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    Avalanche, Sierra, Silverado, C&K Series, 1999-2005

    Injection Pump

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    All vehicles are equipped with an electronically controlled pump. The electronic pump is driven by gears and rotates at the same speed as the camshaft. An electronic stepper motor used to control injection timing and a fuel solenoid driver used to control the fuel injection solenoid on the electronic model.

    All vehicles are equipped with an electronically controlled pump. The electronic pump is driven by gears and rotates at the same speed as the camshaft. An electronic stepper motor used to control injection timing and a fuel solenoid driver used to control the fuel injection solenoid on the electronic model.

    All vehicles are equipped with an electronically controlled pump. The electronic pump is driven by gears and rotates at the same speed as the camshaft. An electronic stepper motor used to control injection timing and a fuel solenoid driver used to control the fuel injection solenoid on the electronic model.

    All vehicles are equipped with an electronically controlled pump. The electronic pump is driven by gears and rotates at the same speed as the camshaft. An electronic stepper motor used to control injection timing and a fuel solenoid driver used to control the fuel injection solenoid on the electronic model.

    Removal & Installation



    1. Before servicing the vehicle, refer to the Precautions section.
    2.  
    3. Relieve the fuel system pressure.
    4.  
    5. Remove or disconnect the following:
      NOTE
      Do not engage the starter in order to rotate the engine with the injection pump removed. The pump driven gear could jam in the front housing resulting in a sheared crankshaft or camshaft gear key and possible valvetrain damage.



      Negative battery cables
       
      Intake manifold
       
      Fuel injection and inlet lines
       
      Cables wires, and hoses at the injection pump
       
      Fuel return line at the top of the injection pump
       
      Fuel feed line at the injection pump, if necessary
       
      Oil filler tube grommet
       

    6.  
    7. Scribe or paint a matchmark on the front cover and the injection pump flange.
    8.  
    9. Rotate the crankshaft by hand and remove the injection pump driven gear bolts, accessing the bolts through the oil filler neck hole.
    10.  
    11. Remove the injection pump-to-front cover attaching nuts. Remove the pump. Be sure to cap all open lines and nozzles in order to prevent system contamination and damage.
    12.  

    To install:

    Click image to see an enlarged view

    Fig. Align the pin on the pump hub with the slot in the driven gear, NOT into the hole in the gear-diesel engines

    1. Align the locating pin on the pump hub with the slot in the injection pump driven gear (the SLOT not the hole in the gear) At the same time, align the timing marks.
    2.  
    3. Attach the injection pump to the front cover. Torque the nuts to 30 ft. lbs. (40 Nm) checking the timing marks before tightening.
    4.  
    5. Install or connect the following:

      Driven gear-to-injection pump bolts. Torque the bolts to 20 ft. lbs. (25 Nm).
       
      Grommet and oil fill tube
       
      Air conditioning bracket. If applicable
       
      Fuel feed line. Torque to 20 ft. lbs. (25 Nm).
       
      Fuel return line to the pump, if removed
       
      Cables, wires and hoses previously removed
       
      Injector lines
       
      Intake manifold
       
      Negative battery cables
       

    6.  
    7. Start the engine and check for leaks.
    8.  

    1. Drain the cooling system
    2.  
    3. Remove or disconnect the following:

      Negative battery cables
       
      Air intake duct. Cover the end to prevent dirt from entering
       
      Intake manifold cover
       
      Fuel fill cap in order to relieve the fuel pressure
       
      Fuel Injection Control Module (FICM) electrical connectors
       
      Fuel injection control module
       
      Upper fan shroud
       
      Fan blade assembly
       
      Drive belt
       
      Bolt holding the positive battery cable junction box and bracket and position aside
       
      A/C compressor and power steering pump and position aside with the lines attached
       
      Oil dipstick tube
       
      A/C and power steering pump bracket
       
      Drive belt tensioner and bolt.
       
