Engine Mechanical - 4.3L: Removal & Installation Chevrolet Silverado 1500 HD

Removal Procedure

Note. Refer to ENGINE MOUNTING NOTICE .

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1. From under the hood, remove the engine mount to engine mount bracket bolts, (right side shown, left side similar).
2. Raise and suitably support the vehicle. Refer to «JACKING AND LIFTING»(ref-188958) .
3. Remove the oil pan skid plate bolts and plate. NOTE: Refer to «ENGINE LIFTING NOTICE»(ref-175132-S39980754042005041500000) .
4. Using an adjustable jack on the square tab at the rear of the engine block, raise the engine.
5. Remove the engine mount bolts. (right side shown, left side similar).
6. Remove the engine mount.
7. If equipped and necessary, remove the engine mount side bracket bolts and bracket. (right side shown, left side similar).
8. Remove the engine mount bracket bolts.
9. Remove the engine mount bracket.

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1. Install the engine mount bracket. NOTE: Refer to «FASTENER NOTICE»(ref-175132-S17785009232005041500000) .
2. Install the engine mount bracket bolts. Tighten Tighten the engine mount bracket bolts to 75 N.m (55 lb ft).
3. Position the engine mount side bracket to the engine, if removed and equipped. (right side shown, left side similar).
4. Install the engine mount side bracket bolts. Tighten Tighten the engine mount side bracket bolts to 50 N.m (37 lb ft).
5. Install the engine mount. (right side shown, left side similar).
6. Install the engine mount bolts. Tighten Tighten the engine mount bolts to 50 N.m (37 lb ft).
7. Lower the engine.
8. Install the oil pan skid plate and bolts. Tighten Tighten the oil pan skid plate bolts to 20 N.m (15 lb ft).
9. Lower the vehicle.
10. Install the engine mount to engine mount bracket bolts. (right side shown, left side similar). Tighten Tighten the engine mount to engine mount bracket bolts to 65 N.m (48 lb ft).

Note. Refer to ENGINE MOUNTING NOTICE .

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1. From under the hood, remove the engine mount to engine mount bracket bolts. (left side shown, right side similar).
2. Raise and suitably support the vehicle. Refer to «JACKING AND LIFTING»(ref-188958) .
3. Remove the oil pan skid plate bolts and plate. NOTE: Refer to «ENGINE LIFTING NOTICE»(ref-175132-S39980754042005041500000) .
4. Using an adjustable jack on the square tab (left side shown) at the rear of the engine block, raise the engine. In order to access the square tab, remove the starter. (left side shown, right side similar). Refer to «STARTER MOTOR»(ref-168656-S31439200122004111300000) .
5. Remove the engine mount bolts.
6. Remove the engine mount.
7. If necessary remove the engine mount side bracket bolts and bracket.
8. Remove the engine mount bracket bolts.
9. Remove the engine mount bracket.

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1. Install the engine mount bracket. NOTE: Refer to «FASTENER NOTICE»(ref-175132-S17785009232005041500000) .
2. Install the engine mount bracket bolts. Tighten Tighten the engine mount bracket bolts to 75 N.m (55 lb ft).
3. Position the engine mount side bracket to the engine, if removed.
4. Install the engine mount side bracket bolts. Tighten Tighten the engine mount side bracket bolts to 50 N.m (37 lb ft).
5. Install the engine mount.
6. Install the engine mount bolts. Tighten Tighten the engine mount bolts to 50 N.m (37 lb ft).
7. Lower the engine.
8. Install the starter. Refer to «STARTER MOTOR»(ref-168656-S31439200122004111300000) .
9. Install the oil pan skid plate and bolts. Tighten Tighten the oil pan skid plate bolts to 20 N.m 15 lb ft).
10. Lower the vehicle.
11. Install the engine mount to engine mount bracket bolts. Tighten Tighten the engine mount to engine mount bracket bolts to 65 N.m (48 lb ft).

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1. Remove the fuel pipes/hoses. Refer to «FUEL HOSES & PIPES»(ref-159093-S06507509882003111200000) .
2. Disconnect the cruise control cable from the throttle lever, if equipped.
3. Remove the cruise control cable from the accelerator control cable bracket, if equipped.
4. Remove the accelerator cable from the throttle body lever.
5. Remove the accelerator cable from the accelerator control cable bracket.
6. Disconnect the following electrical connectors: The air conditioning (A/C) compressor clutch (1), if equipped The A/C pressure switch (4), if equipped
7. Remove the engine wiring harness clip (3) from the accelerator control cable bracket.
8. Remove the accelerator control cable bracket nuts.
9. Remove the accelerator control cable bracket with the cables attached, from the throttle body.
10. Reposition and secure the bracket and cables out of the way.
11. Disconnect the following electrical connectors: The throttle position (TP) sensor (1) The idle air control (IAC) motor (2) The control port injector module (3)
12. Remove the engine wiring harness clip bolt (4).
13. Disconnect the following electrical connectors: The evaporative emission (EVAP) canister purge solenoid valve (1) The manifold absolute pressure (MAP) sensor (2)
14. Disconnect the EVAP canister harness from the purge solenoid valve.
15. Remove the engine wiring harness bracket nuts.
16. Remove the engine wiring harness bracket.
17. Remove the engine wiring harness ground nut and ground wire (4) from the rear of the right cylinder head.
18. Remove the engine wiring harness rear bracket nut at the EVAP canister purge solenoid valve.
19. Remove the stud holding the engine wiring harness bracket.
20. Reposition the engine wiring harness with the bracket aside.
21. Remove the PCV valve hose from the valve and rocker cover.
22. Disconnect the power brake booster vacuum hose from the vacuum fitting.
23. Remove the accelerator cable bracket nuts.
24. Remove the accelerator cable bracket.
25. Remove the intake manifold-upper studs.
26. Remove the front two throttle body studs.
27. Remove the intake manifold-upper.
28. Remove and discard the intake manifold-upper gasket.
29. Remove and discard the O-ring seal from the fuel meter body.
30. If required, remove the power brake booster vacuum fitting.
31. Remove and discard the O-ring seal.
32. If required, remove the PCV valve cover.
33. Remove and discard the O-ring seal.
34. If required, remove the rear throttle body stud.
35. Remove the throttle body.
36. Remove and discard the throttle body gasket.
37. If required, remove the MAP sensor.
38. Remove and discard the MAP sensor seal.
39. If required, remove the EVAP canister purge solenoid valve studs.
40. Remove the purge solenoid valve.
41. Clean and inspect the intake manifold-upper, if necessary. Refer to «Intake Manifold Cleaning and Inspection»(ref-188990-S04885303762005091300000) .

