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Cooling System Acura RDX I

Cooling System (mechanical) 49 illustrations ~2361 words

Scheme 1

Scheme 1: Component Location Index
Scheme 1: Component Location Index

Scheme 2

Scheme 2: Radiator Cap Test
Scheme 2: Radiator Cap Test
  1. Remove the radiator cap (A). Wet the seal with engine coolant, then install it on a commercially available pressure tester (B).
  2. Apply a pressure of 93-123 kPa (0.95-1.25 kgf/cm 2 , 14-18 psi).
  3. Check for a drop in pressure.
  4. If the pressure drops, replace the cap.

Scheme 3

Scheme 3: Radiator Test
Scheme 3: Radiator Test
  1. Wait until the engine is cool, then carefully remove the radiator cap, and fill the radiator with engine coolant to the top of the filler neck.
  2. Attach a commercially available pressure tester (A) to the radiator, and apply a pressure of 93-123 kPa (0.95-1.25 kgf/cm 2 , 14-18 psi).
  3. Inspect for engine coolant leaks, and a drop in pressure.
  4. Remove the tester, then reinstall the radiator cap.

Scheme 4

Scheme 4: Fan Motor Test
Scheme 4: Fan Motor Test
  1. Disconnect the 2P connectors from the radiator fan motor and condenser fan motor.
  2. Test the motor by connecting battery power to terminal No. 2 and ground to terminal No. 1.
  3. If the motor fails to run or does not run smoothly, replace it «FAN, FAN MOTOR, AND SHROUD REMOVAL AND INSTALLATION»(/acura/rdx/i-2006-2009/remont/cooling-system-mechanical/#cooling-system) .

Thermostat Test

Replace the thermostat if it is stuck open at room temperature.

To test a closed thermostat

Scheme 5

Scheme 5: Thermostat Test
Scheme 5: Thermostat Test
  1. Suspend the thermostat (A) in a container of water. Do not let the thermometer (B) touch the bottom of the hot container.
  2. Heat the water and check the temperature with a thermometer. Check the temperature when the thermostat first opens, then check the temperature when the thermostat is fully open.
  3. Measure the lift height of the thermostat when it is fully open. If the thermostat is not within the specification, replace it. Standard Thermostat Lift Height: Above 8.0 mm (0.31 in.) Starts Opening: 169-176°F (76-80°C) Fully Open: 194°F (90°C)

Water Pump Inspection

Special Tools Required

A/C clutch holder, Robin air 10204 or Kent-Moore J37872, or Honda Tool and Equipment KMT-J33939, commercially available

Scheme 6

Scheme 6: Water Pump Inspection
Scheme 6: Water Pump Inspection

Scheme 7

Scheme 7
Scheme 7
  1. Remove the splash shield (see step 25 under «ENGINE REMOVAL»(/acura/rdx/i-2006-2009/remont/mechanical/#engine-removal-and-installation) ).
  2. Remove the drive belt (see «DRIVE BELT REMOVAL/INSTALLATION»(/acura/rdx/i-2006-2009/remont/charging-system/#charging-system__drive-belt-removalinstallation) ).
  3. Hold the water pump pulley using the A/C clutch holder (A) and remove the water pump pulley mounting bolts (B), then remove the water pump pulley.
  4. Turn the water pump counterclockwise, and make sure that it turns freely. If it doesn't, replace the water pump (see «WATER PUMP REPLACEMENT»(/acura/rdx/i-2006-2009/remont/cooling-system-mechanical/#cooling-system__water-pump-replacement) ). NOTE: When you check the water pump, you may see a small amount of "weeping" from the bleed holes (A). This is normal.
  5. Install the water pump pulley.
  6. Install the drive belt (see «DRIVE BELT REMOVAL/INSTALLATION»(/acura/rdx/i-2006-2009/remont/charging-system/#charging-system__drive-belt-removalinstallation) ).
  7. Install the splash shield (see step 30 under «ENGINE INSTALLATION»(/acura/rdx/i-2006-2009/remont/mechanical/#engine-removal-and-installation__engine-installation) ).

