SECTION 1D2
ENGINE COOLING - FAM II 2.4D
Caution : Disconnect the negative battery cable before removing or installing any electrical unit or when a tool or equipment could easily come in contact with exposed electrical terminals. Disconnecting this cable will help to prevent personal injury and damage to the vehicle. The ignition must also be in LOCK unless otherwise noted.
SPECIFICATIONS
Cooling System Specifications
Application | Description | Unit | Standard |
Cooling System | Cooling Type | - | Pressurized |
Coolant | Type | - | Dexcool/Silicate Based Coolant |
Capacity | L (qt) | 9 (9.5) |
Thermostat | Type | - | Wax Pellet |
Temperature (Opened Initially) | °C (°F) | 87°C (189°F) |
Temperature (Completely Opened) | °C (°F) | 102°C (226°F) |
Temperature (Completely Closed) | °C (°F) | 86°C (187°F) |
Cooling Fan | Type | - | Electrical Dual Fan |
Number of Blade | EA | 5(Main) / 7(Aux) |
Diameter | mm (in.) | Main : 340 (13.4) / Aux : 320 (12.6) |
ON Temperature at Low Speed | °C (°F) | 96 (204.8) |
OFF Temperature at Low Speed | °C (°F) | 93 (199.4) |
ON Temperature at High Speed | °C (°F) | 100 (212) |
OFF Temperature at High Speed | °C (°F) | 97 (206.6) |
Surge Tank | Open Pressure of the Pressure Valve | kPa | 140 |
Open Pressure of the Vacuum Valve | kPa | 10 |
Water Pump | Type | - | Centrifugal |
Impeller Diameter | mm (in.) | 55 (2.17) |
Number of Impeller Blade | EA | 6 |
Radiator | Type | - | Cross Flow |
Core Width | mm (in.) | 673 (26.50) |
Core Height | mm (in.) | 511 (20.12) |
Core Depth | mm (in.) | 27 (1.063) |
Minimum Cooling Capacity | Kcal/h | 83,000 |
Coolant Temperature Sensor (CTS) | Type | - | NTC |
Signal Voltage (at normal engine temp.) | V | 1.0~2.0 |
Resistance (at –40°C) | kΩ | 100.78 |
Resistance (at –20°C) | kΩ | 24.75~33.26 |
Resistance (at 0°C) | kΩ | 8.38~10.61 |
Resistance (at 40°C) | kΩ | 1.37~1.56 |
Resistance (at 80°C) | kΩ | 0.32~0.35 |
Resistance (at 120°C) | kΩ | 0.093~0.107 |
Fastener Tightening Specifications
Application | N•m | Lb-Ft | Lb-In |
Fan Assembly Mounting Bolts | 4 | - | 35 |
Fan Blade Retaining Nut | 5.6 | - | 50 |
Fan Motor Retaining Screws | 3.5 | - | 31 |
Radiator Upper Left and Right Bracket Retaining Bolts | 20 | 15 | - |
Surge Tank Mounting Bolt and Nut | 8 | - | 71 |
Thermostat Housing Mounting Bolts | 15 | 11 | - |
Water Pump Mounting Bolts | 25 | 18 | - |
COMPONENT LOCATOR
Radiator and Fan
- Radiator Upper Bracket
- Lower Radiator Bumper
- Radiator
- Main Cooling Fan
- Auxiliary Cooling Fan
- Main Cooling Fan Motor
- Auxiliary Cooling Fan Motor
- Cooling Fan Shroud Assembly
- Coolant Drain Cock
Water Pump and Thermostat
- Seal Ring
- Thermostat
- Thermostat Housing
- Thermostat Housing Mounting Bolt
- Water Pump Mounting Bolt
- Water Pump
- Seal Ring
DIAGNOSIS
Thermostat Test
- Remove the thermostat from the vehicle. Refer to "Thermostat" in this section.
- Make sure the valve spring is tight when the thermostat is fully closed. If the spring is not tight, replace the thermostat.