      Alternator
       
      Thermostat housing bracket, wiring and fuel test port and 2 nuts
       
      Positive Crankcase Ventilation (PCV) catch tank from the PCV bracket and the bolt below holding the lower line, then position aside
       
      Alternator bracket
       
      Turbo cooling hose return line clamp and hose
       
      Upper radiator hose at the outlet pipe. Remove the bracket and support the bracket at the valve cover and swing out of the way
       
      Bolt holding the wiring support bracket at the thermostat housing
       

    4.  
    5. Move the main wiring harness by disconnecting the following:
      1. The fuel pressure regulator connector on the fuel injection pump
      2.  
      3. Fuel injection control module connectors
      4.  

    6.  
    7. Flip the wire harness and harness tray toward the back and position aside.
    8.  
    9. Remove or disconnect the following:
      NOTE
      Cap all open fuel connections to prevent contaminants from entering.


      NOTE
      When removing the pump, be careful not to damage any of the mating surfaces.



      Heater pipe bolt and temperature sensor wire from the thermostat housing
       
      Air intake pipe
       
      Water crossover assembly
       
      Hose from the turbo water feed line
       



      High pressure fuel lines and support pipe and hose at the fuel injection pump and junction block
       
      Fuel return hose from the fuel injection pump
       
      Y-junction banjo fitting from the junction block
       
      Bolts securing the fuel injection pump at the front cover and block
       



      Fuel injection pump from the block using 2 pry tools to work the pump from the block toward the rear of the engine, keeping the pump straight.

      Click image to see an enlarged view

      Fig. Diesel fuel injection pump-6.6L engines

       

    10.  
    11. Prepare the fuel pump as follows:
      1. Hold the fuel pump by the drive gear in a vise with copper jaw liners.
      2.  
      3. Loosen the gear nut until the nut is even with the end of the gear shaft.
      4.  
      5. Separate the pump and adapter by removing the 3 bolts and spacers.
      6.  
      7. Inspect the O-ring for damage on the pump adapter and replace if necessary. Lubricate the O-ring with clean engine oil.
      8.  
      9. Clean all mating surfaces.
      10.  
      11. Install the adapter on the pump
      12.  
      13. Using the bolts and spacers, reassemble the pump. Tighten the bolts to 15 ft. lbs. (20 Nm).
      14.  
      15. Install the gear and nut and tighten to 52 ft. lbs. (70 Nm).
      16.  

    12.  

    To install:

    1. Installation is the reverse of removal, noting the following tightening specifications:

      Fuel injection pump mounting bolts: 15 ft. lbs. (20 Nm)
       
      Y-junction banjo fitting: 11 ft. lbs. (15 Nm)
       
      High pressure fuel lines: 40 ft. lbs. (54 Nm)
       
      Heater pipe bracket and water crossover bolts: 15 ft. lbs. (20 Nm)
       
      Upper radiator hose mounting bolts: 89 inch lbs. (10 Nm)
       
      A/C and power steering pump bracket bolts: 34 ft. lbs. (46 Nm)
       

    2.  
    3. Refill the cooling system, then start the engine and check for leaks.
    4.  

    1. Drain the cooling system
    2.  
    3. Remove or disconnect the following:

      Negative battery cables
       
      Air intake duct. Cover the end to prevent dirt from entering
       
      Intake manifold cover
       
      Fuel fill cap in order to relieve the fuel pressure
       
      Fuel Injection Control Module (FICM) electrical connectors
       
      Fuel injection control module
       
      Upper fan shroud
       
      Fan blade assembly
       
      Drive belt
       
      Bolt holding the positive battery cable junction box and bracket and position aside
       
      A/C compressor and power steering pump and position aside with the lines attached
       
      Oil dipstick tube
       
      A/C and power steering pump bracket
       
      Drive belt tensioner and bolt.
       
      Alternator
       
      Thermostat housing bracket, wiring and fuel test port and 2 nuts
       
      Positive Crankcase Ventilation (PCV) catch tank from the PCV bracket and the bolt below holding the lower line, then position aside
       
      Alternator bracket
       
      Turbo cooling hose return line clamp and hose
       
      Upper radiator hose at the outlet pipe. Remove the bracket and support the bracket at the valve cover and swing out of the way
       
      Bolt holding the wiring support bracket at the thermostat housing
       

    4.  
    5. Move the main wiring harness by disconnecting the following:
      1. The fuel pressure regulator connector on the fuel injection pump
      2.  
      3. Fuel injection control module connectors
      4.  

