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Water Pump Replacement (4.3L Engine) Chevrolet Silverado 2500

Engine Cooling System: Removal & Installation 35 illustrations ~3099 words

Water Pump Replacement (4.3L Engine)

Tools Required

J 41240 Fan Clutch Remover and Installer

Scheme 125

Scheme 125: Removal Procedure
Scheme 125: Removal Procedure

Scheme 126

Scheme 126
Scheme 126

Scheme 127

Scheme 127
Scheme 127

Scheme 128

Scheme 128
Scheme 128

Scheme 129

Scheme 129
Scheme 129

Scheme 130

Scheme 130
Scheme 130

Scheme 131

Scheme 131
Scheme 131
  1. Loosen the air cleaner outlet duct clamp at the mass airflow/intake air temperature sensor.
  2. Remove the positive crankcase ventilation (PCV) hose.
  3. Remove the air cleaner adapter nut.
  4. In order to remove the air cleaner outlet duct, pivot the duct upward until the hinge clip release from the lip on the throttle body.
  5. Drain the cooling system. Refer to «Draining & Filling Cooling System»(ref-176275-S33324703732005050500000) .
  6. Remove the cooling fan. Refer to «Fan Replacement»(ref-176275-S09518946662005050500000) .
  7. Remove the drive belt.
  8. Reposition the radiator outlet hose clamps at the surge tank and water pump.
  9. Remove the radiator outlet hose from the surge tank.
  10. Remove the radiator outlet hose from the water pump.
  11. Reposition the water pump inlet hose clamps.
  12. Remove the water pump inlet hose.
  13. Using J 41240 to hold the water pump pulley, remove the water pump pulley bolts.
  14. Remove the water pump bolts.
  15. Remove the water pump.
  16. Remove and discard the water pump gaskets.
  17. Clean and inspect the water pump, if necessary.
  1. If reusing the fasteners, apply sealant GM P/N United States 12346004, GM P/N Canada 10953480, or equivalent to the threads of the water pump bolts.
  2. Install NEW water pump gaskets and the water pump.
  3. Install the water pump bolts. Tighten the water pump bolts to 45 N.m (33 lb ft).
  4. Using J 41240 to hold the water pump pulley, install the water pump pulley bolts. Tighten the water pump pulley bolts to 25 N.m (18 lb ft). Important: After assembly, the hose clamp tangs (water pump end) must point forward and the upper tang should be level with the outside diameter of the water pump inlet hose.
  5. Install the water pump inlet hose.
  6. Position the water pump inlet hose clamps.
  7. Install the radiator outlet hose to the water pump.
  8. Install the radiator outlet hose to the surge tank.
  9. Position the radiator outlet hose clamps at the surge tank and water pump.
  10. Install the drive belt.
  11. Install the cooling fan. Refer to «Fan Replacement»(ref-176275-S09518946662005050500000) .
  12. Align the hinge clip with the lip on the throttle body. In order to install the air cleaner outlet duct, pivot the air cleaner outlet duct downward until the mounting stud is through the hole.
  13. Install the air cleaner adapter nut.
  14. Install the PCV hose.
  15. Tighten the air cleaner outlet duct clamp at the MAF/IAT sensor.
  16. Fill the cooling system. Refer to «Draining & Filling Cooling System»(ref-176275-S33324703732005050500000) .
  17. Inspect the cooling system for leaks.

Scheme 132

Scheme 132: Removal Procedure
Scheme 132: Removal Procedure

Scheme 133

Scheme 133
Scheme 133

Scheme 134

Scheme 134
Scheme 134

Scheme 135

Scheme 135
Scheme 135

Scheme 136

Scheme 136
Scheme 136

Scheme 137

Scheme 137
Scheme 137
  1. Drain the cooling system. Refer to «Draining & Filling Cooling System»(ref-176275-S33324703732005050500000) .
  2. Loosen the air cleaner outlet duct clamps at the following locations: 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. If necessary, remove the engine sight shield.
  6. Remove the radiator vent inlet hose from the radiator hose clips.
  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»(ref-176275-S09518946662005050500000) .
  10. Remove the accessory drive belt.
  11. Reposition the outlet hose clamp at the water pump.
  12. Remove the outlet hose from the water pump.
  13. Reposition the surge tank outlet hose clamp at the water pump.
  14. Remove the surge tank outlet hose from the water pump.
  15. Reposition the heater inlet hose clamp at the water pump.
  16. Remove the heater inlet hose from the water pump.
  17. Remove the water pump bolts.
  18. Remove the water pump and gaskets.
  19. Discard the water pump gaskets.