Water Pump Replacement

Special Tools Required

A/C clutch holder, Robin air 10204 or Kent-Moore J37872, or Honda Tool and Equipment KMT-J33939, commercially available

Scheme 8

Scheme 8: Water Pump Replacement
Scheme 8: Water Pump Replacement

Scheme 9

Scheme 9
Scheme 9
  1. Drain the engine coolant (see «COOLANT CHECK»(/acura/rdx/i-2006-2009/remont/cooling-system-mechanical/#cooling-system) ).
  2. Remove the splash shield (see step 25 under «ENGINE REMOVAL»(/acura/rdx/i-2006-2009/remont/mechanical/#engine-removal-and-installation) ).
  3. Remove the drive belt (see «DRIVE BELT REMOVAL/INSTALLATION»(/acura/rdx/i-2006-2009/remont/charging-system/#charging-system__drive-belt-removalinstallation) ).
  4. Hold the water pump pulley using the A/C clutch holder (A), and remove the water pump pulley mounting bolts (B), then remove the water pump pulley.
  5. Remove the water pump (A) by removing the six bolts.
  6. Inspect, and clean the O-ring groove and the mating surface of the engine block.
  7. Install the water pump with a new O-ring (B) in the reverse order of removal.
  8. Clean up any spilled engine coolant.
  9. Install the water pump pulley.
  10. Install the drive belt (see «DRIVE BELT REMOVAL/INSTALLATION»(/acura/rdx/i-2006-2009/remont/charging-system/#charging-system__drive-belt-removalinstallation) ).
  11. Install the splash shield (see step 30 under «ENGINE INSTALLATION»(/acura/rdx/i-2006-2009/remont/mechanical/#engine-removal-and-installation__engine-installation) ).
  12. Refill the radiator with engine coolant, then bleed the air from the cooling system with the heater valve open (see step 6 ).

Scheme 10

Scheme 10: Coolant Check
Scheme 10: Coolant Check
  1. Look at the coolant level in the coolant reservoir. Make sure it is between the MAX mark (A) and MIN mark (B).
  2. If the coolant level in the coolant reservoir is at or below the MIN mark, add coolant to bring it up to the MAX mark, then inspect the cooling system for leaks.

Scheme 11

Scheme 11: Coolant Replacement
Scheme 11: Coolant Replacement

Scheme 12

Scheme 12
Scheme 12

Scheme 13

Scheme 13
Scheme 13
  1. Start the engine. Set the heater temperature control dial to maximum heat, then turn off the ignition switch. Make sure the engine and radiator are cool to the touch.
  2. Remove the radiator cap.
  3. Loosen the drain plug (A) and drain the coolant.
  4. After the coolant has drained, tighten the radiator drain plug.
  5. Remove the coolant reservoir and drain the coolant. Reinstall the coolant reservoir.
  6. Fill the coolant reservoir to the MAX mark (A) with Acura Long Life Antifreeze/Coolant Type 2 (P/N OL999-9011A).
  7. Pour Acura Long Life Antifreeze/Coolant Type 2 (P/N OL999-9011A) into the radiator up to the base of the filler neck. NOTE: Always use Acura Long Life Antifreeze/Coolant Type 2 (P/N OL999-9011A). Using a non-Acura coolant can result in corrosion, causing the cooling system to malfunction or fail. Acura Long Life Antifreeze/Coolant Type 2 is a mixture of 50% antifreeze and 50% water. Do not add water. Engine Coolant Capacities (Including the reserve tank capacity of 0.7 L (0.18 US gal)) At Coolant Change: 7.0 L (1.85 US gal) After Engine Overhaul: 8.4 L (2.22 US gal)
  8. Loosely install the radiator cap.
  9. Start the engine, and let it run until it warms up (the radiator fan comes on at least twice).
  10. Turn off the engine. Check the level in the radiator and add Acura Long Life Antifreeze/Coolant Type 2 if needed. NOTE: Removing the radiator cap while the engine is hot can cause the coolant to spray out. Always let the engine and radiator cool before removing the cap.
  11. Put the radiator cap on tightly, then run the engine again and check for leaks.
  12. Clean up any spilled engine coolant.
  13. Connect the Honda Diagnostic System (HDS) to the data link connector (DLC).(see step 2 on «GENERAL TROUBLESHOOTING INFORMATION»(/acura/rdx/i-2006-2009/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems)
  14. Make sure the HDS communicates with the vehicle and the powertrain control module (PCM). If it does not communicate, troubleshoot the DLC circuit(see «DLC CIRCUIT TROUBLESHOOTING»(/acura/rdx/i-2006-2009/remont/testing-diagnostics/#pgm-fi-system__dlc-circuit-troubleshooting) .
  15. Turn the ignition switch to ON (II).
  16. Select BODY ELECTRICAL with the HDS.
  17. Select ADJUSTMENT in the GAUGE MENU with the HDS.
  18. Select RESET in the MAINTENANCE MINDER with HDS.
  19. Select MAINTENANCE SUB ITEM 5 RESET with HDS.