    6.  
    7. Flip the wire harness and harness tray towards the back and position aside.
    8.  
    9. Remove or disconnect the following:
      NOTE
      Cap all open fuel connections to prevent contaminants from entering.


      NOTE
      When removing the pump, be careful not to damage any of the mating surfaces.



      Heater pipe bolt and temperature sensor wire from the thermostat housing
       
      Air intake pipe
       
      Water crossover assembly
       
      Hose from the turbo water feed line
       



      High pressure fuel lines and support pipe and hose at the fuel injection pump and junction block
       
      Fuel return hose from the fuel injection pump
       
      Y-junction banjo fitting from the junction block
       
      Bolts securing the fuel injection pump at the front cover and block
       



      Fuel injection pump from the block using 2 pry tools to work the pump from the block toward the rear of the engine, keeping the pump straight.

      Click image to see an enlarged view

      Fig. Diesel fuel injection pump-6.6L engines

       

    10.  
    11. Prepare the fuel pump as follows:
      1. Hold the fuel pump by the drive gear in a vise with copper jaw liners.
      2.  
      3. Loosen the gear nut until the nut is even with the end of the gear shaft.
      4.  
      5. Separate the pump and adapter by removing the 3 bolts and spacers.
      6.  
      7. Inspect the O-ring for damage on the pump adapter and replace if necessary. Lubricate the O-ring with clean engine oil.
      8.  
      9. Clean all mating surfaces.
      10.  
      11. Install the adapter on the pump
      12.  
      13. Using the bolts and spacers, reassemble the pump. Tighten the bolts to 15 ft. lbs. (20 Nm).
      14.  
      15. Install the gear and nut and tighten to 52 ft. lbs. (70 Nm).
      16.  

    12.  

    To install:

    1. Installation is the reverse of removal, noting the following tightening specifications:

      Fuel injection pump mounting bolts: 15 ft. lbs. (20 Nm)
       
      Y-junction banjo fitting: 11 ft. lbs. (15 Nm)
       
      High pressure fuel lines: 40 ft. lbs. (54 Nm)
       
      Heater pipe bracket and water crossover bolts: 15 ft. lbs. (20 Nm)
       
      Upper radiator hose mounting bolts: 89 inch lbs. (10 Nm)
       
      A/C and power steering pump bracket bolts: 34 ft. lbs. (46 Nm)
       

    2.  
    3. Refill the cooling system, then start the engine and check for leaks.
    4.  

    6.5L Engine
    1. Relieve the fuel system pressure.
    2.  
    3. Remove or disconnect the following:
      NOTE
      Do not engage the starter in order to rotate the engine with the injection pump removed. The pump driven gear could jam in the front housing resulting in a sheared crankshaft or camshaft gear key and possible valve train damage.



      Negative battery cables
       
      Intake manifold
       
      Fuel injection and inlet lines
       
      Cables wires, and hoses at the injection pump
       
      Fuel return line at the top of the injection pump
       
      Fuel feed line at the injection pump, if necessary
       
      Oil filler tube grommet
       

    4.  
    5. Scribe or paint a matchmark on the front cover and the injection pump flange.
    6.  
    7. Rotate the crankshaft by hand and remove the injection pump driven gear bolts, accessing the bolts through the oil filler neck hole.
    8.  
    9. Remove the injection pump-to-front cover attaching nuts. Remove the pump. Be sure to cap all open lines and nozzles in order to prevent system contamination and damage.
    10.  

    To install:

    Click image to see an enlarged view

    Fig. Align the pin on the pump hub with the slot in the driven gear, NOT into the hole in the gear-diesel engines

    1. Align the locating pin on the pump hub with the slot in the injection pump driven gear (the SLOT not the hole in the gear) At the same time, align the timing marks.
    2.  
    3. Attach the injection pump to the front cover. Torque the nuts to 30 ft. lbs. (40 Nm) checking the timing marks before tightening.
    4.  
    5. Install or connect the following:

      Driven gear-to-injection pump bolts and tighten to 20 ft. lbs. (27 Nm)
       
      Grommet and oil fill tube
       
      Air conditioning bracket, if applicable
       
      Fuel feed line. Torque to 20 ft. lbs. (27 Nm).
       