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1. If required, install the purge solenoid valve. NOTE: Refer to «FASTENER NOTICE»(ref-175132-S17785009232005041500000) .
2. Install the EVAP canister purge solenoid valve studs. If reusing the old studs, apply threadlock GM P/N 12345382, (Canadian P/N 10953489), or equivalent to the threads. Tighten Tighten the studs to 10 N.m (89 lb in).
3. If required, install a NEW MAP sensor seal. Apply a small drop of clean engine oil to the seal.
4. Install the MAP sensor.
5. If required, install a NEW throttle body gasket.
6. Install the throttle body.
7. Install the rear throttle body stud. If reusing the old stud, apply threadlock GM P/N 12345382, (Canadian P/N 10953489), or equivalent to the threads. Tighten Tighten the stud to 9 N.m (80 lb in).
8. If required, install a NEW O-ring seal to the PCV cover. Apply clean engine oil to the seal.
9. Install the PCV valve cover.
10. If required, install a NEW O-ring seal. Apply clean engine oil to the seal.
11. Install the power brake booster vacuum fitting.
12. Install a NEW O-ring seal to the fuel meter body.
13. Install a NEW upper intake manifold gasket.
14. Install the intake manifold-upper.
15. If reusing the old throttle body/intake manifold studs, apply threadlock GM P/N 12345382, (Canadian P/N 10953489), or equivalent to the threads.
16. Install the front two throttle body studs.
17. Install the intake manifold-upper studs. Tighten Tighten the studs to 9 N.m (80 lb in).
18. Install the accelerator cable bracket.
19. Install the accelerator cable bracket nuts. Tighten Tighten the nuts to 12 N.m (106 lb in).
20. Connect the power brake booster vacuum hose to the vacuum fitting.
21. Install the PCV valve hose to the valve cover and rocker cover.
22. Position the engine wiring harness and bracket.
23. Install the engine wiring harness bracket stud. Tighten Tighten the stud to 25 N.m (18 lb ft).
24. Install the engine wiring harness rear bracket nut at the EVAP canister purge solenoid valve. Tighten Tighten the nut to 9 N.m (80 lb in).
25. Install the engine wiring harness ground nut and ground wire (4) to the rear of the right cylinder head. Tighten Tighten the nut to 16 N.m (12 lb ft).
26. Install the engine wiring harness bracket.
27. Install the engine wiring harness bracket nuts. Tighten Tighten the nuts to 12 N.m (106 lb in).
28. Connect the EVAP canister harness to the purge solenoid valve.
29. Connect the following electrical connectors: The EVAP canister purge solenoid valve (1) The MAP sensor (2)
30. Connect the following electrical connectors: The TP sensor (1) The IAC motor (2) The control port injector module (3)
31. Install the engine wiring harness clip bolt (4). Tighten Tighten the bolt to 9 N.m (80 lb in).
32. Position the bracket and cables.
33. Install the accelerator control cable bracket with the cables attached, to the throttle body.
34. Install the accelerator control cable bracket nuts. Tighten Tighten the nuts to 9 N.m (80 lb in).
35. Connect the following electrical connectors: The A/C compressor clutch (1), if equipped The A/C pressure switch (4), if equipped
36. Install the engine wiring harness clip (3) to the accelerator control cable bracket.
37. Install the accelerator cable to the accelerator control cable bracket.
38. Install the accelerator cable to the throttle body lever.
39. Install the cruise control cable to the accelerator control cable bracket, if equipped.
40. Connect the cruise control cable to the throttle lever, if equipped.
41. Install the fuel pipes/hoses. Refer to «FUEL HOSES & PIPES»(ref-159093-S06507509882003111200000) .

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1. Drain the cooling system. Refer to «DRAINING AND FILLING COOLING SYSTEM»(ref-188992-S10584397332005091300000) .
2. Remove the fuel pipes/hoses. Refer to «FUEL HOSES & PIPES»(ref-159093-S06507509882003111200000) .
3. Remove the distributor. Refer to «DISTRIBUTOR»(ref-157348-S39798927472003081100000) .
4. Disconnect the evaporative emission (EVAP) canister harness from the purge solenoid valve.
5. Remove the heater hose clamp (1).
6. Open the heater outlet hose clamp and remove the hose from the intake manifold.
7. Open the heater inlet hose clamp and remove the hose from the water pump.
8. Reposition the heater inlet and outlet hoses.
9. Disconnect the cruise control cable from the throttle body lever, if equipped.
10. Remove the cruise control cable from the accelerator control cable bracket, if equipped.
11. Remove the accelerator cable from the throttle body lever.
12. Remove the accelerator cable from the accelerator control cable bracket.
13. Disconnect the following electrical connectors: The air conditioning (A/C) compressor clutch (1), if equipped The A/C pressure switch (4), if equipped
14. Remove the engine wiring harness clip (3) from the accelerator control cable bracket.
15. Remove the accelerator control cable bracket nuts.
16. Remove the accelerator control cable bracket with the cables attached, from the throttle body.
17. Reposition and secure the bracket and cables out of the way.
18. Disconnect the following electrical connectors: The throttle position (TP) sensor (1) The idle air control (IAC) motor (2) The control port injector module (3)
19. Remove the engine wiring harness clip bolt (4).
20. Disconnect the following electrical connectors: The evaporative emission (EVAP) canister purge solenoid valve (1) The manifold absolute pressure (MAP) sensor (2)
21. Remove the engine wiring harness bracket nuts.
22. Remove the engine wiring harness bracket.
23. Remove the engine wiring harness ground nut and ground wire (4) from the rear of the right cylinder head.
24. Remove the engine wiring harness rear bracket nut at the EVAP canister purge solenoid valve.
25. Remove the stud holding the engine wiring harness bracket.
26. Reposition the engine wiring harness with the bracket aside.
27. Remove the PCV valve hose from the valve cover and rocker cover.
28. Disconnect the power brake booster vacuum hose from the vacuum fitting.
29. Reposition the radiator inlet hose clamps.
30. Remove the radiator inlet hose from the thermostat housing.
31. Reposition the water pump inlet hose clamps.
32. Remove the water pump inlet hose.
33. In order to remove the front intake manifold bolt, perform the following: 33.1. Remove the drive belt. Refer to «Drive Belt Replacement»(ref-188990-S25259374762005091300000) . 33.2. Loosen the power steering (P/S) pump rear bracket nut. 33.3. Remove the P/S pump rear bracket front nut. 33.4. Remove the bolts and the nut for the P/S pump bracket. 33.5. Leave the A/C compressor, if equipped, and the P/S pump on the bracket. 33.6. Slide the P/S pump bracket forward to access the front intake manifold bolt.
34. Remove the intake manifold-lower bolts.
35. Remove the intake manifold.
36. Remove and discard the intake manifold gaskets.
37. Clean and inspect the intake manifold-lower, if necessary. Refer to «Intake Manifold Cleaning and Inspection»(ref-188990-S04885303762005091300000) .

Installation Procedure

Note. Apply the proper amount of the sealant when assembling this component. Excessive use of the sealant can prohibit the component from sealing properly. A component that is not sealed properly can leak leading to extensive engine damage.