- Suspend the thermostat and a thermometer in a pan of 50/50 mixture of Dex-cool/Silicate Based Coolant and water. Do not let the thermostat or the thermometer rest on the bottom of the pan because the uneven concentration of heat on the bottom could result in inaccurate temperature measurements.
- Heat the pan on a burner.
- Use the thermometer to measure the temperature of the heated solution.
- The thermostat should begin to open at 87°C (189°F) and it should be fully open at 102°C (216°F). If it does not open at these temperatures, replace the thermostat.
Cooling System Diagnosis
Engine Overheats
Checks | Action |
Check for a loss of the coolant. | Add the coolant. |
Check for a weak coolant solution. | Confirm that the coolant solution is a 50/50 mixture of ethylene glycol and water. |
Check the front of the radiator for any dirt, any leaves, or any insects. | Clean the front of the radiator. |
Check for leakage from the hoses, the water pump, the heater, the thermostat housing, the radiator, the core plugs, or the head gasket. | Replace any damaged components. |
Check for a faulty thermostat. | Replace a damaged thermostat. |
Check for retarded ignition timing. | Perform an ECM code diagnosis. Confirm the integrity of the timing belt. |
Check for an improperly operating electric cooling fan. | Replace the electric cooling fan. |
Check for radiator hoses that are plugged or rotted. | Replace any damaged radiator hoses. |
Check for a faulty water pump. | Replace a faulty water pump. |
Check for a faulty surge tank cap. | Replace a faulty surge tank cap. |
Check for a cylinder head or an engine block that is cracked or plugged. | Repair the damaged cylinder head or the damaged engine block. |
Loss of Coolant
Checks | Action |
Check for a leak in the radiator. | Replace a damaged radiator. |
Check for a leak in the following locations: | Replace the following parts, as needed: |
Check for loose or damaged radiator hoses, heater hoses, and connections. | Reseat the hoses. Replace the hoses or the clamps. |
Check for leaks in the water pump seal. | Replace the water pump seal. |
Check for leaks in the water pump gasket. | Replace the water pump gasket. |
Check for an improper cylinder head torque. | Tighten the cylinder head bolts to specifications. Replace the cylinder head gasket, if needed. |
Check for leaks in the following locations: - Intake manifold.
- Cylinder head gasket.
- Cylinder block plug.
- Heater core.
- Radiator drain plug.
| Repair or replace any components, as needed, to correct the leak. |
Engine Fails to Reach Normal Operating Temperature or Cool Air from the Heater
Checks | Action |
Check to determine if the thermostat is stuck open or is the wrong type of thermostat. | Install a new thermostat of the correct type and heat range. |
Check the coolant level to determine if it is below the MIN mark on the surge tank. | Add sufficient coolant to raise the fluid to the specified mark on the surge tank. |
MAINTENANCE AND REPAIR
ON-VEHICLE SERVICE
Draining and Refilling the Cooling System
Important : The cooling sysem in the vehicle is designed to use either Dex-cool coolant, which is red in color, or silicate based coolant, which is blue. These two types of coolant are not compatible with each other and should never be mixed. Even if the cooling system has been completely drained before a refill, do not switch types of coolant.
Caution : Do not remove the surge tank cap while the engine and the radiator are hot. Scalding fluid and steam may be blown out high pressure.
- Place a pan below the vehicle to catch the draining coolant.
- Remove the surge tank cap.
- Unplug the drain cock.
Caution : Dispose of the used coolant to a used coolant holding tank to be picked up with the used oil for disposal. Never pour the used coolant down the drain.
- Catch the escaping fluid in a drain pan.
- Remove all sludge and dirt from inside of the surge tank. Refer to "Surge Tank" in this section.
- Plug the drain cock.
- Add the clean water to the surge tank.
- Fill the tank slowly so that the upper reservoir hose remains above the water line. This allows the air inside the cooling system to escape.
- Start the engine.
- Run the engine until the thermostat opens. You can tell the thermostat is open when both radiator hoses are hot to the touch.
- Stop the engine.
- Repeat steps 1 through 9 until the drained water is clear and free of coolant and rust.