      Fuel return line to the pump, if removed
       
      Cables, wires and hoses previously removed
       
      Injector lines
       
      Intake manifold
       
      Negative battery cables
       

    6.  
    7. Start the engine and check for leaks.
    8.  

    1. Before servicing the vehicle, refer to the precautions in the beginning of this section.
    2.  
    3. Relieve the fuel system pressure.
    4.  
    5. Remove or disconnect the following:
      NOTE
      Do not engage the starter in order to rotate the engine with the injection pump removed. The pump driven gear could jam in the front housing resulting in a sheared crankshaft or camshaft gear key and possible valvetrain damage.



      Negative battery cables
       
      Intake manifold
       
      Fuel injection and inlet lines
       
      Cables wires, and hoses at the injection pump
       
      Fuel return line at the top of the injection pump
       
      Fuel feed line at the injection pump, if necessary
       
      Oil filler tube grommet
       

    6.  
    7. Scribe or paint a matchmark on the front cover and the injection pump flange.
    8.  
    9. Rotate the crankshaft by hand and remove the injection pump driven gear bolts, accessing the bolts through the oil filler neck hole.
    10.  
    11. Remove the injection pump-to-front cover attaching nuts. Remove the pump. Be sure to cap all open lines and nozzles in order to prevent system contamination and damage.
    12.  

    To install:

    Click image to see an enlarged view

    Fig. Align the pin on the pump hub with the slot in the driven gear, NOT into the hole in the gear-diesel engines

    1. Align the locating pin on the pump hub with the slot in the injection pump driven gear (the SLOT not the hole in the gear) At the same time, align the timing marks.
    2.  
    3. Attach the injection pump to the front cover. Torque the nuts to 30 ft. lbs. (40 Nm) checking the timing marks before tightening.
    4.  
    5. Install or connect the following:

      Driven gear-to-injection pump bolts. Torque the bolts to 20 ft. lbs. (25 Nm).
       
      Grommet and oil fill tube
       
      Air conditioning bracket. If applicable
       
      Fuel feed line. Torque to 20 ft. lbs. (25 Nm).
       
      Fuel return line to the pump, if removed
       
      Cables, wires and hoses previously removed
       
      Injector lines
       
      Intake manifold
       
      Negative battery cables
       

    6.  
    7. Start the engine and check for leaks.
    8.  

    1. Before servicing the vehicle, refer to the precautions in the beginning of this section.
    2.  
    3. Relieve the fuel system pressure.
    4.  
    5. Remove or disconnect the following:
      NOTE
      Do not engage the starter in order to rotate the engine with the injection pump removed. The pump driven gear could jam in the front housing resulting in a sheared crankshaft or camshaft gear key and possible valvetrain damage.



      Negative battery cables
       
      Intake manifold
       
      Fuel injection and inlet lines
       
      Cables wires, and hoses at the injection pump
       
      Fuel return line at the top of the injection pump
       
      Fuel feed line at the injection pump, if necessary
       
      Oil filler tube grommet
       

    6.  
    7. Scribe or paint a matchmark on the front cover and the injection pump flange.
    8.  
    9. Rotate the crankshaft by hand and remove the injection pump driven gear bolts, accessing the bolts through the oil filler neck hole.
    10.  
    11. Remove the injection pump-to-front cover attaching nuts. Remove the pump. Be sure to cap all open lines and nozzles in order to prevent system contamination and damage.
    12.  

    To install:

    Click image to see an enlarged view

    Fig. Align the pin on the pump hub with the slot in the driven gear, NOT into the hole in the gear-diesel engines

    1. Align the locating pin on the pump hub with the slot in the injection pump driven gear (the SLOT not the hole in the gear) At the same time, align the timing marks.
    2.  
    3. Attach the injection pump to the front cover. Torque the nuts to 30 ft. lbs. (40 Nm) checking the timing marks before tightening.
    4.  
    5. Install or connect the following:

      Driven gear-to-injection pump bolts. Torque the bolts to 20 ft. lbs. (25 Nm).
       