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1. Apply a 4.0 mm (0.157 in) patch of adhesive GM P/N 12346141, (Canadian P/N 10953433), or equivalent to the cylinder head side of the intake manifold gasket at each end. IMPORTANT: The intake manifold gasket must be installed while the adhesive is still wet to the touch.
2. Install the intake manifold gasket onto the cylinder head. Use the gasket locating pins in order to properly seat the gasket. IMPORTANT: The intake manifold must be installed and the fasteners tightened while the adhesive is still wet to the touch.
3. Apply a 5 mm (0.197 in) bead of adhesive GM P/N 12346141, (Canadian P/N 10953433), or equivalent to the front top of the engine block.
4. Extend the adhesive bead 13 mm (0.50 in) up onto each intake manifold gasket.
5. Apply a 5 mm (0.197 in) bead of adhesive GM P/N 12346141, (Canadian P/N 10953433), or equivalent to the rear top of the engine block.
6. Extend the adhesive bead 13 mm (0.50 in) up onto each intake manifold gasket.
7. Install the intake manifold.
8. If reusing the old fasteners, apply threadlock GM P/N 12345382, (Canadian P/N 10953489), or equivalent to the threads of the intake manifold-lower bolts.
9. Install the intake manifold-lower bolts. NOTE: Proper lower intake manifold fastener tightening sequence and torque is critical. Always follow the tightening sequence, and torque the intake manifold bolts using the 3 step method. Failing to do so may distort the crankshaft bearing bore alignment and cause damage to the crankshaft bearings. NOTE: Refer to «FASTENER NOTICE»(ref-175132-S17785009232005041500000) .
10. Tighten the intake manifold-lower bolts in the sequence shown. Tighten 10.1. Tighten the bolts a first pass to 3 N.m (27 lb in). 10.2. Tighten the bolts a second pass to 12 N.m (106 lb in). 10.3. Tighten the bolts a final pass to 15 N.m (11 lb ft).
11. Slide the P/S pump bracket rearward.
12. Install the bolts and the nut for the P/S pump bracket.
13. Install the P/S pump rear bracket front nut.
14. Tighten the P/S pump rear bracket nut. Tighten Tighten the bolts and nuts to 41 N.m (30 lb ft).
15. Install the drive belt. Refer to «Drive Belt Replacement»(ref-188990-S25259374762005091300000) .
16. Install the water pump inlet hose.
17. Position the water pump inlet hose clamps.
18. Install the radiator inlet hose to the thermostat housing.
19. Position the radiator inlet hose clamps.
20. Connect the power brake booster vacuum hose to the vacuum fitting.
21. Install the PCV valve hose to the valve cover and rocker cover.
22. Position the engine wiring harness and bracket.
23. Install the engine wiring harness bracket stud. Tighten Tighten the stud to 25 N.m (18 lb ft).
24. Install the engine wiring harness rear bracket nut at the EVAP canister purge solenoid valve. Tighten Tighten the nut to 9 N.m (80 lb in).
25. Install the engine wiring harness ground nut and ground wire (4) to the rear of the right cylinder head. Tighten Tighten the nut to 16 N.m (12 lb ft).
26. Install the engine wiring harness bracket.
27. Install the engine wiring harness bracket nuts. Tighten Tighten the nuts to 12 N.m (106 lb in).
28. Connect the EVAP canister harness to the purge solenoid valve.
29. Connect the following electrical connectors: The EVAP canister purge solenoid valve (1) The MAP sensor (2)
30. Connect the following electrical connectors: The TP sensor (1) The IAC motor (2) The control port injector module (3)
31. Install the engine wiring harness clip bolt (4). Tighten Tighten the bolt to 9 N.m (80 lb in).
32. Position the bracket and cables.
33. Install the accelerator control cable bracket with the cables attached, to the throttle body.
34. Install the accelerator control cable bracket nuts. Tighten Tighten the nuts to 9 N.m (80 lb in).
35. Connect the following electrical connectors: The A/C compressor clutch (1), if equipped The A/C pressure switch (4), if equipped
36. Install the engine wiring harness clip (3) to the accelerator control cable bracket.
37. Install the accelerator cable to the accelerator control cable bracket.
38. Install the accelerator cable to the throttle body lever.
39. Install the cruise control cable to the accelerator control cable bracket, if equipped.
40. Connect the cruise control cable to the throttle lever, if equipped.
41. Position the heater inlet and outlet hoses.
42. Open the heater inlet hose clamp and install the hose to the water pump.
43. Open the heater out let hose clamp and install the hose to the intake manifold.
44. Install the heater hose clamp (1).
45. Install the fuel pipes/hoses. Refer to «FUEL HOSES & PIPES»(ref-159093-S06507509882003111200000) .
46. Install the distributor. Refer to «DISTRIBUTOR»(ref-157348-S39798927472003081100000) .
47. Fill the cooling system. Refer to «DRAINING AND FILLING COOLING SYSTEM»(ref-188992-S10584397332005091300000) .

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1. Remove the engine wiring harness bracket nuts.
2. Remove the engine wiring harness bracket.
3. Remove the engine wiring harness clip bolt (4).
4. Disconnect the engine coolant temperature (ECT) sensor electrical connector (5).
5. Reposition the engine wiring harness and bracket.
6. Disconnect the power brake booster vacuum hose from the vacuum fitting.
7. Remove the positive crankcase ventilation (PCV) valve hose from the valve cover and rocker cover.
8. Remove the rocker arm cover bolts.
9. Remove and discard the rocker arm cover bolt grommets, if necessary.
10. Remove the rocker arm cover.
11. Remove and discard the rocker arm cover gasket.
12. Clean and inspect the rocker arm cover, if necessary. Refer to «Valve Rocker Arm Cover Cleaning and Inspection»(ref-188990-S42715069062005091300000) .

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1. Install a NEW rocker arm cover gasket to the cover.
2. Install NEW rocker arm cover bolt grommets to the cover, if necessary.
3. Install the rocker arm cover. NOTE: Refer to «FASTENER NOTICE»(ref-175132-S17785009232005041500000) .
4. Install the rocker arm cover bolts. Tighten Tighten the bolts to 12 N.m (106 lb in).
5. Install the PCV valve hose to the valve cover and rocker cover.
6. Connect the power brake booster vacuum hose to the vacuum fitting.
7. Position the engine wiring harness and bracket.
8. Connect the ECT sensor electrical connector (5).
9. Install the engine wiring harness clip bolt (4). Tighten Tighten the bolt to 9 N.m (80 lb in).
10. Install the engine wiring harness bracket.
11. Install the engine wiring harness bracket nuts. Tighten Tighten the nuts to 12 N.m (106 lb in).

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1. Loosen the air cleaner outlet duct clamp at the mass airflow/intake air temperature (MAF/IAT) 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 releases from the lip on the throttle body.
5. Remove the heater outlet hose from the clip.
6. Move and secure the heater hoses out of the way.
7. Disconnect the following electrical connectors: The ignition coil (1) The ignition coil drive (2) The generator (3)
8. Disconnect the engine wiring harness clips.
9. Reposition the engine wiring harness.
10. Remove the rocker arm cover bolts.
11. Remove and discard the rocker arm cover bolt grommets, if necessary.
12. Remove the rocker arm cover.
13. Remove and discard the rocker arm cover gasket.
14. Clean and inspect the rocker arm cover, if necessary. Refer to «Valve Rocker Arm Cover Cleaning and Inspection»(ref-188990-S42715069062005091300000) .

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1. Install a NEW rocker arm cover gasket.
2. Install NEW rocker arm cover bolt grommets, if necessary.
3. Install the rocker arm cover. NOTE: Refer to «FASTENER NOTICE»(ref-175132-S17785009232005041500000) .
4. Install the rocker arm cover bolts. Tighten Tighten the bolts to 12 N.m (106 lb in).
5. Position the engine wiring harness.
6. Connect the engine wiring harness clips.
7. Connect the following electrical connectors: The ignition coil (1) The ignition coil drive (2) The generator (3)
8. Position the heater hoses.
9. Install the heater outlet to the hose clip.
10. 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.
11. Install the air cleaner adapter nut.
12. Install the positive crankcase ventilation (PCV) hose.
13. Tighten the air cleaner outlet duct clamp at the MAF/IAT sensor.

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1. Remove the rocker arm cover. Refer to «Valve Rocker Arm Cover Replacement - Left»(ref-188990-S32770270612005091300000) or «Valve Rocker Arm Cover Replacement - Right»(ref-188990-S12943198792005091300000) .
2. Remove the rocker arms.
3. Remove the rocker arm supports.
4. Remove the pushrods.
5. Clean and inspect the rocker arms and/or pushrods, if necessary. Refer to «Valve Rocker Arm and Push Rods Cleaning and Inspection»(ref-188990-S20974581082005091300000) .

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1. Install the pushrods. IMPORTANT: Be sure that the arrow on the rocker arm support is in the up position.
2. Install the rocker arm supports.
3. Apply lubricant GM P/N 12345501, (Canadian P/N 992704), or equivalent to the following rocker arm contact surfaces: Pushrod socket (1) Roller pivot (2) Valve stem tip (3) NOTE: Refer to «FASTENER NOTICE»(ref-175132-S17785009232005041500000) .
4. Install the rocker arms as follows: 4.1. Finger start the bolt at location (1) 4.2. Finger start the bolt at location (2) 4.3. Finger start the bolt at location (3) 4.4. Finger start the remaining rocker arm bolts
5. Rotate the crankshaft balancer to position the crankshaft balancer alignment mark (1) 57-63 degrees clockwise or counterclockwise from the engine front cover alignment tab (2). IMPORTANT: Once the rocker arms are installed and properly torqued, no additional valve lash adjustment is required.
6. Tighten the rocker arm bolts. Tighten Tighten bolts to 30 N.m (22 lb ft).
7. Install the rocker arm cover. Refer to «Valve Rocker Arm Cover Replacement - Left»(ref-188990-S32770270612005091300000) or «Valve Rocker Arm Cover Replacement - Right»(ref-188990-S12943198792005091300000) .