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

  1. Install the water pump and NEW gaskets.
  2. Install the water pump bolts. 2.1. Tighten the water pump bolts a first pass to 15 N.m (11 lb ft). 2.2. Tighten the water pump bolts a final pass to 30 N.m (22 lb ft).
  3. Install the heater inlet hose to the water pump.
  4. Position the heater inlet hose clamp at the water pump.
  5. Install the surge tank outlet hose to the water pump.
  6. Position the surge tank outlet hose clamp at the water pump.
  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.
  10. Install the fan blade. Refer to «Fan Replacement»(ref-176275-S09518946662005050500000) .
  11. Install the inlet hose to the water pump.
  12. Position the inlet hose clamp at the water pump.
  13. Install the engine vent inlet hose to the radiator hose clips.
  14. If necessary, install the engine sight shield. 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: Throttle body MAF/IAT sensor Tighten the air cleaner outlet duct clamp screws to 7 N.m (62 lb in).
  18. Fill the cooling system. Refer to «Draining & Filling Cooling System»(ref-176275-S33324703732005050500000) .

Scheme 138

Scheme 138: Removal Procedure
Scheme 138: Removal Procedure
  1. Remove the left front fender wheelhouse inner panel (1).
  2. Drain the engine coolant and the engine block. Refer to «Draining & Filling Cooling System»(ref-176275-S33324703732005050500000) .
  3. Remove the thermostat housing crossover. Refer to «Thermostat Housing Crossover Replacement (6.6L Engine)»(ref-176275-S23281057122005050500000) .
  4. Remove the fan clutch. Refer to «Fan Replacement»(ref-176275-S09518946662005050500000) .
  5. Remove the crankshaft balancer.
  6. Remove the water pump outlet pipe to water pump nuts.
  7. Remove the engine wiring harness retainer from the inner stud.
  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.
  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. Tighten the water pump bolts to 21 N.m (15 lb ft).
  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. Tighten the water pump to water pump outlet pipe nuts to 21 N.m (1 lb ft).
  7. Install the thermostat housing crossover. Refer to «Thermostat Housing Crossover Replacement (6.6L Engine)»(ref-176275-S23281057122005050500000) .
  8. Install the crankshaft balancer.
  9. Install the fan clutch. Refer to «Fan Replacement»(ref-176275-S09518946662005050500000) .
  10. Fill the engine with coolant. Refer to «Draining & Filling Cooling System»(ref-176275-S33324703732005050500000) .
  11. Install the left front fender wheelhouse inner panel (1).

Scheme 139

Scheme 139: Removal Procedure
Scheme 139: Removal Procedure

Scheme 140

Scheme 140
Scheme 140

Scheme 141

Scheme 141
Scheme 141
  1. Drain the cooling system. Refer to «Draining & Filling Cooling System»(ref-176275-S33324703732005050500000) .
  2. Remove the drive belt.
  3. Remove the fan clutch. Refer to «Fan Replacement»(ref-176275-S09518946662005050500000) .
  4. Reposition the outlet hose clamp at the water pump.
  5. Remove the outlet hose from the water pump.
  6. Reposition the bypass hose clamps at the water pump and water crossover.
  7. Remove the bypass hose.
  8. Remove the water pump bolts.
  9. Remove the water pump.
  10. Remove and discard the water pump gaskets.
  1. Place NEW water pump gaskets into place.
  2. Install the water pump.
  3. Install the water pump bolts. Tighten the water pump bolts to 50 N.m (37 lb ft).
  4. Install the bypass hose.
  5. Position the bypass hose clamps at the water pump and water crossover.
  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 Replacement»(ref-176275-S09518946662005050500000) .
  9. Install the drive belt.
  10. Fill the cooling system. Refer to «Draining & Filling Cooling System»(ref-176275-S33324703732005050500000) .
  1. Remove the left front fender wheelhouse inner panel (1).
  2. Remove the water pump. Refer to «Water Pump Replacement (6.6L Engine)»(ref-176275-S37414164702005050500000) .
  3. Remove the water pump outlet pipe from the engine oil cooler assembly.
  4. Remove and discard the O-ring seal.
  5. Remove the gasket and clean the sealing surface.
  1. Install a new O-ring seal on the water pump outlet pipe.
  2. Lightly lubricate the O-ring seal with engine oil.
  3. Install the water pump outlet pipe in the engine oil cooler assembly.
  4. Install a new water pump outlet pipe to water pump gasket.
  5. Install the water pump.
  6. Install the left front fender wheelhouse inner panel (1).