      Grommet and oil fill tube
       
      Air conditioning bracket. If applicable
       
      Fuel feed line. Torque to 20 ft. lbs. (25 Nm).
       
      Fuel return line to the pump, if removed
       
      Cables, wires and hoses previously removed
       
      Injector lines
       
      Intake manifold
       
      Negative battery cables
       

    6.  
    7. Start the engine and check for leaks.
    8.  

    6.6L Engine
    1. Drain the cooling system
    2.  
    3. Remove or disconnect the following:

      Negative battery cables
       
      Air intake duct. Cover the end to prevent dirt from entering
       
      Intake manifold cover
       
      Fuel fill cap in order to relieve the fuel pressure
       
      Fuel injection control module (FICM) electrical connectors
       
      Fuel injection control module
       
      Upper fan shroud
       
      Fan blade assembly
       
      Drive belt
       
      Bolt holding the positive battery cable junction box and bracket and position aside
       
      A/C compressor and power steering pump and position aside with the lines attached
       
      Oil dipstick tube
       
      A/C and power steering pump bracket
       
      Drive belt tensioner and bolt.
       
      Alternator
       
      Thermostat housing bracket, wiring and fuel test port and 2 nuts
       
      Positive Crankcase Ventilation (PCV) catch tank from the PCV bracket and the bolt below holding the lower line, then position aside
       
      Alternator bracket
       
      Turbo cooling hose return line clamp and hose
       
      Upper radiator hose at the outlet pipe. Remove the bracket and support the bracket at the valve cover and swing out of the way
       
      Bolt holding the wiring support bracket at the thermostat housing
       

    4.  
    5. Move the main wiring harness by disconnecting the following:
      1. The fuel pressure regulator connector on the fuel injection pump
      2.  
      3. Fuel injection control module connectors
      4.  

    6.  
    7. Flip the wire harness and harness tray towards the back and position aside.
    8.  
    9. Remove or disconnect the following:
      NOTE
      Cap all open fuel connections to prevent contaminants from entering.


      NOTE
      When removing the pump, be careful not to damage any of the mating surfaces.



      Heater pipe bolt and temperature sensor wire from the thermostat housing
       
      Air intake pipe
       
      Water crossover assembly
       
      Hose from the turbo water feed line
       



      High pressure fuel lines and support pipe and hose at the fuel injection pump and junction block
       
      Fuel return hose from the fuel injection pump
       
      Y-junction banjo fitting from the junction block
       
      Bolts securing the fuel injection pump at the front cover and block
       



      Fuel injection pump from the block using 2 pry tools to work the pump from the block toward the rear of the engine, keeping the pump straight.

      Click image to see an enlarged view

      Fig. Diesel fuel injection pump-6.6L engine

       

    10.  
    11. Prepare the fuel pump as follows:
      1. Hold the fuel pump by the drive gear in a vise with copper jaw liners.
      2.  
      3. Loosen the gear nut until the nut is even with the end of the gear shaft.
      4.  
      5. Separate the pump and adapter by removing the 3 bolts and spacers.
      6.  
      7. Inspect the O-ring for damage on the pump adapter and replace if necessary. Lubricate the O-ring with clean engine oil.
      8.  
      9. Clean all mating surfaces.
      10.  
      11. Install the adapter on the pump
      12.  
      13. Using the bolts and spacers, reassemble the pump. Tighten the bolts to 15 ft. lbs. (20 Nm).
      14.  
      15. Install the gear and nut and tighten to 52 ft. lbs. (70 Nm).
      16.  

    12.  

