer to «REFILLING COOLING SYSTEM - ALL GAS ENGINES»(/dodge/pickup-r1500/1997-2012/remont/cooling-system-mechanical/#engine-cooling-system-diagnosis-servicing-specifications__refilling-cooling-system-all-gas) ).

1. Install sensor to engine.
2. Tighten sensor to 11 N.m (8 ft. lbs.) torque.
3. Connect electrical connector to sensor.
4. Replace any lost engine coolant. (Refer to «REFILLING COOLING SYSTEM 5.9L DIESEL ENGINE»(/dodge/pickup-r1500/1997-2012/remont/cooling-system-mechanical/#engine-cooling-system-diagnosis-servicing-specifications__refilling-cooling-system-59l-diesel-engine) ).

8.3L V-10

1. Apply thread sealant to sensor threads.
2. Install sensor to engine.
3. Tighten sensor to 11 N.m (8 ft. lbs.) torque.
4. Connect electrical connector to sensor.
5. Replace any lost engine coolant. (Refer to «REFILLING COOLING SYSTEM - ALL GAS ENGINES»(/dodge/pickup-r1500/1997-2012/remont/cooling-system-mechanical/#engine-cooling-system-diagnosis-servicing-specifications__refilling-cooling-system-all-gas) ).

3.7L/4.7L ENGINE

A pellet-type thermostat controls the operating temperature of the engine by controlling the amount of coolant flow to the radiator. On all engines the thermostat is closed below 195°F (90°C). Above this temperature, coolant is allowed to flow to the radiator. This provides quick engine warm up and overall temperature control. On the 3.7L4.7L engine the thermostat is designed to block the flow of the coolant bypass journal by 50% instead of completely blocking the flow. This design controls coolant temperature more accurately (Scheme 23)

Scheme 23

The same thermostat is used for winter and summer seasons. An engine should not be operated without a thermostat, except for servicing or testing. Operating without a thermostat causes other problems. These are: longer engine warmup time, unreliable warmup performance, increased exhaust emissions and crankcase condensation. This condensation can result in sludge formation.

5.7L ENGINE

The thermostat on the 5.7L gas powered engine is located behind the thermostat housing at the front of the intake manifold (Scheme 24)

Scheme 24

The thermostat is a wax pellet driven, reverse poppet choke type.

Coolant leakage into the pellet container will cause the thermostat to fail in the open position. Thermostats very rarely stick. Do not attempt to free a thermostat with a prying device.

The same thermostat is used for winter and summer seasons. An engine should not be operated without a thermostat, except for servicing or testing. Operating without a thermostat causes longer engine warmup time, unreliable warmup performance, increased exhaust emissions and crankcase condensation that can result in sludge formation.

The thermostat of the 5.9L diesel engine is located in the front of the cylinder head, underneath the thermostat housing (Scheme 25)

Scheme 25

The same thermostat is used for winter and summer seasons. An engine should not be operated without a thermostat, except for servicing or testing. Operating without a thermostat will cause overheating.

The wax pellet is located in a sealed container at the spring end of the thermostat. When heated, the pellet expands, overcoming closing spring tension and water pump pressure to force the valve to open.

ON-BOARD DIAGNOSTICS - GAS ENGINES

All gasoline powered models are equipped with On-Board Diagnostics for certain cooling system components. Refer to ON-BOARD DIAGNOSTICS (OBD) in the Diagnosis section of this group for additional information. If the powertrain control module (PCM) detects low engine coolant temperature, it will record a Diagnostic Trouble Code (DTC) in the PCM memory. Do not change a thermostat for lack of heat as indicated by the instrument panel gauge or by poor heater performance unless a DTC is present. Refer to the DIAGNOSIS AND TESTING for other probable causes.

The DTC can also be accessed through the DRBIII® scan tool. Refer to POWERTRAIN DIAGNOSTIC PROCEDURES (PART 1) for diagnostic information and operation of the DRBIII® scan tool.

DIESEL ENGINE

The cooling system used with the diesel engine provides the extra coolant capacity and extra cooling protection needed for higher GVWR (Gross Vehicle Weight Rating) and GCWR (Gross Combined Weight Rating) vehicles.

This system capacity will not effect warm up or cold weather operating characteristics if the thermostat is operating properly. This is because coolant will be held in the engine until it reaches the thermostat "set" temperature.

Diesel engines, due to their inherent efficiency are slower to warm up than gasoline powered engines, and will operate at lower temperatures when the vehicle is unloaded. Because of this, lower temperature gauge readings for diesel versus gasoline engines may, at times be normal.

Typically, complaints of low engine coolant temperature are observed as low heater output when combined with cool or cold outside temperatures.

To help promote faster engine warm-up, the electric engine block heater must be used with cool or cold outside temperatures. This will help keep the engine coolant warm when the vehicle is parked.

A "Cold Weather Cover" is available from the parts department through the Mopar Accessories product line. This accessory cover is designed to block airflow entering the radiator and engine compartment to promote faster engine warm-up. It attaches to the front of the vehicle at the grill opening. The cover is to be used with cool or cold temperatures only. If used with high outside temperatures, serious engine damage could result. Refer to the literature supplied with the cover for additional information.

1. To determine if the thermostat is defective, it must be removed from the vehicle (Refer to «REMOVAL»(/dodge/pickup-r1500/1997-2012/remont/cooling-fan/#engine-cooling-system-removal-installtion) ).
2. After the thermostat has been removed, examine the thermostat and inside of thermostat housing for contaminants. If contaminants are found, the thermostat may already be in a "stuck open" position. Flush the cooling system before replacing thermostat (Refer to «COOLING SYSTEM CLEANING/REVERSE FLUSHING»(/dodge/pickup-r1500/1997-2012/remont/cooling-system-mechanical/#engine-cooling-system-diagnosis-servicing-specifications) ).
3. Place the thermostat into a container filled with water.
4. Place the container on a hot plate or other suitable heating device.
5. Place a commercially available radiator thermometer into the water.
6. Apply heat to the water while observing the thermostat and thermometer.
7. The thermostat will begin to open at 85.5 - 89.4°C. (186 - 193°F). If the valve starts to move before this temperature is reached, it is opening too early. Replace thermostat. The thermostat should be fully open (valve will stop moving) at 97°C (207°F). If the valve is still moving when the water temperature reaches 97°C (207°F), it is opening too late. Replace thermostat. If the valve refuses to move at any time, replace thermostat.