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1. Assemble the valve into the proper valve guide.
2. Select the proper valve stem oil seal for the specific valve guide.
3. Lubricate the valve stem oil seal and the outside diameter of the valve guide with clean engine oil.
4. Assemble the valve stem oil seal onto the valve stem.
5. Using the J 42073 , install the valve stem oil seal onto the valve guide. 5.1. Tap the valve stem oil seal onto the valve guide until the J 42073 bottoms against the valve spring seat. 5.2. Inspect the valve stem oil seal. The valve stem oil seal should not be bottomed against the valve guide. There should be a 1-2 mm (0.03937-0.07874 in) gap between the bottom edge of the valve stem oil seal and the valve guide.
6. Install the valve spring (3).
7. Install the valve spring cap (2) onto the valve spring (3), over the valve stem. CAUTION: Compressed valve springs have high tension against the valve spring compressor. Valve springs that are not properly compressed by or released from the valve spring compressor can be ejected from the valve spring compressor with intense force. Use care when compressing or releasing the valve spring with the valve spring compressor and when removing or installing the valve stem keys. Failing to use care may cause personal injury.
8. Use the J 5892-D in order to compress the valve spring. Hook the slotted end of J 5892-D under the washer on the valve rocker arm bolt.
9. Apply steady pressure on the valve spring cap until the valve keys are accessible. NOTE: Completely engage the J 38606 jaws on the valve spring. The J 38606 may slip off and scratch the valve spring. Replace the valve spring if the valve spring becomes scratch.
10. Use the J 38606 if the clearance does not permit use of the J 5892-D .
11. Install the valve stem O-ring seal.
12. Install the valve stem keys. Use grease in order to hold the valve stem keys in place.
13. Carefully release the valve spring pressure, making sure the valve stem keys stay in place. NOTE: The valve stem keys must correctly seat in the valve spring cap. Engine damage may occur by not installing properly.
14. Remove the J 5892-D or the J 38606 . 14.1. Look to ensure that the valve stem keys seat properly in the upper groove of the valve stem. 14.2. Tap the end of the valve stem with a plastic faced hammer in order to seat the valve stem keys, if necessary.
15. Remove the J 22794.
16. Install the spark plugs. Refer to «SPARK PLUG»(ref-157348-S39708791382003090200000) .
17. Install the valve rocker arms. Refer to «Valve Rocker Arm and Push Rod Replacement»(ref-188990-S34861579492005091300000) .

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1. Apply lubricant GM P/N 12345501, (Canadian P/N 992704), or equivalent to the lifter rollers. IMPORTANT: If reusing the lifters, install the lifters to their original positions.
2. Install the lifters. NOTE: Refer to «FASTENER NOTICE»(ref-175132-S17785009232005041500000) .
3. Install the lifter pushrod guides. Tighten Tighten the bolts to 16 N.m (12 lb ft).
4. Install the pushrods. Refer to «Valve Rocker Arm and Push Rod Replacement»(ref-188990-S34861579492005091300000) .
5. Install the intake manifold. Refer to «Intake Manifold Replacement - Lower»(ref-188990-S10715529002005091300000) .

Note. Failure to properly align the crankshaft position sensor reluctor ring may result in component damage and effect OBD II system performance.

Scheme 311

1. Install the CKP sensor reluctor ring. 1.1. Align the keyway on the CKP sensor reluctor ring with the key in the crankshaft. 1.2. Using J 5590 , push the CKP sensor reluctor ring onto the crankshaft until completely seated against the crankshaft sprocket.
2. Install the engine front cover. Refer to «Engine Front Cover Replacement»(ref-188990-S15972686922005091300000) .

Note. In order to rotate the engine install a bolt with the same threads as the crankshaft, but do not use the crankshaft balancer bolt or a bolt longer than 1 inch, in the crankshaft. Failing to do so will cause damage to the bolt threads and the crankshaft threaded hole when removing the bolt.

Scheme 312

Scheme 313

Scheme 314

Scheme 315

Scheme 316

1. Remove the crankshaft position (CKP) sensor reluctor ring. Refer to «Crankshaft Position (CKP) Reluctor Ring Replacement»(ref-188990-S24092040392005091300000) .
2. Install a 7/16-20 x 1 inch bolt into the end of the crankshaft. NOTE: Align the timing marks before removing the timing chain. If it is necessary to turn either the camshaft or the crankshaft with the timing chain removed, loosen or remove the valve rocker arms. Turning either the crankshaft or camshaft with the timing chain removed may cause the pistons to contact the valves, resulting in damage.
3. Rotate the crankshaft until: 3.1. The timing marks on both sprockets line up. 3.2. The number four cylinder is at top dead center (TDC) of the compression stroke.
4. Remove the camshaft sprocket bolts.
5. Remove the camshaft sprocket and the camshaft timing chain.
6. Using J 5825-A and an open end wrench, remove the crankshaft sprocket.
7. Remove the crankshaft balancer key.
8. Clean and inspect the timing chain and sprockets, if necessary. Refer to «Timing Chain and Sprockets Cleaning and Inspection»(ref-188990-S13353801152005091300000) .

Scheme 317

Scheme 318

Scheme 319

Scheme 320

Scheme 321

1. Install the key into the crankshaft keyway. The crankshaft balancer key should be parallel to the crankshaft or with a slight incline.
2. Align the keyway of the crankshaft sprocket with the crankshaft balancer key.
3. Using J 5590 , install the crankshaft sprocket. IMPORTANT: Install the camshaft sprocket with the alignment mark at the 6 o'clock position.
4. Install the camshaft sprocket and the camshaft timing chain.
5. Ensure that the crankshaft sprocket is aligned at the 12 o'clock position and camshaft sprocket is aligned at the 6 o'clock position. NOTE: Refer to «FASTENER NOTICE»(ref-175132-S17785009232005041500000) . IMPORTANT: Do not use a hammer to install the camshaft sprocket onto the camshaft. To do so may dislodge the expansion cup plug.
6. Install camshaft sprocket bolts. Tighten Tighten the bolts to 25 N.m (18 lb ft).
7. Remove the bolt that was installed in the end of the crankshaft.
8. Install the CKP sensor reluctor ring. Refer to «Crankshaft Position (CKP) Reluctor Ring Replacement»(ref-188990-S24092040392005091300000) .

Scheme 322

Scheme 323

Scheme 324

Scheme 325

Scheme 326

Scheme 327

Scheme 328

Scheme 329

1. Apply clean engine oil to the balance shaft front bearing.
2. Using J 36996 and J 8092 , install the balance shaft. NOTE: Refer to «FASTENER NOTICE»(ref-175132-S17785009232005041500000) .
3. Install the balance shaft retainer and bolts. Tighten Tighten the bolts to 12 N.m (106 lb in).
4. Install the balance shaft driven gear.
5. If reusing the fastener, apply threadlock GM P/N 12345382, (Canadian P/N 10953489), or equivalent to the threads of the balance shaft driven gear bolt.
6. Install the balance shaft driven gear bolt. 6.1. Use a wrench to secure the balance shaft. Place the wrench onto the balance shaft near to the balance shaft front bearing. 6.2. Install the balance shaft driven gear bolt. Tighten 6.2.1. Tighten the bolt a first pass to 20 N.m (15 lb ft). 6.2.2. Tighten the bolt a final pass using the J 36660-A an additional 35 degrees.
7. Remove the wrench from the balance shaft.
8. Rotate the balance shaft by hand in order to ensure that there is clearance between the balance shaft and the valve lifter pushrod guide. If the balance shaft does not rotate freely, check to ensure that the retaining ring on the balance shaft front bearing is seated on the case.
9. Install the balance shaft drive gear. DO NOT install the camshaft sprocket bolts at this time.
10. Rotate the camshaft so that the timing mark on the balance shaft drive gear is in the 12 o'clock position.
11. Remove the balance shaft drive gear.
12. Rotate the balance shaft so that the timing mark on the balance shaft driven gear is in the 6 o'clock position.
13. Position the balance shaft drive gear onto the engine camshaft.
14. Look to ensure that the balance shaft drive gear and the balance shaft driven gear timing marks are aligned.
15. Install the timing chain and the camshaft sprocket. Refer to «Timing Chain and Sprockets Replacement»(ref-188990-S23294840662005091300000) .
16. Install the valve lifter pushrod guide. Refer to «Valve Lifter Replacement»(ref-188990-S17616145452005091300000) .
17. Install the A/C condenser. Refer to «CONDENSER REPLACEMENT»(ref-188960-S27462254692005091100000) .
18. Install the radiator. Refer to «RADIATOR REPLACEMENT»(ref-188992-S41168071262005091300000) .