    To install:

    1. Installation is the reverse of removal, noting the following tightening specifications:

      Fuel injection pump mounting bolts: 15 ft. lbs. (20 Nm)
       
      Y-junction banjo fitting: 11 ft. lbs. (15 Nm)
       
      High pressure fuel lines: 40 ft. lbs. (54 Nm)
       
      Heater pipe bracket and water crossover bolts: 15 ft. lbs. (20 Nm)
       
      Upper radiator hose mounting bolts: 89 inch lbs. (10 Nm)
       
      A/C and power steering pump bracket bolts: 34 ft. lbs. (46 Nm)
       

    2.  
    3. Refill the cooling system, then start the engine and check for leaks.
    4.  

    1. Before servicing the vehicle, refer to the precautions in the beginning of this section.
    2.  
    3. Drain the cooling system
    4.  
    5. Remove or disconnect the following:

      Negative battery cables
       
      Air intake duct. Cover the end to prevent dirt from entering
       
      Upper fan shroud
       
      Fan blade assembly
       
      Drive belt
       
      Bolt holding the positive battery cable junction box and bracket and position aside
       
      A/C compressor and power steering pump and position aside with the lines attached
       
      Oil dipstick tube
       
      A/C and power steering pump bracket
       
      Alternator
       
      Thermostat housing bracket, wiring and fuel test port and 2 nuts
       
      Positive Crankcase Ventilation (PCV) catch tank from the PCV bracket and the bolt below holding the lower line, then position aside
       
      Alternator bracket
       
      Turbo cooling hose return line clamp and hose
       
      Upper radiator hose at the outlet pipe. Remove the bracket and support the bracket at the valve cover and swing out of the way
       
      Bolt holding the wiring support bracket at the thermostat housing
       

    6.  
    7. Move the main wiring harness by disconnecting:
      1. The fuel pressure regulator connector on the fuel injection pump
      2.  
      3. Fuel injection control module connectors
      4.  

    8.  
    9. Flip the wire harness and harness tray towards the back and position aside.
    10.  
    11. Remove or disconnect the following:
      NOTE
      Cap all open fuel connections to prevent contaminants from entering.


      NOTE
      When removing the pump, be careful not to damage any of the mating surfaces.



      Heater pipe bolt and temperature sensor wire from the thermostat housing
       
      Air intake pipe
       
      Water crossover assembly
       
      Hose from the turbo water feed line
       



      High pressure fuel lines and support pipe and hose at the fuel injection pump and junction block
       
      Fuel return hose from the fuel injection pump
       
      Y-junction banjo fitting from the junction block
       
      Bolts securing the fuel injection pump at the front cover and block
       



      Fuel injection pump from the block using 2 prytools to work the pump from the block toward the rear of the engine, keeping the pump straight.

      Click image to see an enlarged view

      Fig. Diesel fuel injection pump-6.6L engine

       

    12.  
    13. Prepare the fuel pump as follows:
      1. Hold the fuel pump by the drive gear in a vice with copper jaw liners.
      2.  
      3. Loosen the gear nut until the nut is even with the end of the gear shaft.
      4.  
      5. Separate the pump and adapter by removing the 3 bolts and spacers.
      6.  
      7. Inspect the O-ring for damage on the pump adapter and replace if necessary. Lubricate the O-ring with clean engine oil.
      8.  
      9. Clean all mating surfaces.
      10.  
      11. Install the adapter on the pump
      12.  
      13. Using the bolts and spacers, reassemble the pump. Tighten the bolts to 15 ft. lbs. (20 Nm).
      14.  
      15. Install the gear and nut and tighten to 52 ft. lbs. (70 Nm).
      16.  

    14.  

    To install:

    1. Installation is the reverse of removal, noting the following tightening specifications:

      Fuel injection pump mounting bolts: 15 ft. lbs. (20 Nm)
       
      Y-junction banjo fitting: 11 ft. lbs. (15 Nm)
       
      High pressure fuel lines: 40 ft. lbs. (54 Nm)
       
      Heater pipe bracket and water crossover bolts: 15 ft. lbs. (20 Nm)
       
      Upper radiator hose mounting bolts: 89 inch lbs. (10 Nm)
       
      A/C and power steering pump bracket bolts: 34 ft. lbs. (46 Nm)
       

    2.  
    3. Refill the cooling system, then start the engine and check for leaks.
    4.  

     
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