REMOVAL - 3.7/4.7L

Do not waste reusable coolant. If the solution is clean, drain the coolant into a clean container for reuse.

If the thermostat is being replaced, be sure that the replacement is the specified thermostat for the vehicle model and engine type.

Scheme 26

1. Disconnect the negative battery cable.
2. Drain the cooling system (Refer to «DRAINING COOLING SYSTEM - ALL GAS ENGINES»(/dodge/pickup-r1500/1997-2012/remont/cooling-system-mechanical/#engine-cooling-system-diagnosis-servicing-specifications__draining-cooling-system-all-gas) ).
3. Raise and support the vehicle.
4. Remove the splash shield.
5. Remove the lower radiator hose clamp and the lower radiator hose at the thermostat housing.
6. Remove the thermostat housing mounting bolts, thermostat housing and thermostat (Scheme 26)

REMOVAL - 5.7L

Do not waste reusable coolant. If the solution is clean, drain the coolant into a clean container for reuse.

If the thermostat is being replaced, be sure that the replacement is the specified thermostat for the vehicle model and engine type.

Factory installed thermostat housings on 5.9L engine is installed on a gasket with an anti-stick coating. This will aid in gasket removal and clean-up.

Scheme 27

Scheme 28

Scheme 29

Scheme 30

1. Disconnect the negative battery cable.
2. Drain the cooling system until the coolant level is below the thermostat (Refer to «DRAINING COOLING SYSTEM - ALL GAS ENGINES»(/dodge/pickup-r1500/1997-2012/remont/cooling-system-mechanical/#engine-cooling-system-diagnosis-servicing-specifications__draining-cooling-system-all-gas) ).
3. Air Conditioned vehicles: Remove the support bracket (generator mounting bracket-to-intake manifold) located near the rear of the generator (Scheme 27) NOTE: On air conditioning equipped vehicles, the generator must be partially removed.
4. Remove the accessory drive belt (Refer to «ACCESSORY DRIVE»(/dodge/pickup-r1500/1997-2012/remont/accessory-drive-belts/#accessory-drive-belt) ) (Scheme 28)
5. Remove the generator mounting bolts. Do not remove any of the wiring at the generator. If equipped with 4WD, unplug the 4WD indicator lamp wiring harness (located near rear of generator).
6. Remove the generator. Position the generator to gain access for the thermostat gasket removal. WARNING: CONSTANT TENSION HOSE CLAMPS ARE USED ON MOST COOLING SYSTEM HOSES. WHEN REMOVING OR INSTALLING, USE ONLY TOOLS DESIGNED FOR SERVICING THIS TYPE OF CLAMP. ALWAYS WEAR SAFETY GLASSES WHEN SERVICING CONSTANT TENSION CLAMPS. CAUTION: A number or letter is stamped into the tongue of the constant tension clamps (Scheme 29) If replacement is necessary, use only an original equipment clamp with a matching number, letter and width.
7. Remove the radiator upper hose clamp and upper hose at the thermostat housing.
8. Position the wiring harness (behind thermostat housing) to gain access to the thermostat housing.
9. Remove the thermostat housing mounting bolts, thermostat housing, gasket and thermostat (Scheme 30) Discard old gasket.

REMOVAL - 5.9L DIESEL

Do not waste reusable coolant. If the solution is clean, drain the coolant into a clean container for reuse.

Scheme 31

1. Disconnect the battery negative cables.
2. Drain cooling system until coolant level is below thermostat (Refer to «DRAINING COOLING SYSTEM 5.9L DIESEL ENGINE»(/dodge/pickup-r1500/1997-2012/remont/cooling-system-mechanical/#engine-cooling-system-diagnosis-servicing-specifications__draining-cooling-system-59l-diesel-engine) ). WARNING: CONSTANT TENSION HOSE CLAMPS ARE USED ON MOST COOLING SYSTEM HOSES. WHEN REMOVING OR INSTALLING, USE ONLY TOOLS DESIGNED FOR SERVICING THIS TYPE OF CLAMP, SUCH AS SPECIAL CLAMP TOOL 6094. CAUTION: A number or letter is stamped into the tongue of constant tension clamps. If replacement is necessary, use only an original equipment clamp with a matching number or letter.
3. Remove radiator hose clamp and hose from thermostat housing.
4. Remove the three (3) water outlet-to-cylinder head bolts and remove the water outlet connector (Scheme 31)
5. Clean the mating surfaces of the water outlet connector and clean the thermostat seat groove at the top of the thermostat housing (Scheme 31)

INSTALLATION - 3.7/4.7L

1. Clean the mating areas of the timing chain cover and the thermostat housing.
2. Install the thermostat (spring side down) into the recessed machined groove on the timing chain cover (Scheme 26)
3. Position the thermostat housing on the timing chain cover.
4. Install the housing-to-timing chain cover bolts. Tighten the bolts to 13 N.m (112 in. lbs.). CAUTION: The housing must be tightened evenly and the thermostat must be centered into the recessed groove in the timing chain cover. If not, it may result in a cracked housing, damaged timing chain cover threads or coolant leaks.
5. Install the lower radiator hose on the thermostat housing.
6. Install the splash shield.
7. Lower the vehicle.
8. Fill the cooling system (Refer to «REFILLING COOLING SYSTEM - ALL GAS ENGINES»(/dodge/pickup-r1500/1997-2012/remont/cooling-system-mechanical/#engine-cooling-system-diagnosis-servicing-specifications__refilling-cooling-system-all-gas) ).
9. Connect negative battery cable.
10. Start and warm the engine. Check for leaks.