Scheme 14

Scheme 14: Thermostat Replacement
Scheme 14: Thermostat Replacement
  1. Drain the engine coolant (see «COOLANT CHECK»(/acura/rdx/i-2006-2009/remont/cooling-system-mechanical/#cooling-system) ).
  2. Remove the condenser fan shroud (see «FAN, FAN MOTOR, AND SHROUD REMOVAL AND INSTALLATION»(/acura/rdx/i-2006-2009/remont/cooling-system-mechanical/#cooling-system) ).
  3. Remove the lower hose, then remove the thermostat.
  4. Install the thermostat with a new O-ring, then install the lower hose.
  5. Install the condenser fan shroud (see «FAN, FAN MOTOR, AND SHROUD REMOVAL AND INSTALLATION»(/acura/rdx/i-2006-2009/remont/cooling-system-mechanical/#cooling-system) ).
  6. Refill the radiator with engine coolant, and bleed the air from the cooling system with the heater valve open (see step 6 ).

Scheme 15

Scheme 15: Water Passage Replacement
Scheme 15: Water Passage Replacement

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Scheme 21
Scheme 21
  1. Drain the engine coolant (see «COOLANT CHECK»(/acura/rdx/i-2006-2009/remont/cooling-system-mechanical/#cooling-system) ).
  2. Remove the intake manifold (see «REMOVAL»(/acura/rdx/i-2006-2009/remont/exhaust/#intake-manifold-and-exhaust-system) ).
  3. Remove the drive belt auto-tensioner (see «DRIVE BELT AUTO-TENSIONER REMOVAL/INSTALLATION»(/acura/rdx/i-2006-2009/remont/charging-system/#charging-system) ).
  4. Remove the alternator (see «ALTERNATOR REMOVAL AND INSTALLATION»(/acura/rdx/i-2006-2009/remont/charging-system/#charging-system) ).
  5. Remove the condenser fan shroud assembly.
  6. Remove the A/C compressor without disconnecting the A/C hoses (see step 38 under «ENGINE REMOVAL»(/acura/rdx/i-2006-2009/remont/mechanical/#engine-removal-and-installation) )..
  7. Remove the bolt (A) securing the connecting pipe.
  8. Remove the lower radiator hose (B), connecting pipe (C), water bypass hose (D), and harness clamp (E).
  9. Remove the water passage.
  10. Remove the thermostat housing.
  11. Remove the water pump (see «WATER PUMP REPLACEMENT»(/acura/rdx/i-2006-2009/remont/cooling-system-mechanical/#cooling-system__water-pump-replacement) ).
  12. Install the water pump (see «WATER PUMP REPLACEMENT»(/acura/rdx/i-2006-2009/remont/cooling-system-mechanical/#cooling-system__water-pump-replacement) ).
  13. Install the thermostat housing (A) with a new O-ring (B).
  14. Clean and dry the water passage mating surfaces.
  15. Apply liquid gasket, P/N 08717-0004, 08718-0001, 08718-0003, or 08718-0009, evenly to the engine block mating surface of the water passage. Install the component within 5 minutes of applying the liquid gasket. NOTE: If you apply liquid gasket P/N 08718-0012, the component must be installed within 4 minutes. If too much time has passed after applying the liquid gasket, remove the old liquid gasket and residue, then reapply new liquid gasket.
  16. Install the water passage (A) with a new O-ring (B). NOTE: Wait at least 30 minutes to allow liquid gasket to cure before filling the engine with oil. Do not run the engine for at least 3 hours after installing the water passage.
  17. Install the connecting pipe (A) with a new O-ring (B), then tighten the bolt (C).
  18. Install the lower radiator hose (D), water bypass hose (E), and harness clamp (F).
  19. Tighten the bolt (G) securing the connecting pipe.
  20. Install the A/C compressor (see step 30 under «ENGINE INSTALLATION»(/acura/rdx/i-2006-2009/remont/mechanical/#engine-removal-and-installation__engine-installation) ).
  21. Install the condenser fan shroud assembly.
  22. Install the alternator (see «INSTALLATION»(/acura/rdx/i-2006-2009/remont/charging-system/#charging-system) ).
  23. Install the drive belt auto-tensioner (see «DRIVE BELT AUTO-TENSIONER REMOVAL/INSTALLATION»(/acura/rdx/i-2006-2009/remont/charging-system/#charging-system) ).
  24. Install the intake manifold (see «INSTALLATION»(/acura/rdx/i-2006-2009/remont/exhaust/#intake-manifold-and-exhaust-system) ).
  25. Refill the radiator with engine coolant, and bleed the air from the cooling system with the heater valve open (see step 6 ).