Scheme 330

1. Remove the balance shaft. Refer to «Balance Shaft Replacement»(ref-188990-S00228576532005091300000) .
2. Using J 26941 and the J 38834 , remove the balance shaft rear bearing. 2.1. Install the J 26941 legs behind the balance shaft rear bearing and secure. 2.2. Install the J 38834-1 with the short threaded end through the balance shaft bore in the front of the engine block. 2.3. Install J 38834-1 into the J 26941 . 2.4. Slide the J 38834-2 onto the J 38834-1 and into the balance shaft bore of the engine block. 2.5. Install the J 38834 bearing, washer, and nut onto the J 38834-1. 2.6. Using a wrench, secure the J 38834-1, and then rotate the J 38834 nut clockwise until the balance shaft rear bearing is removed from the engine block. 2.7. Remove the J 26941 from the balance shaft rear bearing.
3. Discard the balance shaft rear bearing.

Scheme 331

1. Using J 38834 , install the balance shaft rear bearing. 1.1. Install the J 38834-3 onto the short threaded end of the J 38834-1. 1.2. Install the J 38834 nut, the washer, and the bearing on the long threaded end of the J 38834-1. 1.3. Install the J 38834-2 onto the J 38834-1 so that the smaller diameter of the J 38834-2 will be facing the front of the engine block. 1.4. Install the J 38834-2 on the inside of the balance shaft front bearing bore. 1.5. Lubricate the NEW balance shaft rear bearing with clean engine oil. 1.6. Install the balance shaft rear bearing onto the J 38834-2. 1.7. Align the balance shaft rear bearing for installation. 1.8. Using a wrench, secure the J 38834-1 into place. 1.9. Rotate the J 38834 nut until the balance shaft rear bearing is properly and completely pushed into the balance shaft rear bearing bore.
2. Remove the J 38834 .
3. Install the balance shaft. Refer to «Balance Shaft Replacement»(ref-188990-S00228576532005091300000) .

Scheme 332

Scheme 333

Scheme 334

1. Remove the radiator. Refer to «RADIATOR REPLACEMENT»(ref-188992-S41168071262005091300000) .
2. Remove the air conditioning (A/C) condenser. Refer to «CONDENSER REPLACEMENT»(ref-188960-S27462254692005091100000) .
3. Remove the lifters. Refer to «Valve Lifter Replacement»(ref-188990-S17616145452005091300000) .
4. Remove the timing chain and the camshaft sprocket. Refer to «Timing Chain and Sprockets Replacement»(ref-188990-S23294840662005091300000) .
5. Remove the balance shaft drive gear.
6. Remove the camshaft retainer bolts and retainer. NOTE: All camshaft journals are the same diameter, so care must be used in removing or installing the camshaft to avoid damage to the camshaft bearings.
7. Remove the engine camshaft. 7.1. Install the three 5/16-18 x 4.0 inch bolts into the engine camshaft front bolt holes. 7.2. Using the bolts as a handle, carefully rotate and pull the engine camshaft out of the camshaft bearings. 7.3. Remove the bolts from the front of the engine camshaft. 7.4. Clean and inspect the camshaft and/or bearings, if necessary. Refer to «Camshaft and Bearings Cleaning and Inspection»(ref-188990-S11949042142005091300000) .

1. Change the engine oil and filter.
2. Add engine oil supplement GM P/N 1052367, (Canadian P/N 992869), or equivalent to the engine oil.

Scheme 335

Scheme 336

1. Apply lubricant GM P/N 12345501, (Canadian P/N 992704), or equivalent, or engine oil supplement GM P/N 1052367, (Canadian P/N 992869), or equivalent to the following components: The engine camshaft lobes The camshaft bearing journals The camshaft bearings
2. Install three 5/16-18 x 4.0 inch bolts into the engine camshaft front bolt holes. NOTE: All camshaft journals are the same diameter, so care must be used in removing or installing the camshaft to avoid damage to the camshaft bearings.
3. Using the bolts as a handle, install the engine camshaft.
4. Remove the 3 bolts from the front of the engine camshaft. NOTE: Refer to «FASTENER NOTICE»(ref-175132-S17785009232005041500000) .
5. If reusing the fasteners, apply threadlock GM P/N 12345382 or equivalent to the threads of the camshaft retainer bolts.
6. Install the camshaft retainer and bolts. Tighten Tighten the bolts to 12 N.m (106 lb in).
7. Install the balance shaft drive gear. Refer to «Balance Shaft Installation»(ref-188990-S27839102872005091300000) , for alignment of the balance shaft drive gear and the driven gear.
8. Install the timing chain and camshaft sprocket. Refer to «Timing Chain and Sprockets Replacement»(ref-188990-S23294840662005091300000) .
9. Install the lifters. Refer to «Valve Lifter Replacement»(ref-188990-S17616145452005091300000) .
10. Install the A/C condenser. Refer to «CONDENSER REPLACEMENT»(ref-188960-S27462254692005091100000) .
11. Install the radiator. Refer to «RADIATOR REPLACEMENT»(ref-188992-S41168071262005091300000) .

Scheme 337

Scheme 338

1. Raise and suitably support the vehicle. Refer to «JACKING AND LIFTING»(ref-188958) .
2. Remove the oil pan drain plug and drain the oil into a suitable container.
3. Remove the oil filter.
4. Remove the oil filter adapter.

Note. Refer to FASTENER NOTICE .

Scheme 339

Scheme 340

1. Install the oil pan drain plug into the drain pan. Tighten Tighten the plug to 25 N.m (18 lb ft).
2. Install the oil filter adapter. Tighten Tighten the adapter to 55 N.m (41 lb ft).
3. Install the oil filter Tighten Tighten the filter to 30 N.m (22 lb ft).
4. Lower the vehicle.
5. Fill the engine with the proper quantity and quality of engine oil.

Scheme 341

Scheme 342

1. Raise and suitably support the vehicle. Refer to «JACKING AND LIFTING»(ref-188958) .
2. Position a suitable container under the vehicle to catch the oil.
3. Remove the oil filter.
4. Using a suitable prying tool, remove the oil filter bypass valve.
5. Clean and inspect the valve bore for damage.

Scheme 343

Scheme 344

1. Install a NEW oil filter bypass valve using the following procedure: 1.1. Use a brass drift that is the same diameter as the outside diameter of the oil filter bypass valve. 1.2. Install the oil filter bypass valve into the oil gallery bore until slightly below flush with the surface of the engine block. 1.3. Using a pointed punch, stake the engine block area around the oil filter bypass valve. Stake in 3 locations 120 degrees apart.
2. Install the oil filter. Refer to «Engine Oil and Oil Filter Replacement»(ref-188990-S13327537682005091300000) .
3. Lower the vehicle.