Scheme 32

Scheme 33

1. Clean the mating areas of the intake manifold and thermostat housing.
2. Install the thermostat (spring side down) into the recessed machined groove on the intake manifold (Scheme 30)
3. Install the gasket on the intake manifold and over the thermostat (Scheme 30)
4. Position the thermostat housing to the intake manifold. NOTE: The word FRONT stamped on housing (Scheme 32) For adequate clearance, this must be placed towards the front of the vehicle. The housing is slightly angled forward after the installation to the intake manifold.
5. Install the housing-to-intake manifold bolts. Tighten the bolts to 23 N.m (200 in. lbs.).
6. Install the radiator upper hose to the thermostat housing. CAUTION: When installing the serpentine accessory drive belt, the belt must be routed correctly. If not, the engine may overheat due to the water pump rotating in wrong direction. (Scheme 33) for the correct 5.9L engine belt routing. The correct belt with correct length must be used.
7. Air Conditioned vehicles; Install the generator. Tighten the bolts to 41 N.m (30 ft. lbs.).
8. Install the support bracket (generator mounting bracket-to-intake manifold). (Scheme 27) Tighten the bolts to 54 N.m (40 ft. lbs.).
9. Install the accessory drive belt (Scheme 28) (Refer to «ACCESSORY DRIVE»(/dodge/pickup-r1500/1997-2012/remont/accessory-drive-belts/#accessory-drive-belt) ).
10. Fill the cooling system (Refer to «REFILLING COOLING SYSTEM - ALL GAS ENGINES»(/dodge/pickup-r1500/1997-2012/remont/cooling-system-mechanical/#engine-cooling-system-diagnosis-servicing-specifications__refilling-cooling-system-all-gas) ).
11. Connect battery negative cable.
12. Start and warm the engine. Check for leaks.

INSTALLATION - 5.9L DIESEL

1. Inspect thermostat seal for cuts or nicks. Replace if damaged.
2. Install the thermostat into the groove in the top of the cylinder head (Scheme 31)
3. Install the thermostat housing and bolts. Tighten the bolts to 10 N.m (89 in. lbs.) torque.
4. Install the radiator upper hose and clamp.
5. Fill the cooling system with coolant (Refer to «REFILLING COOLING SYSTEM 5.9L DIESEL ENGINE»(/dodge/pickup-r1500/1997-2012/remont/cooling-system-mechanical/#engine-cooling-system-diagnosis-servicing-specifications__refilling-cooling-system-59l-diesel-engine) ).
6. Connect the battery negative cables.
7. Start the engine and check for coolant leaks. Run engine to check for proper thermostat operation.

The thermal viscous fan drive (Scheme 34) 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.

Scheme 34

A thermostatic bimetallic spring coil is located on the front face of the viscous fan drive unit (a typical viscous unit is shown in (Scheme 35) 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.

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.

Scheme 35

NOISE

Note. It is normal for fan noise to be louder (roaring) when

1. The underhood temperature is above the engagement point for the viscous drive coupling. This may occur when ambient (outside air temperature) is very high.
2. Engine loads and temperatures are high such as when towing a trailer.
3. Cool silicone fluid within the fan drive unit is being redistributed back to its normal disengaged (warm) position. This can occur during the first 15 seconds to one minute after engine start-up on a cold engine.

LEAKS

Viscous fan drive operation is not affected by small oil stains near the drive bearing. If leakage appears excessive, replace the fan drive unit.

VISCOUS DRIVE

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.

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. The timing light is to be used as a strobe light. This step cannot be used on the diesel engine.
4. Block the air flow through the radiator. Secure a sheet of plastic in front of the radiator. 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) and blower fan 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 88° C (190° F). Fan drive engagement should start to occur at/between: 3.7L Automatic - 93° C - 99°C (200° F - 210° F) 3.7L Manual/4.7L Automatic/5.9L - 85° - 91° C (185° - 195° F) 4.7L Manual - 74° - 79° C (165° - 175° F) 5.7L 5.9L 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 viscous drive engagement is verified, remove the plastic sheet. Fan drive disengagement should start to occur at or between: 3.7L Automatic - 76°C - 81°C (168° F - 178° F) 3.7L Manual/4.7L Auto/ 5.9L - 67°C - 73°C (153° F - 163° F) 4.7L Manual - 56°C - 62°C (133° F - 143° F) 5.7L 5.9L 8.0L engine - 93° to 101° C (190° - 205° F) Minimum 73°C (163°F). A definite decrease of fan flow noise (roaring) should be noticed. If not, replace the defective viscous fan drive unit. CAUTION: Some engines equipped with serpentine drive belts have reverse rotating fans and viscous fan drives. They are marked with the word REVERSE to designate their usage. Installation of the wrong fan or viscous fan drive can result in engine overheating. 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 electronically controlled viscous fan drive (Scheme 37) and (Scheme 36) is attached to the fan drive pulley mounted to the engine. The coupling allows the fan to be driven in a normal manner. The fan speed is controlled by the electronic control module.

The Engine Control Module (ECM) controls the level of engagement of the electronically controlled viscous fan clutch by monitoring coolant temperature, intake manifold temperature, and air conditioning status. Based on cooling requirements, the ECM sends a signal to the viscous fan clutch to increase or decrease the fan speed.

Fan speed is monitored by the ECM. Fan speeds above or below a calibrated threshold will set a DTC. Circuit concerns will also set fan clutch DTC's.

Scheme 36

Scheme 37

Note. It is normal for fan noise to be louder (roaring) when

1. Fan duty cycle high. This may occur when ambient (outside air temperature) is very high.
2. Engine loads and temperatures are high such as when towing a trailer.
3. Aggressive engine braking down a steep grade where transmission temperatures may be high
4. Cool silicone fluid within the fan drive unit is being redistributed back to its normal disengaged (warm) position. This can occur during the first 15 seconds to one minute after engine start-up on a cold engine.

Viscous fan drive operation is not affected by small oil stains near the drive bearing. If leakage appears excessive, replace the fan drive unit.

ELECTRONICALLY CONTROLLED VISCOUS DRIVE

If the fan assembly free-wheels without drag (the fan blades will revolve more than five turns when spun by hand), do not replace the fan drive. This spin test must be performed when the engine is cool.