Scheme 142

Scheme 142: Removal Procedure
Scheme 142: Removal Procedure
  1. Drain the cooling system. Refer to «Draining & Filling Cooling System»(ref-176275-S33324703732005050500000) .
  2. Remove the radiator drain cock.
  1. Install the radiator drain cock.
  2. Fill the cooling system. Refer to «Draining & Filling Cooling System»(ref-176275-S33324703732005050500000) .

Scheme 143

Scheme 143: Removal Procedure
Scheme 143: Removal Procedure

Scheme 144

Scheme 144
Scheme 144

Scheme 145

Scheme 145
Scheme 145
  1. Loosen the air cleaner outlet duct clamps from the throttle body.
  2. Loosen the air cleaner outlet duct clamps from the mass airflow sensor.
  3. Remove the air cleaner outlet duct.
  4. Remove the throttle body heater hose retainer from the fan shroud.
  5. Remove the inlet radiator hose retainer from the fan shroud.
  6. Remove the fan shroud retainers.
  7. Remove the fan shroud bolts
  8. Remove the upper fan shroud.
  1. Install the upper fan shroud.
  2. Install the fan shroud bolts. Tighten the bolts to 9 N.m (80 lb in).
  3. Install the fan shroud retainers.
  4. Install the inlet radiator hose retainer to the fan shroud
  5. Install the throttle body heater hose retainer to the fan shroud.
  6. Install the air cleaner outlet duct.
  7. Tighten the air cleaner outlet duct clamp at the throttle body. Tighten the clamp screw to 7 N.m (62 lb in).
  8. Tighten the air cleaner outlet duct clamp at the mass airflow sensor. Tighten the clamp screw to 7 N.m (62 lb in).

Scheme 146

Scheme 146: Removal Procedure
Scheme 146: Removal Procedure

Scheme 147

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Scheme 147

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Scheme 148

Scheme 149

Scheme 149
Scheme 149
  1. Loosen the air cleaner outlet duct clamps from the throttle body.
  2. Loosen the air cleaner outlet duct clamps from the mass airflow sensor.
  3. Remove the air cleaner outlet duct.
  4. Remove the A/C line retainer from the fan shroud.
  5. Remove the engine harness clip from the PCM cover.
  6. Remove the TCM cover bolts.
  7. Remove TCM cover from the fan shroud.
  8. Loosen the TCM electrical connector bolts.
  9. Disconnect the TCM electrical connectors (1).
  10. Remove the TCM and cover.
  11. Remove the fan shroud retainers.
  12. Remove the fan shroud bolts
  13. Remove the upper fan shroud.
  1. Install the upper fan shroud.
  2. Install the fan shroud bolts. Tighten the bolts to 9 N.m (80 lb in).
  3. Install the fan shroud retainers.
  4. Connect the TCM electrical connectors (1).
  5. Install the TCM and cover.
  6. Tighten the TCM electrical connector bolts. Tighten the bolts to 8 N.m (71 lb in).
  7. Install the TCM cover to the fan shroud.
  8. Install the TCM cover bolts. Tighten the to 9 N.m (80 lb in).
  9. Install the engine harness clip to the PCM cover.
  10. Install the A/C line retainer to the fan shroud.
  11. Install the air cleaner outlet duct.
  12. Tighten the air cleaner outlet duct clamp at the throttle body. Tighten the clamp screws to 7 N.m (62 lb in).
  13. Tighten the air cleaner outlet duct clamp at the mass airflow sensor. Tighten the clamp screws to 7 N.m (62 lb in).
  1. Remove the cooling fan. Refer to «Fan Replacement»(ref-176275-S09518946662005050500000) .
  2. If equipped with engine oil cooler, remove the oil cooler hose clip from the lower fan shroud.
  3. Lift the lower fan shroud up in order to disengage the fan shroud from the retaining clips on the radiator.
  1. Install the lower fan shroud to the retaining clips on the radiator and firmly push down.
  2. If equipped with the engine oil cooler, Install the oil cooler hose clip to the lower fan shroud.
  3. Install the cooling fan. Refer to «Fan Replacement»(ref-176275-S09518946662005050500000) .