Notice : Never use an antifreeze mixture more concentrated than 60% antifreeze to 40% water. The solution freezing point increases above this concentration.
- Fill the cooling system through the surge tank with a mixture of Dex-cool and water. The mixture must be at least 50% antifreeze, but not more than 60% antifreeze.
- Fill the surge tank to the specified MAX fill mark on the outside of the tank.
Thermostat
Removal Procedure
Caution : To prevent personal injury, do not remove the surge tank cap while the engine and the radiator are hot because the heat caused the system to remain under pressure. Scalding fluid and steam may be blown out high pressure.
- Drain the coolant. Refer to "Draining and Refilling the Cooling System" in this section.
- Loosen the hose clamp on the upper radiator hose at the thermostat housing.
- Disconnect the upper radiator hose from the thermostat housing.
- Remove the mounting bolts that hold the thermostat housing to the cylinder head.
- Remove the thermostat housing from the cylinder head.
- Remove the seal ring from the thermostat housing.
- Remove the thermostat from the thermostat housing by pressing the thermostat mounting flange downward and then rotating the flange clockwise.
- Inspect the valve seat for foreign matter that could prevent the valve from sealing properly.
- Inspect the thermostat for proper operation. Refer to "Thermostat Test" in this section.
- Clean the thermostat housing and the cylinder head mating surfaces.
Installation Procedure
- Install the thermostat into the thermostat housing by pressing the thermostat mounting flange downward and then rotating the flange counterclockwise. Rotate the thermostat mounting flange until it is seated in the thermostat housing recesses.
- Install a new seal ring into the recess in the thermostat housing.
- Install the thermostat housing to the cylinder head.
- Secure the thermostat housing to the cylinder head with the mounting bolts.
Tighten
Tighten the thermostat housing mounting bolts to 15 N•m (11 lb-ft).
- Connect the upper radiator hose to the thermostat housing.
- Secure the upper radiator hose to the thermostat housing with a hose clamp.
- Refill the engine cooling system. Refer to "Draining and Refilling the Cooling System" in this section.
Water Pump
Removal Procedure
- Drain the engine cooling system to a level below the thermostat housing. Refer to "Draining and Refilling the Cooling System" in this section.
- Remove the timing belt. Refer to Section 1C1, Engine Mechanical - FAM II 2.4D.
- Remove the timing belt automatic tensioner.
- Remove the water pump mounting bolts.
- Remove the water pump from the engine block.
- Remove the ring seal from the water pump.
Inspection Cleaning Procedure
- Inspect the water pump body for cracks and leaks.
- Inspect the water pump bearing for play or abnormal noise.
- Inspect the water pump pulley for excessive wear. If the water pump is defective, replace the water pump as a unit.
- Clean the mating surfaces of the water pump and the engine block.
Installation Procedure
- Install a new ring seal to the water pump.
- Install the water pump to the engine block with the flange aligned with the recess of the rear timing belt cover.
- Secure the water pump to the engine block with the mounting bolts.
Tighten
Tighten the water pump mounting bolts to 25 N•m (18 lb-ft).
- Install the timing belt automatic tensioner to the oil pump with the flange inserted into the recess of the oil pump.
- Install the timing belt automatic tensioner bolts. Do not fully tighten the bolt at this time.
- Install the timing belt. Refer to Section 1C1, Engine Mechanical - FAM II 2.4D.
- Refill the engine cooling system. Refer to "Draining and Refilling the Cooling System" in this section.
Electric Cooling Fan Assembly
Removal Procedure
- Disconnect the negative battery cable.
- Remove the engine cover and the engine cover bracket.
- Remove the battery. Refer to Section 1E2, Engine Electrical – FAM II 2.4D.
- Remove the air cleaner assembly. Refer to Section 1C1, Engine Mechanical – FAM II 2.4D.
- Disconnect the both cooling fan electrical connectors and the A/C pressure sensor connector.
- Remove the cooling fan shroud mounting bolts.
- Remove the power steering fluid supply hose and pipe retaining bracket and move it away from the cooling fan assembly. Refer to Section 6A, Power Steering System.