If the fan assembly does not free-wheel and a metallic grinding sound exists, replace the electronically controlled fan drive (Refer to REMOVAL ).

Note. The following test may take up to 15 minutes to perform.

The engine should be at normal operating temperature.

Scheme 38

1. Set the parking brake and verify the transmission is in park or neutral.
2. Set air conditioner (if equipped) and blower fan to OFF.
3. Start and allow engine to reach normal operating temperatures.
4. Stop engine, connect the DRB III and select appropriate model year and engine option.
5. Check for and correct existing DTC's
6. Using Tool 6801, connect pin 1 of the electronically controlled viscous fan drive connector, located at the lower fan shroud to battery ground (Scheme 38)
7. Using the DRB III, verify that DTC 0480 set.
8. Start the engine.
9. Go to the SENSOR screen and observe the fan speed.
10. Run the engine at 2500 RPM. NOTE: It maybe take 15 minutes before fan speed increases.
11. The fan speed should increase according to the «ELECTRONICALLY CONTROLLED VISCOUS FAN DRIVE SPEEDS»(/dodge/pickup-r1500/1997-2012/remont/cooling-fan/#engine-cooling-system-removal-installtion) table.
12. If fan speed does not increase, replace the electronically control viscous fan drive. ELECTRONICALLY CONTROLLED VISCOUS FAN DRIVE SPEEDS ENGINE RPM FAN RPM (Min) 500 490 1000 950 1500 1420 2000 1850 2500 2230 3000 2440
13. If the fan speed does increase and there is still a concern, refer to the «POWERTRAIN DIAGNOSTIC PROCEDURES (PART 1)»(/dodge/pickup-r1500/1997-2012/remont/communication-devices/#powertrain-diagnostic-procedures-part-1) to diagnosis the electronically controlled viscous fan drive control circuit. CAUTION: If the viscous fan drive is replaced because of mechanical damage, the cooling fan blades should also be inspected. Inspect for fatigue cracks or chips that could result in excessive vibration. Replace fan blade assembly if any of these conditions are found.

The radiator is a aluminum cross-flow design with horizontal tubes through the radiator core and vertical plastic side tanks (Scheme 40)

This radiator does not contain an internal transmission oil cooler.

The radiator supplies sufficient heat transfer using the cooling fins interlaced between the horizontal tubes in the radiator core to cool the engine.

RADIATOR COOLANT FLOW

Use the following procedure to determine if coolant is flowing through the cooling system.

1. Idle engine until operating temperature is reached. If the upper radiator hose is warm to the touch, the thermostat is opening and coolant is flowing to the radiator. WARNING: HOT, PRESSURIZED COOLANT CAN CAUSE INJURY BY SCALDING. USING A RAG TO COVER THE RADIATOR PRESSURE CAP, OPEN RADIATOR CAP SLOWLY TO THE FIRST STOP. THIS WILL ALLOW ANY BUILT-UP PRESSURE TO VENT TO THE RESERVE/OVERFLOW TANK. AFTER PRESSURE BUILD-UP HAS BEEN RELEASED, REMOVE CAP FROM FILLER NECK.
2. Drain a small amount of coolant from the radiator until the ends of the radiator tubes are visible through the filler neck. Idle the engine at normal operating temperature. If coolant is flowing past the exposed tubes, the coolant is circulating.

Scheme 39

Scheme 40

1. Disconnect battery negative cables. WARNING: DO NOT REMOVE THE CYLINDER BLOCK DRAIN PLUGS OR LOOSEN THE RADIATOR DRAINCOCK WITH THE SYSTEM HOT AND UNDER PRESSURE. SERIOUS BURNS FROM THE COOLANT CAN OCCUR.
2. Drain the cooling system (Refer to «DRAINING COOLING SYSTEM - ALL GAS ENGINES»(/dodge/pickup-r1500/1997-2012/remont/cooling-system-mechanical/#engine-cooling-system-diagnosis-servicing-specifications__draining-cooling-system-all-gas) ). WARNING: CONSTANT TENSION HOSE CLAMPS ARE USED ON MOST COOLING SYSTEM HOSES. WHEN REMOVING OR INSTALLING, USE ONLY TOOLS DESIGNED FOR SERVICING THIS TYPE OF CLAMP. ALWAYS WEAR SAFETY GLASSES WHEN SERVICING CONSTANT TENSION CLAMPS. CAUTION: A number or letter is stamped into the tongue of constant tension clamps. If replacement is necessary, use only an original equipment clamp with a matching number or letter and the correct width.
3. Remove the hose clamps and hoses from radiator.
4. Remove the coolant reserve/overflow tank hose from the radiator filler neck.
5. Remove the coolant reserve/overflow tank from the fan shroud (pull straight up). The tank slips into slots on the fan shroud.
6. Unclip the power steering hoses from the fan shroud.
7. Disconnect the electrical connectors at the windshield washer reservoir tank and remove the tank.
8. Remove the fan shroud mounting bolts and pull up and out of the radiator tank clips (Scheme 39) Position shroud rearward over the fan blades towards engine.
9. Disconnect the transmission cooler lines from the transmission cooler, then plug the transmission lines and cooler to prevent leakage.
10. Disconnect the power steering lines from the power steering cooler, then plug the power steering lines and cooler to prevent leakage.
11. Remove the two radiator upper mounting bolts (Scheme 40)
12. Lift the radiator straight up and out of the engine compartment. Take care not to damage cooling fins or tubes on the radiator and oil coolers when removing. NOTE: The radiator is equipped with one alignment dowel on the bottom of the outlet tank and one retaining bracket on the front side of the inlet tank. Both features have rubber insulators attached to them that must be present. The alignment dowel fits into a hole at the bottom of the front end sheet metal vertical support post and the support bracket rests on top of the lower radiator closure tube.

Clean radiator fins are necessary for good heat transfer. The radiator and oil cooler fins should be cleaned when an accumulation of debris has occurred. With the engine cold, apply cold water and compressed air to the back (engine side) of the radiator to flush the radiator and/or oil coolers of debris.

