LEAK TESTING
| WARNING | If vehicle has been run recently, wait 15 minutes before removing pressure cap. Place a shop towel over the cap, and without pushing down, rotate it counterclockwise to the first stop. Allow fluids to escape through the overflow tube. When the system stops pushing coolant and steam into the coolant recovery container and pressure drops, push down on the cap and remove it completely. Squeezing the radiator inlet hose with a shop towel (to check pressure) before and after turning to the first stop is recommended. |
With engine not running, wipe the coolant filler neck sealing seat clean. The radiator should be full.
Attach Tool (special tool #7700, Tester, Cooling System) or equivalent cooling system pressure tester to the coolant filler neck. Apply 104 kPa (15 psi) pressure. If the pressure drops more than 13 kPa (2 psi) in 2 minutes inspect all points for external leaks.
All hoses, radiator and heater, should be moved while at 104 kPa (15 psi) since some leaks occur while driving due to engine movement, etc.
If there are no external leaks after the gauge dial shows a drop in pressure, detach the tester. Start engine and run the engine to normal operating temperature in order to open the thermostat and allow the coolant to expand. Reattach the tester. If the needle on the dial fluctuates, it indicates a combustion leak and is usually a head gasket leak.
| WARNING | With tool in place pressure builds up fast. Any excessive amount of pressure built up by continuous engine operation must be released to a safe pressure point. Never permit pressure to exceed 138 kpa (20 psi). |
If the needle on the dial does not fluctuate, race the engine a few times. If an abnormal amount of coolant or steam is emitted from the tailpipe, it may indicate a damaged head gasket, cracked engine block or cylinder head.
There may be internal leaks which can be determined by removing the oil dipstick. If water globules appear intermixed with the oil, it will indicate an internal leak in the engine. If there is an internal leak, the engine must be disassembled for repair.
| CONDITION | POSSIBLE CAUSE | CORRECTION |
|---|---|---|
| TEMPERATURE GAUGE READS LOW | 1. Diagnostic Trouble Code (DTC) has been set indicating a stuck open engine thermostat. | 1. Replace thermostat, if necessary. If a (DTC) has not been set, the problem may be with the temperature gauge. |
| 2. Engine Coolant Temperature Sensor. | 2. Check connector at Engine Coolant Temperature Sensor. Repair as necessary. | |
| 3. Inoperative temperature gauge. | 3. Check gauge operation. Refer to Diagnosis and Testing . | |
| 4. Coolant level low during cold ambient temperature, accompanied by poor heater performance. | 4. Check coolant level in the coolant recovery/reserve container and the radiator. Inspect the system for leaks. Repair as necessary. Refer to FLOW CHECK WARNINGS before removing pressure cap. | |
| TEMPERATURE GAUGE READS HIGH OR ENGINE COOLANT WARNING LAMP ILLUMINATES. COOLANT MAY OR MAY NOT BE LOST FROM SYSTEM. | 1. Trailer being towed, a steep hill being climbed, vehicle being operated in slow moving traffic, or engine idling during high ambient (outside) temperatures with air conditioning on. High altitudes could also cause these conditions. | 1. This may be a temporary condition and repair is not necessary. Turn off the air conditioning and drive the vehicle without any of the previous conditions. Observe the temperature gauge. The gauge should return to the normal range. If the gauge does not return to the normal range, determine the cause of the overheating and repair. |
| 2. Inoperative temperature gauge. | 2. Check gauge operation. Refer to Diagnosis and Testing . | |
| 3. Is temperature warning lamp (if equipped) illuminating unnecessarily? | 3. Check warning lamp operation. Refer to Diagnosis and Testing . | |
| 4. Coolant low in recovery/reserve bottle and radiator? | 4. Check for coolant leaks and repair as necessary. | |