Scheme 345

Scheme 346

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Scheme 349

Scheme 350

Scheme 351

Scheme 352

Scheme 353

Scheme 354

Scheme 355

Scheme 356

Scheme 357

Scheme 358

Scheme 359

1. Raise and suitably support the vehicle. Refer to «JACKING AND LIFTING»(ref-188958) .
2. If equipped, remove the oil pan skid plate bolts and plate.
3. Remove the drain plug and drain the oil into a suitable container.
4. Remove the oil filter.
5. If equipped with 2WD, remove the crossmember bolts and bar.
6. If equipped with 4WD, remove the crossmember bolts and bar.
7. If equipped with 4WD, remove the front differential carrier. Refer to «DIFFERENTIAL CARRIER ASSEMBLY REPLACEMENT»(ref-188975-S23798653182005091300000) .
8. Remove the battery cable bracket bolts.
9. Remove the starter. Refer to «STARTER MOTOR»(ref-168656-S31439200122004111300000) .
10. Remove the transmission cover.
11. Remove the positive battery cable clip bolt (2).
12. Disconnect the oil level sensor electrical connector (7).
13. Remove the manual transmission bolts, if equipped.
14. Remove the automatic transmission bolts, if equipped. IMPORTANT: The oil level sensor is not reusable.
15. Remove and discard the oil level sensor.
16. Remove the oil pan bolts and nuts.
17. Remove the oil pan.
18. Remove and discard the oil pan gasket.
19. Clean and inspect the oil pan, if necessary. Refer to «Oil Pan Cleaning and Inspection»(ref-188990-S37246619822005091300000) .

Note. Any time the transmission and the engine oil pan are off of the engine at the same time, install the transmission before the oil pan. This is to allow for the proper oil pan alignment. Failure to achieve the correct oil pan alignment can result in transmission failure.

Scheme 360

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Scheme 365

Scheme 366

Scheme 367

Scheme 368

Scheme 369

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Scheme 371

Scheme 372

Scheme 373

Scheme 374

Scheme 375

Scheme 376

Scheme 377

1. Apply a 5 mm (0.197 in) wide and 25 mm (1.0 in) long bead of adhesive GM P/N 12346141, (Canadian P/N 10953433), or equivalent to both the right and left sides of the front cover to engine block junction at the oil pan sealing surfaces.
2. Apply a 5 mm (0.197 in) wide and 25 mm (1.0 in) long bead of adhesive GM P/N 12346141, (Canadian P/N 10953433), or equivalent to both the right and left sides of the rear oil seal housing to engine block junction at the oil pan sealing surfaces. IMPORTANT: Always install a NEW oil pan gasket. The oil pan gasket and oil pan must be installed and the fasteners tightened while the adhesive is still wet to the touch.
3. Install a NEW oil pan gasket into the groove in the oil pan. IMPORTANT: The oil pan alignment must always be flush or forward no more than 0.3 mm (0.011 in) from the rear face of the engine block.
4. Install the oil pan. Press the oil pan gasket into the grooves of the engine front cover and crankshaft rear oil seal housing.
5. Slide the oil pan back against a suitable straight edge.
6. Install the oil pan bolts and nuts until snug.
7. Measure the oil pan-to-transmission housing clearance using a feeler gage and a straight edge. Use the feeler gage to check the clearance at the oil pan-to-transmission housing measurement points (1). If the clearance exceeds 0.3 mm (0.011 in) at any of the oil pan-to-transmission housing measurement points (1), then repeat the step until the oil pan-to-transmission housing clearance is within specifications. The oil pan must always be forward of the rear face of the engine block. NOTE: Refer to «FASTENER NOTICE»(ref-175132-S17785009232005041500000) .
8. Tighten the oil pan bolts and nuts in the sequence shown. Tighten Tighten the bolts to 25 N.m (18 lb ft).
9. Measure the clearance at the oil pan-to-transmission housing measurement points in order to ensure proper alignment.
10. Install a NEW drain plug O-ring seal onto the drain plug.
11. Install the drain plug. Tighten Tighten the plug to 25 N.m (18 lb ft). IMPORTANT: The oil level sensor is not reusable. Use a NEW oil sensor.
12. Install a NEW oil level sensor. Tighten Tighten the sensor to 13 N.m (115 lb in).
13. Install the transmission cover. Tighten Tighten the bolts to 12 N.m (106 lb in).
14. Install the automatic transmission bolts, if equipped.
15. Install the manual transmission bolts, if equipped. Tighten Tighten the bolts to 50 N.m (37 lb ft).
16. Install the positive battery cable clip bolt (2). Tighten Tighten the bolt to 9 N.m (80 lb in).
17. Install the starter. Refer to «STARTER MOTOR»(ref-168656-S31439200122004111300000) .
18. Connect the oil level sensor electrical connector (7).
19. Install the battery cable bracket bolts. Tighten Tighten the bolts to 12 N.m (106 lb in).
20. If equipped with 2WD, Install the crossmember and bolts. Tighten Tighten the bolts to 100 N.m (74 lb ft).
21. Install the front differential carrier, if equipped with 4WD. Refer to «DIFFERENTIAL CARRIER ASSEMBLY REPLACEMENT»(ref-188975-S23798653182005091300000) .
22. If equipped with 4WD, install the crossmember and bolts. Tighten Tighten the bolts to 100 N.m (74 lb ft).
23. If equipped, install the oil pan skid plate and bolts. Tighten Tighten the bolts to 20 N.m (15 lb ft).
24. Lubricate the oil filter gasket with clean engine oil.
25. Install the oil filter. Tighten Tighten the filter to 30 N.m (22 lb ft).
26. Lower the vehicle.
27. Fill the engine with the proper capacity and quality of engine oil.

Scheme 378

Scheme 379

Scheme 380

1. Disconnect the fuel pump/oil pressure sensor electrical connector (3).
2. Using J 41712 , remove the fuel pump/oil pressure sensor. IMPORTANT: Note the alignment of the engine oil pressure sensor fitting prior to removal.
3. Remove the fuel pump/oil pressure sensor fitting, if necessary.

Scheme 381

Scheme 382

Scheme 383

Scheme 384

1. If installing the old fitting, apply sealant GM P/N 12346004, (Canadian P/N 10953480), or equivalent to the threads of the fitting.
2. Install the fitting until snug, if necessary. NOTE: Refer to «FASTENER NOTICE»(ref-175132-S17785009232005041500000) .
3. Tighten the fuel pump/oil pressure sensor fitting. Tighten 3.1. Tighten the fitting to 15 N.m (11 lb ft). 3.2. Increase torque until the centerline of the fitting (1) is 50 degrees from the centerline of the crankshaft (2).
4. If installing the old sensor, apply sealant GM P/N 12346004, (Canadian P/N 10953480), or equivalent to the threads of the sensor.
5. Using J 41712 , install the sensor. Tighten Tighten the sensor to 30 N.m (22 lb ft).
6. Connect the fuel pump/oil pressure sensor electrical connector (3).
7. Check and adjust the engine oil level, if necessary.

Scheme 385

Scheme 386

Scheme 387

1. Raise and suitably support the vehicle. Refer to «JACKING AND LIFTING»(ref-188958) .
2. Remove the drain plug and drain the oil into a suitable container.
3. Disconnect the oil level sensor electrical connector (7).
4. Remove the oil level sensor.

Note. Refer to FASTENER NOTICE .

Scheme 388

Scheme 389

Scheme 390

1. Install the drain plug. Tighten Tighten the plug to 25 N.m (18 lb ft).
2. Install the oil level sensor. Tighten Tighten the sensor to 20 N.m (15 lb ft).
3. Connect the oil level sensor electrical connector (7).
4. Lower the vehicle.
5. Fill the engine with the proper quantity and grade of oil.

Scheme 391

Scheme 392

1. Remove the oil level indicator.
2. Remove the right exhaust manifold. Refer to «EXHAUST MANIFOLD REPLACEMENT - RIGHT (4.3L ENGINE)»(ref-203989-S19178439462005110700000) .
3. Remove the oil level indicator tube bolt.
4. Remove the oil level indicator tube using a twisting motion.
5. Clean the old sealer from the indicator tube and engine block.

Scheme 393

Scheme 394

1. Apply sealant GM P/N 12346004, (Canadian P/N 10953480), or equivalent around the indicator tube 13 mm (0.5 in) below the tube bead.
2. Install the indicator tube. Rotate the oil level indicator tube into position. NOTE: Refer to «FASTENER NOTICE»(ref-175132-S17785009232005041500000) .
3. Install the indicator tube bolt. Tighten Tighten the bolt to 12 N.m (106 lb in).
4. Install the right exhaust manifold. Refer to «EXHAUST MANIFOLD REPLACEMENT - RIGHT (4.3L ENGINE)»(ref-203989-S19178439462005110700000) .
5. Install the oil level indicator.

