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Makes 🢒 GMC_Truck 🢒 2001 🢒 GMC C Sierra - 2WD 🢒 Engine 🢒 Engine Cooling 🢒 Water Pump Replacement

Water Pump Replacement 4.3 L Engine

Tools Required

J 41240 Fan Clutch Remover and Installer

Removal Procedure

    Object Number: 360851 Size: SH
  1. Separate the MAF/IAT sensor assembly and the air inlet tube by loosening the hose clamp.
  2. Disconnect the PCV hose from the air cleaner outlet duct.

    3. Object Number: 489179 Size: SH
  3. Remove the air inlet tube and resonator retaining wing nut.

    4. Object Number: 489176 Size: SH
  4. Remove the air inlet tube and resonator from the throttle body by pivoting the air inlet tube and resonator upward until the hinge clip releases from the lip on the throttle body.
  5. Drain the cooling system. Refer to Cooling System Draining and Filling .
  6. Remove the upper fan shroud. Refer to Engine Coolant Fan Upper Shroud Replacement .
  7. Remove the cooling fan and clutch assembly. Refer to Fan Clutch Replacement .
  8. Remove the drive belt. Refer to Drive Belt Replacement in Engine Mechanical-4.3L.
  9. Remove the radiator outlet hose from the water pump. Refer to Radiator Outlet Hose Replacement .

    10. Object Number: 182853 Size: SH
  10. Remove the by-pass hose.

    11. Object Number: 317191 Size: SH
  11. Remove the bolts and the fan and water pump pulley using the J 41240 .

    12. Object Number: 188054 Size: SH
  12. Remove the water pump bolts.
  13. Remove the water pump.
  14. Remove the water pump gaskets.
  15. Discard the water pump gaskets.

    16. Object Number: 480571 Size: SH
  16. Remove the old gasket material from the water pump sealing surfaces.
  17. Clean all the dirt and any debris from the water pump.
  18. Inspect the water pump for the following:
    19. • Leakage or damage to the housing cover or gasket (1)
    • Excessive scratches or gouging to the gasket sealing surfaces (2)
    • Leakage from the water pump vent hole (3)
    • A stain around the vent hole is acceptable. If leakage occurred (dripping) with the engine operating and the cooling system pressurized, then replace the water pump.
    • Damaged bolt hole threads (4)
    • Excessive side-to-side movement of the water pump shaft (5)
    • Leakage around the water inlet pipe (6)
    • Leakage around the heater hose pipe (7)
    • Restrictions within the internal coolant passages

Installation Procedure

    Object Number: 188054 Size: SH
  1. If reusing the fasteners, apply sealant GM P/N 12346004 or equivalent to the threads of the water pump bolts.
  2. Install the water pump and the NEW water pump gaskets.

    3. Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  3. Install the water pump bolts.

    4. Tighten
    Tighten the water pump bolts to 45 N·m (33 lb ft).


    Object Number: 317191 Size: SH
  4. Install the fan and water pump pulley and bolts using the J 41240 .

    5. Tighten
    Tighten the fan and water pump pulley bolts to 25 N·m (18 lb ft).


    Object Number: 182853 Size: SH

    Important: After final assembly, the by-pass hose clamp tangs (water pump end) must point forward and the upper tang should be level with the outside diameter of the by-pass hose.

  5. Install the by-pass hose.
  6. Connect the radiator outlet hose to the water pump. Refer to Radiator Outlet Hose Replacement .
  7. Install the drive belt. Refer to Drive Belt Replacement in Engine Mechanical -4.3 L.
  8. Install the cooling fan and clutch assembly. Refer to Fan Clutch Replacement .
  9. Install the upper fan shroud. Refer to Engine Coolant Fan Upper Shroud Replacement .

    10. Object Number: 489176 Size: SH
  10. Align the hinge clip with the lip on the throttle body.

    11. Install the air inlet tube and resonator to the throttle body by pivoting the air inlet tube and resonator downward until the mounting stud is through the hole in the air inlet tube.


    Object Number: 489179 Size: SH
  11. Install the resonator retaining wing nut.

    12. Tighten
    Tighten the resonator wing nut to 3 N·m (27 lb in).

  12. Connect the PCV hose to the air cleaner outlet duct.

    13. Object Number: 373468 Size: SH
  13. Connect the MAF/IAT sensor assembly harness connector.
  14. Fill the cooling system. Refer to Cooling System Draining and Filling .
  15. Inspect the cooling system for leaks.