| 5. Pressure cap not installed tightly. If cap is loose, boiling point of coolant will be lowered. Also refer to the following step 6. | 5. Tighten cap. | |
| 6. Poor seals at pressure cap. | 6. (a) Check condition of cap and cap seals. Refer to CAP, Radiator, Diagnosis and Testing . Replace cap if necessary. | |
| (b) Check condition of filler neck. If neck is warped or damaged, replace neck. | ||
| 7. Coolant level low in radiator, but not in coolant recovery/reserve bottle. This indicates the radiator is not drawing coolant from the coolant recovery/reserve bottle as the engine cools. As the engine cools, a vacuum is formed inside the cooling system. If the pressure cap seals are defective, or the cooling system has a leak, a vacuum cannot be formed. | 7. (a) Check condition of pressure cap and cap seals. Replace cap if necessary. | |
| (b) Check condition of filler neck. Replace if damaged. | ||
| (c) Check condition of hose from filler neck to coolant container. It should be tight at both ends without any kinks or tears. Replace hose as necessary. | ||
| (d) Check coolant recovery/reserve bottle and hose for blockage. Repair as necessary. | ||
| 8. Freeze point of coolant not correct. Mixture ratio may be too rich. | 8. Check coolant concentration. Refer to COOLANT, Diagnosis and Testing . Adjust glycol-to-water ratio as required. | |
| 9. Coolant not flowing through system. | 9. Check for coolant flow at filler neck with some coolant removed, engine warm, and thermostat open. Coolant should be observed flowing through filler neck. If flow is not observed, determine reason for lack of flow and repair as necessary. | |
| 10. Radiator air seals missing or improperly installed. | 10. Inspect air seals. Correct as necessary. | |
| 11. Radiator or A/C condenser fins are dirty or clogged. | 11. Clean obstruction from fins. | |
| 12. Radiator core is plugged or corroded. | 12. Replace or clean radiator. | |
| 13. Fuel or ignition system problems. | 13. Refer to the appropriate Powertrain Diagnostic Procedure information. | |
| 14. Dragging Brakes. | 14. Inspect brake system and repair as necessary. Refer to BASE BRAKES - SERVICE INFORMATION . | |
| 15. Bug screen or other aftermarket accessory is being used causing reduced air flow. | 15. Remove bug screen or accessory. | |
| 16. Thermostat partially or completely closed. | 16. Check thermostat operation and replace as necessary. Refer to THERMOSTAT, Diagnosis and Testing . | |
| 17. Cooling fan not operating properly. | 17. Check electric fan operation and repair as necessary. | |
| 18. Cylinder head gasket leaking. | 18. Check cylinder head gasket for leaks. Refer to Diagnosis and Testing . | |
| 19. Heater core leaking. | 19. Check heater core for leaks. | |
| TEMPERATURE GAUGE READING IS INCONSISTENT (FLUCTUATES, CYCLES OR IS ERRATIC) | 1. The gauge may cycle up and down. This is due to the cycling of the electric radiator fan. | 1. A normal condition. No correction is necessary. If gauge cycling is the hot zone, check electric fan operation and repair as necessary. |
| 2. During cold weather operation with the heater blower in the high position, the gauge reading may drop slightly. | 2. A normal condition. No correction is necessary. | |
| 3. Temperature gauge or Engine Coolant Temperature Sensor is defective or shorted. | 3. Check gauge operation. Refer to Diagnosis and Testing . | |
| 4. Gauge reading rises when vehicle is brought to a stop after heavy use (engine still running). | 4. A normal condition. No correction is necessary. The gauge should return to normal range after vehicle is driven. | |
| 5. Gauge reading high after restarting a warmed-up (hot) engine. | 5. A normal condition. No correction is necessary. The gauge should return to normal range after a few minutes of engine operation. | |
| 6. Coolant level low in radiator (air will build up in the cooling system causing the thermostat to open late). | 6. Check and correct coolant leaks. | |