Inspect the radiator side tanks for cracks, and broken or missing fittings. Inspect the joint where the tanks seam up to the radiator core for signs of leakage and/or deteriorating seals.

Inspect radiator core for corroded, bent or missing cooling fins. Inspect the core for bent or damaged cooling tubes.

1. Position the fan shroud over the fan blades rearward towards engine.
2. Install the rubber insulators to the lower radiator mounting features (alignment dowel and support bracket at the lower part of the radiator).
3. Lower the radiator into position while guiding the alignment dowel into the vertical post bracket. Position and seat the lower radiator support bracket onto the lower radiator closure tube.
4. Install the upper radiator mounting bolts. Tighten bolts to 10 N.m (90 in. lbs.).
5. Connect the lower radiator hose and install the clamp in the proper position.
6. Connect the power steering hoses to the power steering oil cooler and install the clamps.
7. Connect the transmission oil cooler lines to the transmission oil cooler and install the secondary latches.
8. Position the fan shroud into the mounting clips on the radiator tanks and secure with bolts. Tighten the bolts to 8.5 N.m (75 in. lbs.).
9. Secure the power steering hoses into the clip on the lower fan shroud.
10. Install the windshield washer reservoir tank and connect the hose and electrical connector.
11. Install coolant reserve/overflow container hose(s) to radiator filler neck and secure properly with clamps.
12. Install coolant reserve/overflow container or degas container to fan shroud and tighten the bolts to 8.5 N.m (75 in. lbs.).
13. Connect upper radiator hose and install clamp.
14. Install battery negative cable.
15. Fill cooling system with coolant (Refer to «REFILLING COOLING SYSTEM - ALL GAS ENGINES»(/dodge/pickup-r1500/1997-2012/remont/cooling-system-mechanical/#engine-cooling-system-diagnosis-servicing-specifications__refilling-cooling-system-all-gas) ).
16. Operate the engine until it reaches normal operating temperature. Check cooling system fluid levels.

The radiator is a aluminum cross-flow design with horizontal tubes through the radiator core and vertical plastic side tanks (Scheme 41)

This radiator does not contain an internal transmission oil cooler.

The radiator supplies sufficient heat transfer using the cooling fins interlaced between the horizontal tubes in the radiator core to cool the engine.

Use the following procedure to determine if coolant is flowing through the cooling system.

1. Idle engine until operating temperature is reached. If the upper radiator hose is warm to the touch, the thermostat is opening and coolant is flowing to the radiator. WARNING: HOT, PRESSURIZED COOLANT CAN CAUSE INJURY BY SCALDING. USING A RAG TO COVER THE RADIATOR PRESSURE CAP, OPEN RADIATOR CAP SLOWLY TO THE FIRST STOP. THIS WILL ALLOW ANY BUILT-UP PRESSURE TO VENT TO THE RESERVE/OVERFLOW TANK. AFTER PRESSURE BUILD-UP HAS BEEN RELEASED, REMOVE CAP FROM FILLER NECK.
2. Drain a small amount of coolant from the radiator until the ends of the radiator tubes are visible through the filler neck. Idle the engine at normal operating temperature. If coolant is flowing past the exposed tubes, the coolant is circulating.

Scheme 41

1. Disconnect both battery negative cables. WARNING: DO NOT REMOVE THE CYLINDER BLOCK DRAIN PLUGS OR LOOSEN THE RADIATOR DRAINCOCK WITH THE SYSTEM HOT AND UNDER PRESSURE. SERIOUS BURNS FROM COOLANT CAN OCCUR.
2. Drain the cooling system (Refer to «DRAINING COOLING SYSTEM 5.9L DIESEL ENGINE»(/dodge/pickup-r1500/1997-2012/remont/cooling-system-mechanical/#engine-cooling-system-diagnosis-servicing-specifications__draining-cooling-system-59l-diesel-engine) ). WARNING: CONSTANT TENSION HOSE CLAMPS ARE USED ON MOST COOLING SYSTEM HOSES. WHEN REMOVING OR INSTALLING, USE ONLY TOOLS DESIGNED FOR SERVICING THIS TYPE OF CLAMP, SUCH AS SPECIAL CLAMP TOOL (NUMBER 6094). ALWAYS WEAR SAFETY GLASSES WHEN SERVICING CONSTANT TENSION CLAMPS. CAUTION: A number or letter is stamped into the tongue of constant tension clamps. If replacement is necessary, use only an original equipment clamp with a matching number or letter.
3. Remove air box and turbocharger inlet tube.
4. Remove coolant tank hose, washer bottle hose and the positive battery cable from the fastening clips located on top of the radiator.
5. Remove hose clamps and hoses from radiator.
6. Remove the power steering cooler mounting bolts and position the power steering cooler out of the way.
7. Disconnect the transmission cooler lines at the transmission cooler. The transmission cooler will remain on the radiator and can be removed as an assembly.
8. Remove the two radiator upper mounting bolts (Scheme 41)
9. Tilt radiator toward front of vehicle and lift out of engine compartment. The bottom of the radiator is equipped with two alignment dowels that fit into holes in the lower radiator support panel. Rubber biscuits (insulators) are installed to these dowels. Take care not to damage cooling fins or tubes on the radiator and air conditioning condenser or the electronic viscous fan connector when removing.

Clean radiator fins are necessary for good heat transfer. The radiator and oil cooler fins should be cleaned when an accumulation of debris has occurred. With the engine cold, apply cold water and compressed air to the back (engine side) of the radiator to flush the radiator and/or oil coolers of debris.

Inspect the radiator side tanks for cracks, and broken or missing fittings. Inspect the joint where the tanks seam up to the radiator core for signs of leakage and/or deteriorating seals.

Inspect radiator core for corroded, bent or missing cooling fins. Inspect the core for bent or damaged cooling tubes.