Scheme 395

Scheme 396

1. Remove the oil pan. Refer to «Oil Pan Replacement»(ref-188990-S12863742982005091300000) .
2. Remove the oil pump bolt.
3. Remove the oil pump.
4. Inspect the oil pump locator pins for damage, and replace if required.
5. Clean and inspect the oil pump, if necessary. Refer to «Oil Pump Cleaning and Inspection»(ref-188990-S17049016652005091300000) .

Scheme 397

Scheme 398

1. Inspect for properly installed oil pump locator pins. IMPORTANT: Do not reuse the oil pump driveshaft retainer. During assembly, install a NEW oil pump driveshaft retainer.
2. Install the oil pump. Position the oil pump onto the locator pins. NOTE: Refer to «FASTENER NOTICE»(ref-175132-S17785009232005041500000) .
3. Install the oil pump bolt. Tighten Tighten the bolt to 90 N.m (66 lb ft).
4. Install the oil pan. Refer to «Oil Pan Replacement»(ref-188990-S12863742982005091300000) .

Scheme 399

Scheme 400

1. Remove the oil pan. Refer to «Oil Pan Replacement»(ref-188990-S12863742982005091300000) .
2. Remove the engine flywheel. Refer to «Engine Flywheel Replacement»(ref-188990-S34336475872005091300000) .
3. Remove the housing bolts and nut.
4. Remove the housing.
5. Remove and discard the housing gasket.
6. Clean all the sealing surfaces.
7. Inspect and replace the housing for warping, cracks, wear, or damage.

Scheme 401

Scheme 402

1. Install a NEW housing gasket.
2. Install the NEW housing with the seal using the following procedure. IMPORTANT: Do not oil or grease the seal lip or the crankshaft seal area. 2.1. Leave the sleeve in the seal and use the sleeve as a guide to ease installing the seal lip over the end of the crankshaft. 2.2. Push the housing fully onto the crankshaft until the housing is against the seal gasket and the engine. 2.3. Remove the sleeve. NOTE: Refer to «FASTENER NOTICE»(ref-175132-S17785009232005041500000) .
3. Install the crankshaft rear oil seal housing bolts and nut. Tighten Tighten the bolts and nut to 12 N.m (106 lb in).
4. Install the engine flywheel. Refer to «Engine Flywheel Replacement»(ref-188990-S34336475872005091300000) .
5. Install the oil pan. Refer to «Oil Pan Replacement»(ref-188990-S12863742982005091300000) .

Scheme 403

Scheme 404

1. Remove the automatic transmission, if equipped. Refer to «TRANSMISSION REPLACEMENT»(ref-188998-S09612205572005091400000) .
2. Remove the clutch, if equipped. Refer to «CLUTCH ASSEMBLY REPLACEMENT»(ref-189000-S16996627082005091300000) .
3. Remove the flywheel bolts.
4. Remove the flywheel (1 or 2).
5. If equipped with a manual transmission, note the position of any flywheel weights for assembly.
6. Clean and inspect the flywheel, if necessary. Refer to «Engine Flywheel Cleaning and Inspection»(ref-188990-S42705724292005091300000) .

Scheme 405

Scheme 406

Scheme 407

1. Note the position of the old flywheel weights and install the NEW flywheel weights as required. A properly installed flywheel weight will be flush or slightly below flush with the face of the flywheel.
2. Install the flywheel (1 or 2). Align the flywheel locator hole to the flywheel locator pin. NOTE: Refer to «FASTENER NOTICE»(ref-175132-S17785009232005041500000) .
3. Install the flywheel bolts. Tighten Tighten the bolts in the sequence shown to 100 N.m (74 lb ft).
4. Install the clutch, if equipped. Refer to «CLUTCH ASSEMBLY REPLACEMENT»(ref-189000-S16996627082005091300000) .
5. Install the automatic transmission, if equipped. Refer to «TRANSMISSION REPLACEMENT»(ref-188998-S09612205572005091400000) .

Exhaust Manifold Removal - Left

Note. Twist the spark plug boot one-half turn in order to release the boot. Pull on the spark plug boot only. Do not pull on the spark plug wire or the wire could be damaged.

Scheme 408

Scheme 409

1. Remove the spark plug wires from the spark plugs. 1.1. Rotate the spark plug wire boot one half turn. 1.2. Pull outward on the spark plug wire boot to release from the spark plug.
2. Remove the spark plug wires from the spark plug wire retainers.
3. Remove the exhaust manifold bolts and the stud.
4. Remove the spark plug wire shields, if applicable, and the exhaust manifold.
5. Remove and discard the exhaust manifold gaskets.

Exhaust Manifold Removal - Right

Note. Twist the spark plug boot one-half turn in order to release the boot. Pull on the spark plug boot only. Do not pull on the spark plug wire or the wire could be damaged.

Scheme 410

Scheme 411

1. Remove the spark plug wires from the spark plugs. 1.1. Rotate the spark plug wire boot one half turn. 1.2. Pull outward on the spark plug wire boot to release from the spark plug.
2. Remove the spark plug wires from the spark plug wire retainers.
3. Remove the exhaust manifold bolts.
4. Remove the spark plug wire shields and the exhaust manifold.
5. Remove and discard the exhaust manifold gaskets.

Scheme 412

Scheme 413

1. Remove the oil level indicator from the oil level indicator tube, if required.
2. Remove the oil level indicator tube bolt.
3. Remove the oil level indicator tube from the engine block.

Valve Rocker Arm and Push Rod Removal

Scheme 414

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Scheme 416

1. Remove the valve rocker arms.
2. Remove the valve rocker arm supports.
3. Remove the valve pushrods.

Scheme 417

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Scheme 423

Scheme 424

1. Remove the engine coolant temperature sensor, if applicable.
2. Remove the engine coolant temperature gage sensor, if applicable.
3. Remove the spark plugs.
4. Remove the bolts and the spark plug wire support.
5. Remove the cylinder head bolts. NOTE: After removal, place the cylinder head on two wood blocks to prevent damage.
6. Remove the cylinder head.
7. Remove and discard the cylinder head gasket.
8. Remove the cylinder head locator dowel pins, if required.

Scheme 425

Scheme 426

Scheme 427

Scheme 428

Scheme 429

Scheme 430

1. Remove the spark plugs.
2. Remove the rear bolt and the spark plug wire support.
3. Remove the cylinder head bolts. NOTE: After removal, place the cylinder head on two wood blocks to prevent damage.
4. Remove the cylinder head.
5. Remove and discard the cylinder head gasket.
6. Remove the cylinder head locator dowel pins, if required.

Engine Front Cover Installation

Scheme 431

Scheme 432

Scheme 433

1. Install the NEW engine front cover. NOTE: Refer to «FASTENER NOTICE»(ref-175132-S17785009232005041500000) .
2. Install the engine front cover bolts. Tighten Tighten the bolts to 12 N.m (106 lb in). IMPORTANT: DO NOT reuse the original crankshaft position sensor seal, O-ring. When installing the crankshaft position sensor be sure the crankshaft position sensor is fully seated and held stationary in the engine front cover crankshaft position sensor bore. A crankshaft position sensor that is not completely seated will cock in the engine front cover and may result in erratic engine operation.
3. Lubricate the NEW crankshaft position sensor seal, O-ring, with clean engine oil.
4. Install the NEW crankshaft position sensor seal, O-ring, onto the crankshaft position sensor.
5. Install crankshaft position sensor until fully seated into the engine front cover.
6. Install crankshaft position sensor bolt. Tighten Tighten the crankshaft position sensor bolt to 8 N.m (71 lb in).