Water Pump Replacement 4.8L, 5.3L, and 6.0L Engines

Removal Procedure

    Object Number: 307286 Size: SH
  1. Drain the cooling system. Refer to Cooling System Draining and Filling .
  2. Loosen the air cleaner outlet duct clamps at the following locations:
    3. • Throttle body
    • Mass airflow/intake air temperature (MAF/IAT) sensor
  3. Remove the radiator inlet hose clip from the outlet duct.
  4. Remove the air cleaner outlet duct.

    5. Object Number: 659465 Size: SH
  5. If necessary, remove the engine sight shield. Refer to Upper Intake Manifold Sight Shield Replacement in Engine Mechanical - 4.8L, 5.3L, and 6.0L.
  6. Remove the radiator vent inlet hose from the radiator hose clips.

    7. Object Number: 659418 Size: SH
  7. Reposition the inlet hose clamp at the water pump.
  8. Remove the inlet hose from the water pump.
  9. Remove the fan blade. Refer to Fan Replacement .
  10. Remove the accessory drive belt. Refer to Drive Belt Replacement - Accessory in Engine Mechanical - 4.8L, 5.3L, and 6.0L.

    11. Object Number: 659509 Size: SH
  11. Reposition the outlet hose clamp at the water pump.
  12. Remove the outlet hose from the water pump.

    13. Object Number: 659180 Size: SH
  13. Reposition the surge tank outlet hose clamp at the water pump.
  14. Remove the surge tank outlet hose from the water pump.

    15. Object Number: 660665 Size: SH
  15. Reposition the heater inlet hose clamp at the water pump.
  16. Remove the heater inlet hose from the water pump.

    17. Object Number: 260121 Size: SH
  17. Remove the water pump bolts.
  18. Remove the water pump and gaskets.
  19. Discard the water pump gaskets.

Installation Procedure

Important: All gaskets surfaces are to be free of oil or other foreign material during assembly.


    Object Number: 260121 Size: SH
  1. Install the water pump and NEW gaskets.

    2. Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  2. Install the water pump bolts.

    3. Tighten

    1. Tighten the water pump bolts a first pass to 15 N·m (11 lb ft).
    2. Tighten the water pump bolts a final pass to 30 N·m (22 lb ft).

    Object Number: 660665 Size: SH
  3. Install the heater inlet hose to the water pump.
  4. Position the heater inlet hose clamp at the water pump.

    5. Object Number: 659180 Size: SH
  5. Install the surge tank outlet hose to the water pump.
  6. Position the surge tank outlet hose clamp at the water pump.

    7. Object Number: 659509 Size: SH
  7. Install the outlet hose to the water pump.
  8. Position the outlet hose clamp at the water pump.
  9. Install the accessory drive belt. Refer to Drive Belt Replacement - Accessory in Engine Mechanical - 4.8L, 5.3L, and 6.0L.
  10. Install the fan blade. Refer to Fan Replacement .

    11. Object Number: 659418 Size: SH
  11. Install the inlet hose to the water pump.
  12. Position the inlet hose clamp at the water pump.

    13. Object Number: 659465 Size: SH
  13. Install the engine vent inlet hose to the radiator hose clips.
  14. If necessary, install the engine sight shield. Refer to Upper Intake Manifold Sight Shield Replacement in Engine Mechanical - 4.8L, 5.3L, and 6.0 L.

    15. Object Number: 307286 Size: SH

    Important: Align the arrow at the throttle body end of the duct with the throttle body attaching stud.

  15. Install the air cleaner outlet duct.
  16. Install the radiator inlet hose clip to the outlet duct.
  17. Tighten the air cleaner outlet duct clamps at the following locations:
    18. • Throttle body
    • MAF/IAT sensor

    Tighten
    Tighten the air cleaner outlet duct clamp screws to 7 N·m (62 lb in).

  18. Fill the cooling system. Refer to Cooling System Draining and Filling .

Water Pump Replacement 8.1L Engine

Removal Procedure

    Object Number: 751427 Size: SH
  1. Drain the cooling system. Refer to Cooling System Draining and Filling .
  2. Remove the drive belt. Refer to Drive Belt Replacement - Accessory in Engine Mechanical - 8.1 L.
  3. Remove the fan clutch. Refer to Fan Clutch Replacement .
  4. Reposition the outlet hose clamp at the water pump.
  5. Remove the outlet hose from the water pump.