- Lift the fan shroud assembly upward and remove the cooling fan assembly from the vehicle.
- Remove the both main and auxiliary fan blades from the fan shroud assembly by removing the nut at the center of the fan hubs.
- Remove the both fan motor retaining screws.
- Remove the both fan motors from the shroud.
Installation Procedure
Caution : If a fan assembly is bent or damaged in any way, no attempt should be made to repair or reuse the damaged part. A bent or damaged fan assembly must be replaced with a new fan assembly. It is essential to remain the fan assemblies in proper balance. A fan assembly that is not in proper balance can fail and fly apart during use, creating extreme danger. Proper balance cannot be assured on a fan assembly that has been bent or damaged.
- Install the both fan motors to the shroud.
- Secure the motors to the shroud with the retaining screws.
Tighten
Tighten the fan motor retaining screws to 3.5 N•m (31 lb-in.).
- Install the fan blades to the fan shroud assembly with the nuts in the center of the fan hub.
Tighten
Tighten the fan blades retaining nuts to 5.6 N•m (50 lb-in.).
- Install the cooling fan assembly to the radiator.
Important : Be sure to slip the tab at the bottom edge of the shroud into the retaining clip at the radiator.
- Secure the cooling fan assembly to the top of the radiator with the mounting bolts.
Tighten
Tighten the cooling fan assembly mounting bolts to 4 N•m (35 lb-in.).
- Connect the cooling fan electrical connectors and the A/C pressure sensor connector.
- Install the power steering fluid supply hose and pipe retaining bracket bolt and move it away from the cooling fan assembly. Refer to Section 6A, Power Steering System.
- Install the air cleaner assembly. Refer to Section 1C1, Engine Mechanical – FAM II 2.4D.
- Install the battery. Refer to Section 1E2, Engine Electrical – FAM II 2.4D.
- Install the engine cover and the engine cover bracket.
- Connect the negative battery cable.
Surge Tank
Removal Procedure
Caution : To prevent personal injury, do not remove the surge tank cap while the engine and the radiator are hot because the heat caused the system to remain under pressure. Scalding fluid and steam may be blown out high pressure.
- Drain the engine coolant to below the level of the surge tank.
Note : Do not drain the power steering fluid at this stage.
- Remove the power steering fluid reservoir retaining bolts and move the reservoir away from the surge tank. Refer to Section 6A, Power Steering System.
- Loosen the return hose clamp and disconnect the return hose from the top of the surge tank.
- Loosen the throttle body hose clamp and disconnect the throttle body hose from the top of the surge tank.
- Loosen the feed hose clamp and disconnect the feed hose from the bottom of the surge tank.
- Remove the surge tank attaching bolt and nut.
- Remove the surge tank.
- Clean the inside and the outside of the surge tank and the surge tank cap with soap and water.
- Rinse the surge tank and the cap thoroughly.
Installation Procedure
- Install the surge tank.
- Secure the surge tank with the attaching bolt and nut.
Tighten
Tighten the surge tank retaining bolt and nut to 8 N•m (71 lb-in.).
- Connect the return hose and the throttle body hose to the top of the surge tank.
- Connect the feed hose to the bottom of the surge tank.
- Secure the return hose, throttle body hose and the feed hose to the surge tank with the hose clamps.
- Fill the surge tank with the coolant to the center ridge or the MAX mark.
Radiator
Removal Procedure
- Disconnect the negative battery cable.
- Drain the engine cooling system. Refer to "Draining and Refilling the Cooling System" in this section.
- Remove the engine cover and the engine cover bracket.
- Disconnect the both cooling fan electrical connectors and the A/C pressure sensor connector.
- Remove the radiator grill upper guide. Refer to Section 9R, Body Front End.
- Remove the A/C condenser upper and lower bracket from the radiator. Refer to Section 7B, Manual Control Heating, Ventilation, and Air Conditioning System.
- Hang the A/C condenser to prevent it from falling down.
- Remove the radiator upper bracket retaining bolts.
- Remove the radiator upper brackets.
- Disconnect the transaxle cooler pipes from the lower radiator tank, if equipped.