Scheme 42

1. Install rubber insulators to alignment dowels at lower part of radiator.
2. Lower the radiator into position while guiding the two alignment dowels into lower radiator support. Different alignment holes are provided in the lower radiator support for each engine application.
3. Install two upper radiator mounting bolts. Tighten bolts to 11.8 N.m (105 in. lbs.) torque.
4. Connect both radiator hoses and install hose clamps.
5. Connect transmission cooler lines to transmission cooler. Inspect quick connect fittings for debris and install until an audible "click" is heard. Pull apart to verify connection.
6. Position power steering cooler on the radiator and tighten nuts to 10 N.m (90 in. lbs.)
7. Position the electronic viscous fan wiring in the channel in the upper shroud (Scheme 42) Make sure that the grommet seats into the channel.
8. Install lower radiator shroud using two push pins. Make sure the wiring viscous fan drive wiring is not pinched.
9. Install the wiring harness bracket to the upper shroud.
10. Connect the viscous fan drive wiring to the wiring harness.
11. Install the coolant recovery container (Refer to «INSTALLATION»(/dodge/pickup-r1500/1997-2012/remont/cooling-fan/#engine-cooling-system-removal-installtion__installation) ).
12. Position coolant recovery tank hose, washer bottle hose and the positive battery cable into the clips located on the top of the radiator.
13. Install air box and turbocharger inlet hose. Tighten clamps to 4 N.m (35 in. lbs.).
14. Position heater controls to full heat position.
15. Fill cooling system with coolant (Refer to «REFILLING COOLING SYSTEM 5.9L DIESEL ENGINE»(/dodge/pickup-r1500/1997-2012/remont/cooling-system-mechanical/#engine-cooling-system-diagnosis-servicing-specifications__refilling-cooling-system-59l-diesel-engine) ).
16. Operate engine until it reaches normal temperature. Check cooling system and automatic transmission (if equipped) fluid levels.

Scheme 43

Scheme 44

1. Disconnect both battery negative cables.
2. Drain the cooling system (Refer to «DRAINING COOLING SYSTEM - ALL GAS ENGINES»(/dodge/pickup-r1500/1997-2012/remont/cooling-system-mechanical/#engine-cooling-system-diagnosis-servicing-specifications__draining-cooling-system-all-gas) ). WARNING: CONSTANT TENSION HOSE CLAMPS ARE USED ON MOST COOLING SYSTEM HOSES. WHEN REMOVING OR INSTALLING, USE ONLY TOOLS DESIGNED FOR SERVICING THIS TYPE OF CLAMP. ALWAYS WEAR SAFETY GLASSES WHEN SERVICING CONSTANT TENSION CLAMPS.
3. Remove radiator fan (Refer to «REMOVAL»(/dodge/pickup-r1500/1997-2012/remont/cooling-fan/#engine-cooling-system-removal-installtion) ).
4. Remove the power steering cooler mounting bolts and position the power steering cooler out of the way. (Scheme 43)
5. Lower vehicle.
6. Remove the two radiator upper mounting bolts.
7. Lift radiator straight up and out of engine compartment. The bottom of the radiator is equipped with two alignment dowels that fit into holes in the lower radiator support panel. Rubber biscuits (insulators) are installed to these dowels. Take care not to damage cooling fins or tubes on the radiator and air conditioning condenser when removing. (Scheme 44)

1. Install rubber insulators to alignment dowels at lower part of radiator.
2. Lower the radiator into position while guiding the two alignment dowels into lower radiator support. Different alignment holes are provided in the lower radiator support for each engine application.
3. Install two upper radiator mounting bolts. Tighten bolts to 11.8 N.m (105 in. lbs.) torque.
4. Install radiator fan and shroud assembly (Refer to «INSTALLATION»(/dodge/pickup-r1500/1997-2012/remont/cooling-fan/#engine-cooling-system-removal-installtion) ).
5. Install the coolant recovery container (Refer to «INSTALLATION»(/dodge/pickup-r1500/1997-2012/remont/cooling-fan/#engine-cooling-system-removal-installtion__installation) ).
6. Install upper radiator hose.
7. Raise vehicle.
8. Install pressure line to radiator fan motor. Tighten fitting to 47 N.m (35 ft. lbs.).
9. Install return line to radiator fan motor. Tighten fitting to 29 N.m (21 ft. lbs.)
10. Install lower radiator hoses.
11. Connect transmission cooler lines to transmission cooler.
12. Position power steering cooler on the radiator and tighten nuts to 10 N.m (90 in. lbs.)
13. Lower vehicle.
14. Install air box and inlet hose. Tighten clamps to 4 N.m (35 in. lbs.).
15. Fill cooling system (Refer to «REFILLING COOLING SYSTEM - ALL GAS ENGINES»(/dodge/pickup-r1500/1997-2012/remont/cooling-system-mechanical/#engine-cooling-system-diagnosis-servicing-specifications__refilling-cooling-system-all-gas) ).
16. Connect negative battery cable.
17. Fill power steering system (Refer to «STEERING»(/dodge/pickup-r1500/1997-2012/remont/manual-power-steering/#power-steering-system) ).
18. Operate engine until it reaches normal temperature. Check cooling system and automatic transmission (if equipped) fluid levels.

All cooling systems are equipped with a pressure cap (Scheme 45) For 5.9L engines, the pressure cap is located on top of the radiator outlet tank. For all other engines, the pressure cap is located on top of the coolant degas container. The cap releases pressure at some point within a range of 97-to-124 kPa (14-to-18 psi). The pressure relief point (in pounds) is engraved on top of the cap

The cooling system will operate at pressures slightly above atmospheric pressure. This results in a higher coolant boiling point allowing increased radiator cooling capacity. The cap contains a spring-loaded pressure relief valve. This valve opens when system pressure reaches the release range of 97-to-124 kPa (14-to-18 psi).

A rubber gasket seals the radiator filler neck. This is done to maintain vacuum during coolant cool-down and to prevent leakage when system is under pressure.

Scheme 45

A vent valve in the center of the cap will remain shut as long as the cooling system is pressurized. As the coolant cools, it contracts and creates a vacuum in the cooling system. This causes the vacuum valve to open and coolant in the reserve/overflow container to be drawn through the recovery hose connecting the filler neck and reserve/overflow container. If the vacuum valve is stuck shut, or the recovery hose is kinked, radiator hoses will collapse on cool down.