Scheme 22

Scheme 22: Removal
Scheme 22: Removal

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Scheme 26
  1. Drain the engine coolant (see «COOLANT CHECK»(/acura/rdx/i-2006-2009/remont/cooling-system-mechanical/#cooling-system) ).
  2. Remove the air cleaner housing (see «AIR CLEANER REMOVAL/INSTALLATION»(/acura/rdx/i-2006-2009/remont/mechanical/#intake-air-system) ).
  3. Remove the charge air cooler (see «REMOVAL»(/acura/rdx/i-2006-2009/remont/exhaust/#intake-manifold-and-exhaust-system) )
  4. Remove the air bypass outlet pipe (A).
  5. Remove the ignition coil cover (A) and fuel feed pipe mounting bolt (B).
  6. Remove the engine wire harness connectors and wire harness clamps from the cylinder head. Camshaft position (CMP) sensor A (Intake) connector Camshaft position (CMP) sensor B (Exhaust) connector EVAP canister purge valve connector
  7. Remove the harness holder from the bracket.
  8. Remove the EVAP canister purge valve mounting bracket from the cylinder head.
  9. Remove the harness holder bracket (A), upper radiator hose (B), and water bypass hose (C), then remove the upper water outlet (D).
  10. Remove the heater hose (A) and water bypass hoses (B), then remove the lower water outlet (C).

Scheme 27

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Scheme 28

Scheme 28: Installation
Scheme 28: Installation

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Scheme 33
Scheme 33
  1. Install the lower water outlet (A) with a new O-ring (B), then install the water bypass hoses (C) and heater hose (D).
  2. Install the upper water outlet (A) with a new O-ring (B), then install the upper radiator hose (C), water bypass hose (D), and harness holder bracket (E).
  3. Install the EVAP canister purge valve mounting bracket.
  4. Install the harness holder.
  5. Install the engine wire harness connectors and wire harness clamps to the cylinder head. Camshaft position (CMP) sensor A (Intake) connector Camshaft position (CMP) sensor B (Exhaust) connector EVAP canister purge valve connector
  6. Install the ignition coil cover (A) and fuel feed pipe mounting bolt (B).
  7. Install the air bypass outlet pipe.
  8. Install the charge air cooler (see «INSTALLATION»(/acura/rdx/i-2006-2009/remont/exhaust/#intake-manifold-and-exhaust-system) ).
  9. Install the air cleaner housing (see «AIR CLEANER REMOVAL/INSTALLATION»(/acura/rdx/i-2006-2009/remont/mechanical/#intake-air-system) ).
  10. Refill the radiator with engine coolant, and bleed the air from the cooling system with the heater valve open (see step 6 ).