| 7. Cylinder head gasket leaking allowing exhaust gas to enter cooling system. This will cause thermostat to open late. | 7. (a) Check for cylinder head gasket leaks using Tool C-3685-A Block Leak Tester or the equivalent. Repair as necessary. | |
| (b) Check for coolant in the engine oil. Inspect for white steam emitting from exhaust system. Repair as necessary. | ||
| 8. Water pump impeller loose on shaft. | 8. Check water pump and replace as necessary. | |
| 9. Air leak on the suction side of water pump allows air to build up in cooling system. This will cause the thermostat to open late. | 9. Locate leak and repair as necessary. | |
| PRESSURE CAP IS BLOWING OFF STEAM AND/OR COOLANT FLOWING INTO RECOVERY BOTTLE. TEMPERATURE GAUGE READING MAY BE ABOVE NORMAL, BUT NOT HIGH. COOLANT LEVEL MAY BE HIGH IN RECOVERY BOTTLE. | 1. Pressure relief valve in pressure cap is defective. | 1. Check condition of pressure cap and seals. Refer to CAP, Radiator, Diagnosis and Testing . Replace as necessary. |
| COOLANT LOSS TO THE GROUND WITHOUT PRESSURE CAP BLOWOFF. GAUGE IS READING HIGH OR HOT. | 1. Coolant leaks in radiator, cooling system hoses, water pump or engine. | 1. Pressure test cooling system and repair as necessary. |
| DETONATION OR PRE-IGNITION (NOT CAUSED BY IGNITION SYSTEM). GAUGE MAY OR MAY NOT BE READING HIGH. | 1. Engine overheating. | 1. Check reason for overheating and repair as necessary. |
| 2. Freeze point of coolant not correct. | 2. Check the freeze point of the coolant. Refer to COOLANT, Diagnosis and Testing . Adjust glycol-to-water ratio as required. | |
| HOSE OR HOSES COLLAPSE WHEN ENGINE IS COOLING | 1. Vacuum created in cooling system on engine cool-down is not being relieved through coolant recovery/reserve system. | 1. (a) Pressure cap relief valve stuck. Refer to CAP, Radiator, Diagnosis and Testing . Replace as necessary. |
| (b) Hose between coolant recovery/reserve bottle and outlet connector is kinked. Repair as necessary. | ||
| (c) Vent at coolant recovery/reserve bottle is plugged. Clean vent and repair as necessary. | ||
| (d) Recovery/reserve bottle is internally blocked or plugged. Check for blockage and repair as necessary. | ||
| RADIATOR FAN OPERATES ALL THE TIME | 1. Malfunctioning electrical component or circuit. | 1. Refer to appropriate Powertrain Diagnostic Procedures. Repair as necessary. |
| 2. Check for low coolant level. | 2. Repair as necessary. | |
| RADIATOR FAN WILL NOT OPERATE, GAUGE READING HIGH OR HOT | 1. Fan motor defective. | 1. Refer to appropriate Powertrain Diagnostic Procedures informatioin for operation of the scan tool. Repair as necessary. |
| 2. Fan relay, powertrain control module (PCM) or engine coolant temperature sensor defective. | 2. Refer to appropriate Powertrain Diagnostic Procedures information for operation of the scan tool. Repair as necessary. | |
| 3. Blown fuse in power distribution center (PDC). | 3. Determine cause for blown fuse and repair as necessary. | |
| NOISY FAN | 1. Fan blade loose. | 1. Replace radiator fan assembly. |
| 2. Fan blade striking a surrounding object. | 2. Locate point of fan blade contact and repair as necessary. | |
| 3. Air obstructions at radiator or A/C condenser. | 3. Remove obstructions and/or clean debris from radiator and/or A/C condenser. | |
| 4. Electric fan motor defective. | 4. Replace radiator fan assembly. | |
| INADEQUATE AIR CONDITIONER PERFORMANCE (COOLING SYSTEM SUSPECTED) | 1. Electric radiator fan not operating when A/C is on. | 1. Refer to appropriate Powertrain Diagnostic Procedures information for operation of the scan tool. Repair as necessary. |
| 2. Radiator and/or air conditioning condenser is restricted, obstructed or dirty. | 2. Remove restriction and/or clean as necessary. | |
| 3. Radiator air seals missing or improperly installed. | 3. Inspect air seals. Repair as necessary. | |