DIAGNOSIS AND TESTING - RADIATOR CAP-TO-FILLER NECK SEAL

The pressure cap upper gasket (seal) pressure relief can be tested by removing overflow hose from the radiator filler neck tube. Attach the hose of the pressure tester tool 7700 (or equivalent) to the tube. It will be necessary to disconnect hose from its adapter for the filler neck. Pump air into radiator. The pressure cap upper gasket should relieve at 69 to 124kPa (10 to 18 psi) and hold pressure at a minimum of 55 kPa (8 psi).

Do not remove the radiator cap at any time except for the following purposes

1. Check and adjust antifreeze freeze point.
2. Refill the system with new antifreeze.
3. Conducting service procedures.
4. Checking for vacuum leaks.

RADIATOR CAP

Remove the cap from the radiator. Be sure that the sealing surfaces are clean. Moisten the rubber gasket with water and install the cap on the pressure tester 7700 or an equivalent (Scheme 46)

Operate the tester pump to bring the pressure to 104 kPa (15 psi) on the gauge. If the pressure cap fails to hold pressure of at least 97 kPa (14 psi) replace the cap. Refer to the following CAUTION .

The pressure cap may test properly while positioned on tool 7700 (or equivalent). It may not hold pressure or vacuum when installed on the radiator. If so, inspect the radiator filler neck and radiator cap's top gasket for damage. Also inspect for dirt or distortion that may prevent the cap from sealing properly.

Scheme 46

Use only a mild soap and water to clean the radiator cap. Using any type of solvent may cause damage to the seal in the radiator cap.

Hold cap at eye level, right side up. The vent valve (Scheme 47) at bottom of cap should closed. A slight downward pull on the vent valve should open it. If the rubber gasket has swollen and prevents vent valve from opening, replace cap.

Hold cap at eye level, upside down. If any light can be seen between vent valve and rubber gasket, replace cap. A replacement cap must be the type designed for a coolant reserve/overflow system with a completely sealed diaphragm spring and a rubber gasket. This gasket is used to seal to radiator filler neck top surface. Use of proper cap will allow coolant return to radiator.

Scheme 47

DESCRIPTION - WATER PUMP

A centrifugal water pump circulates coolant through the water jackets, passages, intake manifold, radiator core, cooling system hoses and heater core. The pump is driven from the engine crankshaft by a single serpentine drive belt.

The water pump impeller is pressed onto the rear of a shaft that rotates in bearings pressed into the housing. The housing has two small holes to allow seepage to escape. The water pump seals are lubricated by the antifreeze in the coolant mixture. No additional lubrication is necessary.

Both heater hoses are connected to fittings on the timing chain front cover. The water pump is also mounted directly to the timing chain cover and is equipped with a non serviceable integral pulley (Scheme 48)

Scheme 48

DESCRIPTION - WATER PUMP BYPASS

The 3.7L and 4.7L engine uses an internal water/coolant bypass system. The design uses galleries in the timing chain cover to circulate coolant during engine warm-up preventing the coolant from flowing through the radiator (Scheme 49)

Scheme 49

OPERATION-WATER PUMP

A centrifugal water pump circulates coolant through the water jackets, passages, intake manifold, radiator core, cooling system hoses and heater core, this coolant absorbs the heat generated when the engine is running. The pump is driven by the engine crankshaft via a drive belt.

OPERATION - WATER PUMP BYPASS

When the thermostat is in the closed position the bypass gallery is not obstructed allowing 100% flow. When the thermostat is in the open position the pill partially covers the bypass hole, reducing the amount of bypass flow. This design allows the coolant to reach operating temperature quickly when cold, while adding extra cooling during normal temperature operation.

The water pump on 3.7L/4.7L engines is bolted directly to the engine timing chain case cover.

Scheme 50

Scheme 51

1. Disconnect the negative battery cable.
2. Drain cooling system (Refer to «REFILLING COOLING SYSTEM - ALL GAS ENGINES»(/dodge/pickup-r1500/1997-2012/remont/cooling-system-mechanical/#engine-cooling-system-diagnosis-servicing-specifications__refilling-cooling-system-all-gas) ).
3. Remove fan/viscous fan drive assembly from water pump (Scheme 50) (Refer to «REMOVAL»(/dodge/pickup-r1500/1997-2012/remont/cooling-fan/#engine-cooling-system-removal-installtion) ). Do not attempt to remove fan/viscous fan drive assembly from vehicle at this time. WARNING: CONSTANT TENSION HOSE CLAMPS ARE USED ON MOST COOLING SYSTEM HOSES. WHEN REMOVING OR INSTALLING, USE ONLY TOOLS DESIGNED FOR SERVICING THIS TYPE OF CLAMP. ALWAYS WEAR SAFETY GLASSES WHEN SERVICING CONSTANT TENSION CLAMPS. CAUTION: A number or letter is stamped into the tongue of constant tension clamps. If replacement is necessary, use only an original equipment clamp with matching number or letter and width.
4. If the water pump is being replaced, do not unbolt the fan blade assembly from the thermal viscous fan drive.
5. Remove the radiator fan (Refer to «REMOVAL»(/dodge/pickup-r1500/1997-2012/remont/cooling-fan/#engine-cooling-system-removal-installtion) ).
6. Remove accessory drive belt (Scheme 51) (Refer to «ACCESSORY DRIVE»(/dodge/pickup-r1500/1997-2012/remont/accessory-drive-belts/#accessory-drive-belt) ).
7. Remove the lower radiator hose clamp and remove the lower hose at the water pump.
8. Remove the water pump mounting bolts. CAUTION: Do not pry water pump at timing chain case/cover. The machined surfaces may be damaged resulting in leaks.
9. Remove the water pump and gasket. Discard gasket.

Clean the gasket mating surface. Use caution not to damage the gasket sealing surface.