- Loosen the upper radiator hose clamp and then disconnect the upper radiator hose from the radiator.
- Loosen the lower radiator hose clamp and then disconnect the lower radiator hose from the radiator.
- Loosen the clamp and disconnect the coolant return hose.
- Lift and carefully support the vehicle.
- Remove the condenser, radiator, fan module (CRFM) assembly support bracket mounting upper bolts.
- Remove the CRFM assembly support bracket through bolts and nuts.
- Remove the both CRFM assembly support brackets.
Caution : Do not to damage the radiator fins for the proper operation of the cooling system.
- Carefully lower the radiator and fan assembly from the vehicle.
- Remove the radiator.
- Remove the cooling fan assembly from the radiator if necessary.
Cleaning
Caution : NEVER spray water on a hot radiator. The resulting steam could cause personal injury.
Notice : The radiator fins are necessary for good heat transfer. Do not brush the fins. This may cause damage to the fins, reducing heat transfer.
Important : Remove bugs, leaves, dirt and other debris by blowing compressed air through the engine side of the radiator.
Some conditions may require the use of warm water and a mild detergent.
- Clean the radiator cooling fins.
- Straighten any damaged cooling fins.
Installation Procedure
Caution : Do not to damage the radiator fins for the proper operation of the cooling system.
- Install the cooling fan assembly if necessary.
- Install the radiator.
- Carefully lift the radiator into the position previously removed.
- Install the both CRFM assembly support brackets.
- Install the CRFM assembly support bracket through bolts and nuts.
Tighten
Tighten the CRFM assembly support bracket through bolts and nuts to 50 N•m (37 lb-ft).
- Install the CRFM assembly support bracket mounting upper bolts.
Tighten
Tighten the CRFM assembly support bracket mounting upper bolts to 50 N•m (37 lb-ft).
- Connect the lower radiator hose to the radiator and then secure the clamp.
- Connect the upper radiator hose to the radiator and then secure the clamp.
- Connect the transaxle cooler pipes to the radiator, if equipped.
- Connect the coolant return hose.
- Install the A/C condenser to the radiator.
- Install the radiator upper brackets.
Tighten
Tighten the radiator upper bracket retaining bolts to 20 N•m (15 lb-ft).
- Install the radiator grill upper guide. Refer to Section 9R, Body Front End.
- Install the engine cover bracket and then the engine cover.
- Fill the engine cooling system. Refer to "Draining and Refilling the Cooling System" in this section.
- Connect the negative battery.
GENERAL DESCRIPTION AND SYSTEM OPERATION
General Description
The cooling system maintains the engine temperature at an efficient level during all engine operating conditions.
When the engine is cold, the cooling system cools the engine slowly or not at all. This slow cooling of the engine allows the engine to warm up quickly.
The cooling system includes a radiator and recovery subsystem, cooling fans, a thermostat and housing, a water pump, and a water pump drive belt. The timing belt drives the water pump.
All components must function properly in order for the cooling system to operate. The water pump draws the coolant from the radiator. The coolant then circulates through water jackets in the engine block, the intake manifold, and the cylinder head. When the coolant reaches the operating temperature of the thermostat, the thermostat opens. The coolant then goes back to the radiator where it cools.This system directs some coolant through the hoses to the heater core. This provides for heating and defrosting. The surge tank is connected to the radiator to recover the coolant displaced by expansion from the high temperatures.
The surge tank maintains the correct coolant level.
The cooling system for this vehicle has no radiator cap or filler neck. The coolant is added to the cooling system through the surge tank.
Radiator
This vehicle has a lightweight tube–and–fin aluminum radiator. Plastic tanks are mounted on the right and the left sides of the radiator core.
On vehicles equipped with automatic transaxles, the transaxle fluid cooler lines run through the left radiator tank. A radiator drain cock is on this radiator. To drain the cooling system, open the drain cock.
Surge Tank
The surge tank is a transparent plastic reservoir, similar to the windshield washer reservoir.