| 4. Engine is overheating (heat may be transferred from radiator to A/C condenser). High underhood temperature due to engine overheating may also transfer heat to A/C components. | 4. Correct overheating condition. Refer to Diagnosis and Testing . | |
| INADEQUATE HEATER PERFORMANCE | 1. Has a diagnostic trouble code (DTC) been set? | 1. Refer to Powertrain Diagnostic Procedures. |
| 2. Coolant level low. | 2. Check cooling system for leaks. Repair as necessary. | |
| 3. Obstructions in heater hose fittings at engine. | 3. Remove heater hoses at both ends and check for obstructions. Repair as necessary. | |
| 4. Heater hose kinked. | 4. Locate kinked area and repair as necessary. | |
| 5. Water pump is not pumping coolant to heater core. When the engine is fully warmed up, both heater hoses should be hot to the touch. | 5. Refer to PUMP, Water, Diagnosis and Testing . Repair as necessary. | |
| HEAT ODOR | 1. Various heat shields are used at certain components. One or more of these shields may be missing. | 1. Locate missing shields and replace or repair as necessary. |
| 2. Is temperature gauge reading above the normal range? | 2. Refer to the previous Temperature Gauge Reads High in these Diagnostic Charts. Repair as necessary. | |
| 3. Is cooling fan operating correctly? | 3. Repair as necessary. | |
| 4. Has undercoating been applied to any unnecessary component. | 4. Clean undercoating as necessary. | |
| 5. Engine may be running rich causing the catalytic converter to overheat. | 5. Refer to appropriate Powertrain Diagnostic Procedures information for operation of the scan tool. Repair as necessary. | |
| POOR DRIVEABILITY (THERMOSTAT POSSIBLY STUCK OPEN). GAUGE MAY BE READING LOW | 1. Has a diagnostic trouble code (DTC) been set? | 1. Refer to the Powertrain Diagnostic Procedure information for checking a DTC related to the thermostat. |
| STEAM IS COMING FROM FRONT OF VEHICLE NEAR GRILLE AREA WHEN WEATHER IS WET, ENGINE IS WARMED UP, RUNNING, AND VEHICLE IS STATIONARY. TEMPERATURE GAUGE IS IN NORMAL RANGE. | 1. During wet weather, moisture (snow, ice or rain condensation) on the radiator will evaporate when the thermostat opens. This opening allows heated water into the radiator. When the moisture contacts the hot radiator, steam may be emitted. This usually occurs in cold weather with no fan or airflow to blow it away. | 1. Occasional steam emitting from this area is normal. No repair is necessary. |
| COOLANT COLOR | 1. Coolant color is not necessarily an indication of adequate corrosion or temperature protection. Do not rely on coolant color for determining condition of coolant. | 1. Check the freeze point of the coolant. Refer to COOLANT, Diagnosis and Testing . Adjust the glycol-to-water ratio as required. |
| COOLANT LEVEL CHANGES IN COOLANT RECOVERY/RESERVE BOTTLE | 1. Level changes are to be expected as coolant volume fluctuates with engine temperature. If the level in the bottle was between the FULL HOT and ADD marks at normal engine operating temperature, the level should return to within that range after operation at elevated temperatures. | 1. A normal condition. No repair is necessary. |
Scheme 17
Note. Do not remove pressure cap for routine coolant level inspections.
The coolant recovery/reserve system provides a quick visual method for determining the coolant level without removing the radiator cap. Simply observe, with the engine idling and warmed up to normal operating temperature, that the level of the coolant in the recovery/reserve container is between the FULL HOT and ADD marks.
INSPECTION
After performing a cleaning/flush procedure, inspect all hoses, clamps and connections for deterioration and leaks. Inspect radiator and heater core for leaks.
NOISE DIAGNOSIS
Noises generated by the accessory drive belt are most noticeable at idle. Before replacing a belt to resolve a noise condition, inspect all of the accessory drive pulleys for contamination, alignment, glazing, or excessive end play.