    6. Object Number: 470692 Size: SH
  6. Reposition the bypass hose clamps at the water pump and water crossover.
  7. Remove the bypass hose.

    8. Object Number: 470790 Size: SH
  8. Remove the water pump bolts.
  9. Remove the water pump.
  10. Remove and discard the water pump gaskets.

Installation Procedure

    Object Number: 470790 Size: SH
  1. Place NEW water pump gaskets into place.
  2. Install the water pump.

    3. Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  3. Install the water pump bolts.

    4. Tighten
    Tighten the water pump bolts to 50 N·m (37 lb ft).


    Object Number: 470692 Size: SH
  4. Install the bypass hose.
  5. Position the bypass hose clamps at the water pump and water crossover.

    6. Object Number: 751427 Size: SH
  6. Install the outlet hose to the water pump.
  7. Position the outlet hose clamp at the water pump.
  8. Install the fan clutch. Refer to Fan Clutch Replacement .
  9. Install the drive belt. Refer to Drive Belt Replacement - Accessory in Engine Mechanical - 8.1 L.
  10. Fill the cooling system. Refer to Cooling System Draining and Filling .

Water Pump Replacement 6.6 L Engine

Removal Procedure


    Object Number: 401885 Size: SH
  1. Remove the left front fender wheelhouse inner panel (1).
  2. Drain the engine coolant and the engine block. Refer to Cooling System Draining and Filling .
  3. Remove the thermostat housing crossover. Refer to Thermostat Housing Crossover Replacement .
  4. Remove the fan clutch. Refer to Fan Clutch Replacement .
  5. Remove the crankshaft balancer. Refer to Crankshaft Balancer Replacement in Engine Mechanical - 6.6L.

    6. Object Number: 660519 Size: SH
  6. Remove the water pump outlet pipe to water pump nuts.
  7. Remove the engine wiring harness retainer from the inner stud.

    8. Object Number: 660521 Size: SH
  8. Remove the water pump bolts. Note the location of the bolts. The bolts are three different lengths.
  9. Remove the water pump assembly.
  10. Remove the water pump outlet pipe gasket.

Inspection and Repair Procedure

    Object Number: 663772 Size: SH
  1. Remove the O-ring from the water pump.
  2. Remove the water pump to water pump housing bolts.
  3. Remove the water pump from the water pump housing.
  4. Remove the O-ring from the water pump housing.

    5. Object Number: 663773 Size: SH
  5. Clean the water pump assembly.
  6. Clean the water pump mating surfaces.
  7. Inspect the water pump gear for damage.
  8. Inspect the water pump mating surfaces for damage.
  9. Inspect the water pump shaft for looseness.
  10. Inspect the water pump assembly for damage.
  11. Replace the water pump if any damage is found.

    12. Object Number: 663772 Size: SH
  12. Install a new O-ring to the water pump housing.
  13. Lubricate the O-ring with engine coolant.
  14. Install the water pump to the water pump housing.

    15. Notice: Refer to Fastener Notice in the Preface section.

  15. Install the water pump to water pump housing bolts.

    16. Tighten
    Tighten the water pump to water pump housing bolts to 21 N·m (15 lb ft).

  16. Install a new O-ring to the water pump.

Installation Procedure

    Object Number: 660521 Size: SH
  1. Lubricate the water pump O-ring with engine oil.
  2. Install the water pump.
  3. Install the water pump bolts. Ensure the correct length bolt is used in the proper location.

    4. Tighten
    Tighten the water pump bolts to 21 N·m (15 lb ft).


    Object Number: 660519 Size: SH
  4. Install the water pump to water pump outlet pipe gasket.
  5. Install the engine wiring harness retainer on the water pump outlet pipe inner stud.
  6. Install the water pump to water pump outlet pipe nuts.

    7. Tighten
    Tighten the water pump to water pump outlet pipe nuts to 21 N·m (15 lb ft).


    Object Number: 401885 Size: SH
  7. Install the thermostat housing crossover. Refer to Thermostat Housing Crossover Replacement .
  8. Install the crankshaft balancer. Refer to Crankshaft Balancer Replacement in Engine Mechanical - 6.6L.
  9. Install the fan clutch. Refer to Fan Clutch Replacement .
  10. Fill the engine with coolant. Refer to Cooling System Draining and Filling .
  11. Install the left front fender wheelhouse inner panel (1).