Scheme 150

Scheme 150: Removal Procedure
Scheme 150: Removal Procedure

Scheme 151

Scheme 151
Scheme 151
  1. Drain the cooling system. Refer to «Draining & Filling Cooling System»(ref-176275-S33324703732005050500000)
  2. Reposition the inlet hose clamp from the radiator.
  3. Remove the inlet hose from the radiator.
  4. Reposition the outlet hose clamp from the radiator.
  5. Remove the radiator outlet hose from the radiator.
  6. Remove the lower fan shroud. Refer to «Fan Shroud Replacement - Lower»(ref-176275-S30244706742005050500000) .
  7. Reposition the radiator vent inlet hose clamp from the radiator.
  8. Remove the vent inlet hose from the radiator.
  9. Remove the engine oil cooler lines from the radiator.
  10. Remove the transmission oil cooler lines from the radiator.
  11. Remove the radiator bolts.
  12. Remove the radiator from the vehicle.
  1. Install the radiator to the vehicle.
  2. Install the radiator bolts. Tighten the bolts to 25 N.m (18 lb ft).
  3. Install the engine oil cooler lines to the radiator. Refer to «Engine Oil Cooler Hose/Pipe Replacement (6.0L & 8.1L Engines)»(ref-176275-S23676708492005050500000) .
  4. Install the transmission oil cooler lines to the radiator.
  5. Install the radiator vent inlet hose to the radiator.
  6. Reposition the radiator vent inlet hose clamp to the radiator.
  7. Install the lower fan shroud. Refer to «Fan Shroud Replacement - Lower»(ref-176275-S30244706742005050500000) .
  8. Install the outlet hose to the radiator.
  9. Reposition the outlet hose clamp to the radiator.
  10. Install the inlet hose to the radiator.
  11. Reposition the inlet hose clamp to the radiator.
  12. Fill the cooling system. Refer to «Draining & Filling Cooling System»(ref-176275-S33324703732005050500000)

Scheme 152

Scheme 152: Removal Procedure
Scheme 152: Removal Procedure
  1. Remove the radiator air upper baffle retainers.
  2. Remove the radiator air upper baffle.
  1. Install the radiator air upper baffle.
  2. Install the radiator air upper baffle retainers.

Scheme 153

Scheme 153: Removal Procedure
Scheme 153: Removal Procedure
  1. Remove the radiator. Refer to «Radiator Replacement»(ref-176275-S05176518402005050500000) .
  2. Remove the radiator air baffle retainers.
  3. Remove the radiator air baffles.
  1. Install the radiator air baffles.
  2. Install the radiator air baffle retainers.
  3. Install the radiator. Refer to «Radiator Replacement»(ref-176275-S05176518402005050500000) .
  1. Drain the cooling system. Refer to «Draining & Filling Cooling System»(ref-176275-S33324703732005050500000) .
  2. Disconnect the heater cord from the coolant heater (4).
  3. Loosen the bolt retaining the coolant heater to the block.
  4. Remove the coolant heater from the engine block.
  5. Do not score the machined surface of the hole.
  6. Grasp the plug with pliers.
  7. Pull the plug from the engine block.
  8. Clean the core plug hole in order to remove the following substances: Burrs Compound Paint Rough spots

Scheme 154

Scheme 154: Installation Procedure
Scheme 154: Installation Procedure
  1. Coat the O-ring seal and the cleaned surface of the plug opening with water resistant high-temperature grease GM P/N United States 1052196, GM P/N Canada 5264008, or the equivalent. Important: Avoid element contact with the inside walls of the engine block.
  2. Tightly push the coolant heater (1) into the engine block.
  3. Tighten the bolt on the engine coolant heater until both of the locking wings draw tightly against the inner wall of the engine block. Tighten the bolt in order to retain the engine coolant heater to the engine block to 2 N.m (18 lb in). NOTE: The heater cord must not touch the engine, hot pipes, manifold, or any moving parts. Route the cord to the left front of the engine compartment securing with tie straps as necessary to prevent damage.
  4. Connect the heater cord to the coolant heater (4).
  5. Fill the cooling system. Refer to «Draining & Filling Cooling System»(ref-176275-S33324703732005050500000) .
  6. Inspect the cooling system for leaks.