| CONDITION | POSSIBLE CAUSES | CORRECTION |
|---|---|---|
| RIB CHUNKING (One or more ribs has separated from belt body) | 1. Foreign objects imbedded in pulley grooves. | 1. Remove foreign objects from pulley grooves. Replace belt. |
| 2. Installation damage | 2. Replace belt | |
| RIB OR BELT WEAR | 1. Pulley misaligned | 1. Align pulley(s) |
| 2. Abrasive environment | 2. Clean pulley(s). Replace belt if necessary | |
| 3. Rusted pulley(s) | 3. Clean rust from pulley(s) | |
| 4. Sharp or jagged pulley groove tips | 4. Replace pulley. Inspect belt. | |
| 5. Belt rubber deteriorated | 5. Replace belt | |
| BELT SLIPS | 1. Belt slipping because of insufficient tension | 1. Inspect/Replace tensioner if necessary |
| 2. Belt or pulley exposed to substance that has reduced friction (belt dressing, oil, ethylene glycol) | 2. Replace belt and clean pulleys | |
| 3. Driven component bearing failure (seizure) | 3. Replace component or bearing | |
| 4. Belt glazed or hardened from heat and excessive slippage | 4. Replace belt. | |
| LONGITUDINAL BELT CRACKING | 1. Belt has mistracked from pulley groove | 1. Replace belt |
| 2. Pulley groove tip has worn away rubber to tensile member | 2. Replace belt | |
| GROOVE JUMPING (Belt does not maintain correct position on pulley) | 1. Incorrect belt tension | 1. Inspect/Replace tensioner if necessary |
| 2. Pulley(s) not within design tolerance | 2. Replace pulley(s) | |
| 3. Foreign object(s) in grooves | 3. Remove foreign objects from grooves | |
| 4. Pulley misalignment | 4. Align component | |
| 5. Belt cordline is broken | 5. Replace belt | |
| BELT BROKEN (Note: Identify and correct problem before new belt is installed) | 1. Incorrect belt tension | 1. Replace Inspect/Replace tensioner if necessary |
| 2. Tensile member damaged during belt installation | 2. Replace belt | |
| 3. Severe misalignment | 3. Align pulley(s) | |
| 4. Bracket, pulley, or bearing failure | 4. Replace defective component and belt | |
| NOISE (Objectionable squeal, squeak, or rumble is heard or felt while drive belt is in operation) | 1. Incorrect belt tension | 1. Inspect/Replace tensioner if necessary |
| 2. Bearing noise | 2. Locate and repair | |
| 3. Belt misalignment | 3. Align belt/pulley(s) | |
| 4. Belt to pulley mismatch | 4. Install correct belt | |
| 5. Driven component induced vibration | 5. Locate defective driven component and repair | |
| 6. System resonant frequency induced vibration | 6. Vary belt tension within specifications | |
| TENSION SHEETING FABRIC FAILURE (Woven fabric on outside, circumference of belt has cracked or separated from body of belt) | 1. Tension sheeting contacting stationary object | 1. Correct rubbing condition |
| 2. Excessive heat causing woven fabric to age | 2. Replace belt | |
| 3. Tension sheeting splice has fractured | 3. Replace belt | |
| CORD EDGE FAILURE (Tensile member exposed at edges of belt or separated from belt body) | 1. Incorrect belt tension | 1. Inspect/Replace tensioner if necessary |
| 2. Belt contacting stationary object | 2. Replace belt | |
| 3. Pulley(s) out of tolerance | 3. Replace pulley | |
| 4. Insufficient adhesion between tensile member and rubber matrix | 4. Replace belt |
ACCESSORY DRIVE BELT DIAGNOSIS CHART
DIAGNOSIS AND TESTING - WATER PUMP
A quick flow test to determine if the water pump is working effectively is to check heater system for proper operation. A defective pump will not provide an adequate flow of heated coolant through the system.
| WARNING | DO NOT REMOVE THE COOLING SYSTEM PRESSURE CAP WITH THE SYSTEM HOT AND UNDER PRESSURE BECAUSE SERIOUS BURNS FROM COOLANT CAN OCCUR. |
Another flow test to help determine water pump operation is as follows
- Remove cooling system pressure cap.
- Remove a small amount of coolant from the system.
- Start the engine and warm up until thermostat opens.
- With the thermostat open and coolant level low, visually inspect for coolant flow. If flow is present, the water pump is pumping coolant through the system.
PRESSURE RELIEF TESTING
| WARNING | If vehicle has been run recently, wait 15 minutes before removing cap. Place a shop towel over the cap, and without pushing down, rotate it counterclockwise to the first stop. Allow fluids to escape through the overflow tube. When the system stops pushing coolant and steam into the coolant recovery container and pressure drops, push down on the cap and remove it completely. Squeezing the radiator inlet hose with a shop towel (to check pressure) before and after turning to the first stop is recommended. |
| WARNING | The warning words "do not open hot" on the pressure cap is a safety precaution. When hot, the cooling system builds up pressure. To prevent scalding or other injury, the pressure cap should not be removed while the system is hot and/or under pressure. |
The pressure cap upper gasket to filler neck seal can be checked by removing the overflow hose at the radiator filler neck overflow nipple. Attach the radiator pressure tester to the filler neck overflow nipple, and pump air into the system. The pressure cap upper gasket should relieve pressure at 69-124 kPa (10-18 psi), and hold pressure at 55 kPa (8 psi) minimum.