Scheme 34

Scheme 34: Removal
Scheme 34: Removal

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Scheme 37
  1. Remove the splash shield (see step 25 under «ENGINE REMOVAL»(/acura/rdx/i-2006-2009/remont/mechanical/#engine-removal-and-installation) ).
  2. Disconnect the fan motor connectors (A), and remove the harness clamps (B).
  3. Remove the clip (A), then remove the coolant reservoir (B) from the holder.
  4. Remove the clips (A), then remove the support rod clamp bracket (B).
  5. Remove the condenser fan shroud assembly (A), then remove the radiator fan shroud assembly (B) from the condenser fan shroud side.
  6. Disassemble the fan shrouds.

Scheme 38

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Scheme 39

Scheme 39: Installation
Scheme 39: Installation

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Scheme 43
  1. Assemble the fan shrouds.
  2. Install the radiator fan shroud assembly (A), then install the condenser fan shroud assembly (B).
  3. Install the support rod clamp bracket (A), then install the clips (B).
  4. Install the coolant reservoir.
  5. Connect the fan motor connectors (A), and install the harness clamps (B).
  6. Install the splash shield (see step 30 under «ENGINE INSTALLATION»(/acura/rdx/i-2006-2009/remont/mechanical/#engine-removal-and-installation__engine-installation) ).

Scheme 44

Scheme 44: Radiator Replacement
Scheme 44: Radiator Replacement

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Scheme 49
Scheme 49
  1. Drain the engine coolant (see «COOLANT CHECK»(/acura/rdx/i-2006-2009/remont/cooling-system-mechanical/#cooling-system) ).
  2. Remove the condenser fan shroud assembly and radiator fan shroud assembly (see «FAN, FAN MOTOR, AND SHROUD REMOVAL AND INSTALLATION»(/acura/rdx/i-2006-2009/remont/cooling-system-mechanical/#cooling-system) ).
  3. Remove the upper radiator hose (A).
  4. Clean any dirt off the quick connector (B), radiator, and lower radiator hose.
  5. Pull out the lock (C) by hand, then wiggle the quick connector loose, and remove it from the radiator. Do not use any tools to remove the quick connector.
  6. Remove the automatic transmission fluid (ATF) cooler hoses (D), then plug the hose and the line.
  7. Disconnect the engine coolant temperature (ECT) sensor 2 connector (E).
  8. Remove the intake air duct cover (A) and the four clips (B), then remove the upper radiator brackets (C).
  9. Pull up the radiator, then remove the radiator cap (A), ECT sensor 2 (B), and drain plug (C).
  10. Reassemble the radiator with new O-rings (D).
  11. Install the radiator. Make sure the lower cushions (E) are set securely.
  12. Install the upper radiator brackets (A), then install the intake air duct cover (B) and the four clips (C).
  13. Check the quick connector (A) and set ring (B) for cracks or damage. If the connector and/or set ring are cracked or damaged, replace the connector.
  14. Make sure the set ring is in place inside the quick connector. If the set ring is displaced or not properly seated in the connector, replace the quick connector.
  15. Replace the O-ring (C) in the quick connector.
  16. Check the lock (D). If the lock is damaged or deformed, replace it. When installing the new lock to the connector, slide it straight down along the groove.
  17. Install a new lower radiator hose on the quick connector, and install the clamp.
  18. Clean the connecting surface of the radiator (E), then apply clean engine coolant around the connecting surface.
  19. Push down the lock (A), then push the quick connector (B) onto the radiator until you hear it click.
  20. Install the upper radiator hose (C).
  21. Install the ATF cooler hoses (D), and connect the ECT sensor 2 connector (E).
  22. Install the condenser fan shroud assembly and radiator fan shroud assembly (see «FAN, FAN MOTOR, AND SHROUD REMOVAL AND INSTALLATION»(/acura/rdx/i-2006-2009/remont/cooling-system-mechanical/#cooling-system) ).
  23. Refill the radiator with engine coolant, and bleed the air from the cooling system with the heater valve open (see step 6 ).