Scheme 155

Scheme 155: Removal Procedure
Scheme 155: Removal Procedure
  1. Drain the cooling system. Refer to «Draining & Filling Cooling System»(ref-176275-S33324703732005050500000) .
  2. Raise and suitably support the vehicle.
  3. Disconnect the coolant heater electrical connector (2). Important: Do not score the surface of the engine block hole when removing the coolant heater.
  4. Remove the coolant heater from the engine block.
  5. Remove any burrs, sealer, paint or other rough spots.
  1. If re-using the old coolant heater, apply thread sealant GM P/N United States 12346004, GM P/N Canada 10953480, or equivalent to the threads.
  2. Install the coolant heater to the engine block. Tighten the coolant heater to 50 N.m (37 lb ft). NOTE: The heater cord must not touch the engine, hot pipes, manifold, or any moving parts. Route the cord to the left front of the engine compartment securing with tie straps as necessary to prevent damage.
  3. Connect the coolant heater electrical connector (2).
  4. Lower the vehicle.
  5. Fill the cooling system. Refer to «Draining & Filling Cooling System»(ref-176275-S33324703732005050500000) .

Scheme 156

Scheme 156: Removal Procedure
Scheme 156: Removal Procedure
  1. Drain the cooling system and the engine block. Refer to «Draining & Filling Cooling System»(ref-176275-S33324703732005050500000) .
  2. Raise the vehicle.
  3. Remove the right front tire and wheel.
  4. Remove the right front fender wheelhouse inner fender (1).
  5. Remove the right engine mount.
  6. Disconnect the engine coolant heater cord.
  7. Loosen the bolt retaining the engine coolant heater to the block.
  8. Remove the engine coolant heater from the engine block.
  9. Do not score the machined surface of the hole.
  10. Grasp the plug with pliers.
  11. Pull the plug from the engine block.
  12. Clean the core plug hole in order to remove the following substances: Burrs Compound Paint Rough spots
  1. Coat the O-ring seal and the cleaned surface of the plug opening with water resistant high-temperature grease GM P/N United States 1052196, GM P/N Canada 5264008, or the equivalent. Important: Avoid element contact with the inside walls of the engine block.
  2. Align the coolant heater element to point towards the top of the engine.
  3. Tightly push the coolant heater into the engine block.
  4. Tighten the bolt on the engine coolant heater until both of the locking wings draw tightly against the inner wall of the engine block. Tighten the bolt in order to retain the engine coolant heater to the engine block to 2 N.m (18 lb in). NOTE: The heater cord must not touch the engine, hot pipes, manifold, or any moving parts. Route the cord to the left front of the engine compartment securing with tie straps as necessary to prevent damage.
  5. Connect the heater cord to the coolant heater.
  6. Install the right engine mount.
  7. Install the right front fender wheelhouse inner fender (1).
  8. Install the right front tire and wheel.
  9. Lower the vehicle.
  10. Fill the cooling system. Refer to «Draining & Filling Cooling System»(ref-176275-S33324703732005050500000) .
  11. Inspect for coolant leaks.

Scheme 157

Scheme 157: Removal Procedure
Scheme 157: Removal Procedure

Scheme 158

Scheme 158
Scheme 158
  1. Drain the cooling system. Refer to «Draining & Filling Cooling System»(ref-176275-S33324703732005050500000) .
  2. Disconnect the block heater cord from the block heater.
  3. Remove the engine block heater.
  1. Apply sealant GM P/N 12346004, Canadian P/N 10953480 or equivalent to the threads of the engine block heater.
  2. Install the engine block heater into the block. Tighten the engine block heater to 60 N.m (40 lb ft). NOTE: The heater cord must not touch the engine, hot pipes, manifold, or any moving parts. Route the cord to the left front of the engine compartment securing with tie straps as necessary to prevent damage.
  3. Connect the block heater cord to the block heater.
  4. Fill the cooling system. Refer to «Draining & Filling Cooling System»(ref-176275-S33324703732005050500000) .

Scheme 159

Scheme 159: Removal Procedure
Scheme 159: Removal Procedure
  1. Raise and suitably support the vehicle.
  2. Disconnect the coolant heater electrical connector (2).
  3. Remove the coolant heater cord retainer and bolts.
  4. Remove the coolant heater cord.

Note. The heater cord must not touch the engine, hot pipes, manifold, or any moving parts. Route the cord to the left front of the engine compartment securing with tie straps as necessary to prevent damage.

  1. Install the coolant heater cord.
  2. Install the coolant heater cord bolts and retainer. Tighten the coolant heater cord bolts to 8 N.m (71 lb in).
  3. Connect the coolant heater electrical connector (2).
  4. Lower the vehicle.