There is no need to remove the pressure cap at any time except for the following purposes
- Check and adjust coolant freeze point
- Refill system with new coolant
- Conducting service procedures
- Checking for leaks
Scheme 18
| 1 - OVERFLOW NIPPLE |
|---|
| 2 - MAIN SPRING |
| 3 - GASKET RETAINER |
| 4 - STAINLESS-STEEL SWIVEL TOP |
| 5 - RUBBER SEALS |
| 6 - VENT VALVE |
| 7 - THERMOSTAT HOUSING/ENGINE OUTLET CONNECTOR |
| 8 - FILLER NECK |
Hold the cap in your hand, top side up . The vent valve (6) at the bottom of the cap should not open. If the valve opens, replace the cap. If the rubber seal (5) has swollen, preventing the valve from opening, replace the cap.
Hold the cleaned cap in your hand, upside down. If any light can be seen between vent valve (6) and the rubber seal (5), replace the cap.
A replacement cap must be of the type designed for a full pressure coolant systems. This design ensures coolant return to the radiator.
DIAGNOSIS AND TESTING - COOLANT CONCENTRATION TESTING
Coolant concentration should be checked when any additional coolant was added to system or after a coolant drain, flush and refill. The coolant mixture offers optimum engine cooling and protection against corrosion when mixed to a freeze point of -37°C (-34°F) to -46°C (-50°F). The use of a hydrometer or a refractometer can be used to test coolant concentration.
A hydrometer will test the amount of glycol in a mixture by measuring the specific gravity of the mixture. The higher the concentration of ethylene glycol, the larger the number of balls that will float, and higher the freeze protection (up to a maximum of 60% by volume glycol).
A refractometer Tool (special tool #8286, Refractometer) will test the amount of glycol in a coolant mixture by measuring the amount a beam of light bends as it passes through the fluid. Refer to Special Tools .
Some coolant manufactures use other types of glycols into their coolant formulations. Propylene glycol is the most common new coolant. However, propylene glycol based coolants do not provide the same freezing protection and corrosion protection and is not recommended.
| CAUTION | Do not mix types of coolant corrosion protection will be severely reduced. |
DIAGNOSIS AND TESTING - RADIATOR FAN
(Refer to Appropriate Diagnostic Information)
DIAGNOSIS AND TESTING - ENGINE BLOCK HEATER TESTING
If unit does not operate, trouble can be in either the power cord or the heater element. Test power cord for continuity with a 110-volt voltmeter or 110-volt test light; test heater element continuity with an ohmmeter or 12-volt test light.
Scheme 19
Scheme 20
- Remove engine cover.
- Remove air cleaner inlet. 1 - RETAINING CLIP 2 - BLOCK HEATER
- Detach power cord plug from heater.
- Remove retaining clip (1). Remove block heater assembly (2).
Inspect the radiator tanks for cracks, broken or missing fittings also 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.
DIAGNOSIS AND TESTING - ENGINE COOLANT THERMOSTAT
The thermostat is operated by a wax filled chamber (pellet) which is sealed. When heated coolant reaches a predetermined temperature the wax pellet expands enough to overcome the closing spring and water pump pressure, which forces the valve to open. Coolant leakage into the pellet will cause a thermostat to fail open. Do not attempt to free up a thermostat with a screwdriver.
Thermostat diagnostics is included in Totally Integrated Power Module's (TIPM) programming for on-board diagnosis. The malfunction indicator light (MIL) will illuminate and a diagnostic trouble code (DTC) will be set when an "open too soon" condition occurs. Do not change a thermostat for lack of heater performance or temperature gauge position, unless a DTC is present. For other probable causes. Refer to Diagnosis and Testing . Thermostat failing shut is the normal long term mode of failure, and normally, only on high mileage vehicles. The temperature gauge will indicate this.
Scheme 21
| 1 - COOLANT HOSE |
|---|
| 2 - INLET HOUSING |
| 3 - BOLT |
- Partially drain THE cooling system. Refer to «Standard Procedure»(ref-463907-S41979752222012041600000) .
- Remove THE air filter housing Refer to «Standard Procedure»(ref-463907-S41979752222012041600000) .