Inspect the water pump assembly for cracks in the housing, water leaks from shaft seal, worn bearing or impeller rubbing either the pump body or timing chain case/cover.

The water pump on 3.7L/4.7L engine is bolted directly to the engine timing chain case cover.

Scheme 52

Scheme 53

1. Clean the gasket mating surfaces.
2. Using a new gasket, position water pump and install the mounting bolts. (Scheme 52) Tighten the water pump mounting bolts to 24 N.m (18 ft. lbs.) for 3.7L engines. On 4.7L engines, for appropriate bolt tightening specification, refer to «FASTENER IDENTIFICATION»(ref-285315-S01285940972008052100000).
3. Spin the water pump to be sure that the pump impeller does not rub against the timing chain case/cover.
4. Connect the radiator lower hose to the water pump.
5. Relax the tension from the belt tensioner (Scheme 51) Install the drive belt (Refer to «ACCESSORY DRIVE»(/dodge/pickup-r1500/1997-2012/remont/accessory-drive-belts/#accessory-drive-belt) ). CAUTION: When installing the serpentine accessory drive belt, the belt must be routed correctly. If not, the engine may overheat due to the water pump rotating in the wrong direction. (Scheme 53) for the correct belt routing or refer to the Belt Routing Label located in the engine compartment. The correct belt with correct length must be used.
6. Install the radiator fan (Refer to «INSTALLATION»(/dodge/pickup-r1500/1997-2012/remont/cooling-fan/#engine-cooling-system-removal-installtion) ).
7. Fill cooling system (Refer to «REFILLING COOLING SYSTEM - ALL GAS ENGINES»(/dodge/pickup-r1500/1997-2012/remont/cooling-system-mechanical/#engine-cooling-system-diagnosis-servicing-specifications__refilling-cooling-system-all-gas) ).
8. Connect the negative battery cable.
9. Start and warm the engine. Check for leaks.

1. Disconnect negative battery cable.
2. Drain coolant.
3. Remove serpentine belt.
4. Remove fan clutch assembly.
5. Remove coolant fill bottle.
6. Disconnect washer bottle wiring and hose.
7. Remove fan shroud assembly.
8. Remove A/C compressor and generator brace.
9. Remove idler pulleys.
10. Remove belt tensioner assembly.
11. Remove upper and lower radiator hoses.
12. Remove heater hoses.
13. Remove water pump mounting bolts and remove pump.

1. Install water pump and mounting bolts. Tighten mounting bolts to 24 N.m (18 ft. lbs.).
2. Install heater hoses.
3. Install upper and lower radiator hoses.
4. Install belt tensioner assembly.
5. Install idler pulleys.
6. Install A/C compressor and alternator brace. Tighten bolt and nuts to 28 N.m (21 ft. lbs.).
7. Install fan shroud assembly.
8. Connect washer bottle wiring and hose.
9. Install coolant fill bottle.
10. Install fan clutch assembly.
11. Install serpentine belt.
12. Connect negative battery cable.
13. Fill coolant.
14. Pressure test coolant system

The water pump is mounted to the front of the engine block between the automatic belt tensioner and the fan drive pulley.

The water pump impeller is pressed onto the rear of a shaft that rotates in a bearing pressed into the water pump body. The body has a small hole for ventilation. The water pump seals are lubricated by antifreeze in the coolant mixture. Additional lubrication is not necessary.

The diesel engine water pump draws coolant from the radiator outlet and circulates it through engine, heater core and back to radiator inlet. The crankshaft pulley drives the water pump with a serpentine drive belt.

DIAGNOSIS AND TESTING-WATER PUMP

A quick test to determine if pump is working is to check if heater warms properly. A defective water pump will not be able to circulate heated coolant through the long heater hose to the heater core.

Scheme 54

1. Disconnect battery negative cables.
2. Drain cooling system (Refer to «DRAINING COOLING SYSTEM 5.9L DIESEL ENGINE»(/dodge/pickup-r1500/1997-2012/remont/cooling-system-mechanical/#engine-cooling-system-diagnosis-servicing-specifications__draining-cooling-system-59l-diesel-engine) ).
3. Remove the accessory drive belt (Refer to «ACCESSORY DRIVE»(/dodge/pickup-r1500/1997-2012/remont/accessory-drive-belts/#accessory-drive-belt) ).
4. Remove water pump mounting bolts (Scheme 54)
5. Clean water pump sealing surface on cylinder block.

Clean gasket mating surfaces as necessary.

Visually inspect the water pump and replace if it has any of the following conditions

1. The body is cracked or damaged
2. Water leaks from the shaft seal. This is evident by traces of coolant below the vent hole
3. Loose or rough turning bearing.
4. Impeller rubbing the pump body

Scheme 55

1. Install new O-ring seal in groove on water pump (Scheme 55)
2. Install water pump with the weep hole facing downward. Tighten mounting bolts to 24 N.m (18 ft. lbs.) torque.
3. Install accessory drive belt (Refer to «ACCESSORY DRIVE»(/dodge/pickup-r1500/1997-2012/remont/accessory-drive-belts/#accessory-drive-belt) ).
4. Fill cooling system (Refer to «REFILLING COOLING SYSTEM 5.9L DIESEL ENGINE»(/dodge/pickup-r1500/1997-2012/remont/cooling-system-mechanical/#engine-cooling-system-diagnosis-servicing-specifications__refilling-cooling-system-59l-diesel-engine) ).
5. Connect both battery cables.
6. Start and warm the engine. Check for leaks.

See also:
• DRAINING COOLING SYSTEM - ALL GAS ENGINES
• REFILLING COOLING SYSTEM - ALL GAS ENGINES
• STEERING
• DRAINING COOLING SYSTEM 5.9L DIESEL ENGINE
• REFILLING COOLING SYSTEM 5.9L DIESEL ENGINE
• ACCESSORY DRIVE
• A/C COMPRESSOR
• DIAGNOSIS AND TESTING
• POWERTRAIN DIAGNOSTIC PROCEDURES (PART 1)
• ON-BOARD DIAGNOSTICS
• REMOVAL
• INSTALLATION