The surge tank is connected to the radiator by a hose and to the engine cooling system by another hose. As the vehicle is driven, the engine coolant heats and expands. The portion of the engine coolant displaced by this expansion flows from the radiator and the engine into the surge tank. The air trapped in the radiator and the engine is degassed into the surge tank.
When the engine stops, the engine coolant cools and contracts. The displaced engine coolant is then drawn back into the radiator and the engine. This keeps the radiator filled with the coolant to the desired level at all times and increases the cooling efficiency.
Maintain the coolant level between the MIN and the MAX marks on the surge tank when the system is cold.
Water Pump
The belt–driven centrifugal water pump consists of an impeller, a drive shaft, and a belt pulley. The water pump is mounted on the front of the transverse–mounted engine, and is driven by the timing belt.
The impeller is supported by a completely sealed bearing. The water pump is serviced as an assembly and, therefore, cannot be disassembled.
Thermostat
A wax pellet–type thermostat controls the flow of the engine coolant through the engine cooling system. The thermostat is mounted in the thermostat housing to the front of the cylinder head.
The thermostat stops the flow of the engine coolant from the engine to the radiator in order to provide faster warm–up, and to regulate the coolant temperature. The thermostat remains closed while the engine coolant is cold, preventing circulation of the engine coolant through the radiator. At this point, the engine coolant is allowed to circulate only throughout the heater core to warm it quickly and evenly.
As the engine warms, the thermostat opens. This allows the engine coolant to flow through the radiator, where the heat is dissipated through the radiator. This opening and closing of the thermostat permits enough engine coolant to enter the radiator to keep the engine within proper engine temperature operating limits.
The wax pellet in the thermostat is hermetically sealed in a metal case. The wax element of the thermostat expands when it is heated and contracts when it is cooled.
As the vehicle is driven and the engine warms, the engine coolant temperature increases. When the engine coolant reaches a specified temperature, the wax pellet element in the thermostat expands and exerts pressure against the metal case, forcing the valve open. This allows the engine coolant to flow through the engine cooling system and cool the engine. As the wax pellet cools, the contraction allows a spring to close the valve.
The thermostat begins to open at 87°C (189°F) and is fully opened at 102°C (216°F). The thermostat is closed at 86°C (187°F).
Electric Cooling Fan
Caution : Keep hands, tools, and clothing away from the engine cooling fans to help prevent personal injury. This fan is electric and can turn ON whether or not the engine is running.
Caution : If a fan blade is bent or damaged in any way, no attempt should be made to repair or reuse the damaged part. A bent or damaged fan assembly should always be replaced with a new one. Failure to do so can result in personal injury.
The cooling fans are mounted behind the radiator in the engine compartment. Cooling system on this vehicle has two cooling fans – the main fan and the auxiliary fan. The electric cooling fans increase the flow of air across the radiator fins and across the condenser on air condition (A/C) equipped vehicles. This helps to speed cooling when the vehicle is at idle or moving at low speeds.
A vehicle equipped with the A/C or Non-A/C has two fans on the one shroud. The main fan size is 340 mm (13.4 inches) in diameter with five blades, and the auxiliary fan size is 320 mm (12.6 inches) in diameter with seven blades to aid the airflow through the radiator and the condenser. Two electric fan motors attached to the center of each fan on the fan shroud assembly drive the both fans.
A/C OFF or Non-A/C Model
- The cooling fans are actuated by the electronic control module (ECM) using the serial/parallel cooling fan relay.
- The ECM will turn the cooling fans on at low speed when the coolant temperature reaches 96°C (205°F) and at high speed when the coolant temperature reaches 100°C (212°F).
- The ECM will change the cooling fans from high speed to low speed at 94°C (201°F) and will turn the cooling fans off at 90°C (194°F).
A/C ON
- The ECM will turn the cooling fans on at low speed when the A/C system is on. The ECM will change to high speed when the coolant temperature reaches 118°C (244°F) or the high side A/C pressure reaches 1760 kPa (255 psi).
- The cooling fans will return to low speed when the coolant temperature reaches 115°C (239°F) and the high side A/C pressure reaches 1347 kPa (195 psi).