- Disconnect the coolant hose (1) from the inlet housing (2).
- Remove inlet housing bolts (3).
- Remove the thermostat assembly, and clean the sealing surfaces.
Scheme 22
| 1 - COOLANT HOSE (REAR) |
|---|
| 2 - COOLANT ADAPTER |
| 3 - RADIATOR HOSE |
| 4 - RADIATOR HOSE (FRONT) |
- Partially drain cooling system. Refer to «Standard Procedure»(ref-463907-S41979752222012041600000) .
- Remove the air filter housing. Refer to «BODY, Air Cleaner, Removal»(ref-463897-S39248803232012041600000) or «BODY, Air Cleaner, Removal»(ref-463898-S09866072732012041600000) or «BODY, Air Cleaner, Removal»(ref-463899-S08239213792012041600000) .
- Disconnect coolant hoses (1) from rear of the coolant adapter (2).
- Remove the radiator hose (3).
- Remove the radiator hose (4) from the front of the coolant adapter (2).
- Remove the coolant adapter mounting bolts.
- Carefully slide the coolant adapter off the water pump inlet tube and remove the coolant adapter (2) and the secondary thermostat.
Scheme 23
Scheme 24
Scheme 25
Scheme 26
Scheme 27
Scheme 28
- Disconnect the negative battery cable.
- Remove the air intake duct.
- Siphon the power steering fluid from the reservoir.
- Remove the fan module assembly. Refer to «FAN, Cooling, Removal»(ref-463907-S14236962252012041600000) .
- Remove the front upper air charge hose (1).
- Remove the front lower air charge hose (2) to the EGR throttle control housing.
- Remove the brake booster vacuum line support bracket (1).
- Disconnect the electrical connector to the EGR throttle control motor and charge air temperature sensor (1).
- Loosen the lower hose clamp from the thermostat housing to the combination water/power steering pump.
- Raise vehicle.
- Remove main drive belt (3). Refer to «BELT, Serpentine, Removal»(ref-463907-S04169480002012041600000) .
- Remove the water/power steering pump assembly. Refer to «PUMP, Water, Removal»(ref-463907-S26682395342012041600000) or «PUMP, Water, Afterrun, Removal»(ref-463907-S41514956892012041600000) .
- Remove the brake booster vacuum line check valve (1) from the vacuum pump.
- Remove the four mounting screws (2) from the EGR throttle control (3) to the mixing tank.
- Position the inlet nozzle (1) aside, to be removed from the top side of vehicle.
- Remove the EGR throttle control assembly (3). NOTE: The thermostat must be replaced with the housing. Trying to remove the thermostat from the housing will damage the housing and the thermostat.
- Remove the lower thermostat housing mounting bolt (2).
- Lower vehicle.
- Remove the intake nozzle.
- Disconnect the thermostat heater connector (1).
- Remove the upper thermostat housing bolt (2).
- Remove the thermostat housing by moving the housing in a side to side motion.
Scheme 29
Note. Turbocharged engine use a orifice plate in place of a secondary thermostat.
- Inspect the water pump inlet tube O-rings for damage before installing the tube in the coolant adapter. Replace O-ring as necessary.
- Position the orifice plate and coolant adapter onto the cylinder head water pump tube.
- Install the coolant adapter mounting bolts. Tighten the bolts to 18 N.m (159 in. lbs.).
- Install the coolant hose (8) onto the coolant adapter (6).
- Install the coolant hose (7) onto the coolant adapter (6).
- Install the coolant hose (4) onto the coolant adapter (6).
- Install the coolant hose (1) onto the thermostat housing (2).
- Connect the ECT sensor electrical connector (3).
- Install the air filter housing Refer to «BODY, Air Cleaner, Installation»(ref-463897-S08564638532012041600000) or «BODY, Air Cleaner, Installation»(ref-463898-S05044287472012041600000) or «BODY, Air Cleaner, Installation»(ref-463899-S26434350682012041600000) .
- Fill the cooling system. Refer to «Standard Procedure»(ref-463907-S41979752222012041600000) .
Inspect all hoses, tubes, clamps and connections for leaks, cracks, or damage. Replace as necessary. Use only approved transmission oil cooler hoses that are molded to fit the space available.
Inspect external coolers for leaks, loose mounts, or damage. Replace as necessary.