Scheme 434

Scheme 435

Scheme 436

1. Inspect for properly installed oil pump locator pins. IMPORTANT: Do not reuse the oil pump driveshaft retainer. During assembly, install a NEW oil pump driveshaft retainer.
2. Install the oil pump.
3. Position the oil pump onto the pins. NOTE: Refer to «FASTENER NOTICE»(ref-175132-S17785009232005041500000) .
4. Install the oil pump bolt attaching the oil pump to the rear crankshaft bearing cap. Tighten Tighten the oil pump bolt to 90 N.m (66 lb ft).

Scheme 437

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Scheme 444

1. Apply a 5 mm (0.197 in) wide and 25 mm (1.0 in) long bead of adhesive GM P/N 12346141 (Canadian P/N 10953433) or equivalent, to both the right and left sides of the engine front cover to engine block junction at the oil pan sealing surfaces.
2. Apply a 5 mm (0.197 in) wide and 25 mm (1.0 in) long bead of adhesive GM P/N 12346141 (Canadian P/N 10953433) or equivalent, to both the right and left sides of the crankshaft rear oil seal housing to engine block junction at the oil pan sealing surfaces. IMPORTANT: Always install a NEW oil pan gasket. The oil pan gasket and oil pan must be installed and the fasteners tightened while the adhesive is still wet to the touch.
3. Install the NEW oil pan gasket into the groove in the oil pan. IMPORTANT: The oil pan alignment must always be flush or forward no more than 0.3 mm (0.011 in) from the rear face of the engine block.
4. Install the oil pan onto the engine block. Press the oil pan gasket into the grooves of the engine front cover and crankshaft rear oil seal housing.
5. Slide the oil pan back against a suitable straight edge.
6. Install the oil pan bolts and nuts, but do not tighten.
7. Measure the pan-to-transmission housing clearance using a feeler gage and a straight edge. Use a feeler gage to check the clearance between the oil pan-to-transmission housing measurement points. If the clearance exceeds 0.3 mm (0.011 in) at any of the 3 oil pan-to-transmission housing measurement points (1), then repeat the step until the oil pan-to-transmission housing clearance is within the specification. The oil pan must always be forward of the rear face of the engine block. NOTE: The alignment of the mating components is crucial. An offset greater than 0.30 mm (0.011 in) between the rear faces of the oil pan and block is not acceptable. Offsets greater than 0.30 mm (0.011 in) will affect the alignment between the engine assembly and the transmission. Mis-alignment of the engine assembly to the transmission can lead to internal and external damage to the engine assembly and/or transmission. NOTE: Refer to «FASTENER NOTICE»(ref-175132-S17785009232005041500000) .
8. Tighten the oil pan bolts and nuts in sequence (1-12). Tighten Tighten the oil pan bolts to 25 N.m (18 lb ft).
9. Measure the clearance between the 3 oil pan-to-transmission housing measurement points in order to ensure proper alignment.
10. Install a NEW oil pan drain plug seal, O-ring, onto the oil pan drain plug.
11. Install the oil pan drain plug into the oil pan. Tighten Tighten the oil pan drain plug to 25 N.m (18 lb ft).
12. Install the NEW engine oil level sensor, if applicable. Tighten Tighten the engine oil level sensor to 13 N.m (115 lb in).

Installation

Scheme 445

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Scheme 449

1. Install the valve pushrods. IMPORTANT: Be sure that the arrow on the valve rocker arm support is in the up position.
2. Install the valve rocker arm supports.
3. Apply prelube GM P/N 12345501 (Canadian P/N 992704) or equivalent, to the following valve rocker arm contact surfaces: Valve pushrod socket (1) Roller pivot (2) Valve stem tip (3)
4. Install the valve rocker arm assemblies as follows: 4.1. Finger start the bolt at location (1) 4.2. Finger start the bolt at location (2) 4.3. Finger start the bolt at location (3) 4.4. Finger start the remaining valve rocker arm bolts
5. Rotate the crankshaft balancer to position the crankshaft balancer alignment mark (1) 57-63 degrees clockwise or counterclockwise from the engine front cover alignment tab (2). NOTE: Refer to «FASTENER NOTICE»(ref-175132-S17785009232005041500000) . IMPORTANT: Once the valve rocker arm assemblies are installed and properly torqued, no additional valve lash adjustment is required.
6. Tighten the valve rocker arm bolts. Tighten Tighten valve rocker arm bolts to 30 N.m (22 lb ft).

Intake Manifold Installation

Note. Apply the proper amount of the sealant when assembling this component. Excessive use of the sealant can prohibit the component from sealing properly. A component that is not sealed properly can leak leading to extensive engine damage.

Scheme 450

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Scheme 455

1. Apply a 4.0 mm (0.157 in) patch of adhesive GM P/N 12346141 (Canadian P/N 10953433) or equivalent, to the cylinder head side of the lower intake manifold gasket at each end. IMPORTANT: The lower intake manifold gasket must be installed while the adhesive is still wet to the touch.
2. Install the lower intake manifold gasket onto the cylinder head. Use the gasket locator pins in order to properly seat the lower intake manifold gasket on the cylinder head. IMPORTANT: The lower intake manifold must be installed and the fasteners tightened while the adhesive is still wet to the touch.
3. Apply a 5 mm (0.197 in) bead of adhesive GM P/N 12346141 (Canadian P/N 10953433) or equivalent, to the front top of the engine block.
4. Extend the adhesive bead 13 mm (0.50 in) onto each lower intake manifold gasket.
5. Apply a 5 mm (0.197 in) bead of adhesive GM P/N 12346141 (Canadian P/N 10953433) or equivalent, to the rear top of the engine block.
6. Extend the adhesive bead 13 mm (0.50 in) onto each lower intake manifold gasket.
7. Install the lower intake manifold onto the engine block.
8. If reusing the fasteners, apply threadlock GM P/N 12345382 (Canadian P/N 10953489) or equivalent, to the threads of the lower intake manifold bolts.
9. Install the lower intake manifold bolts. NOTE: Proper lower intake manifold fastener tightening sequence and torque is critical. Always follow the tightening sequence, and torque the intake manifold bolts using the 3 step method. Failing to do so may distort the crankshaft bearing bore alignment and cause damage to the crankshaft bearings. NOTE: Refer to «FASTENER NOTICE»(ref-175132-S17785009232005041500000) .
10. Tighten the lower intake manifold bolts. Tighten 10.1. Tighten the bolts on the first pass in sequence (1-8) to 3 N.m (27 lb in). 10.2. Tighten the bolts on the second pass in sequence (1-8) to 12 N.m (106 lb in). 10.3. Tighten the bolts on the final pass in sequence (1-8) to 15 N.m (11 lb ft).
11. Connect the evaporative emission (EVAP) canister solenoid valve harness. 11.1. Push the elbow inward until the quick connect snaps into place. 11.2. Pull the elbow outward in order to ensure proper connection.

Distributor Installation

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1. Rotate the crankshaft balancer clockwise until the alignment marks on the crankshaft balancer are aligned with the tabs on the engine front cover and the number 1 piston is at top dead center of the compression stroke.
2. Remove the distributor cap bolts and discard.
3. Remove the distributor cap.
4. Install a NEW distributor gasket onto the distributor.
5. Align the indent hole on the driven gear with the paint mark on the distributor housing.
6. Ensure that the distributor rotor segment points to the cap hold area.
7. Align the slotted tang in the oil pump driveshaft with the distributor driveshaft. Rotate the oil pump driveshaft with a screwdriver if necessary.
8. Align the flat (1) in the distributor housing toward the front of the engine.
9. Install the distributor and distributor clamp. The flat in the distributor housing must point toward the front of the engine.
10. Once the distributor is fully seated, align the distributor rotor segment with the number 6 pointer (1) that is cast into the distributor base. If the distributor rotor segment does not come within a few degrees of the number 6 pointer (1), the gear mesh between the distributor and camshaft may be off a tooth or more. Repeat the procedure again in order to achieve proper alignment. NOTE: Refer to «FASTENER NOTICE»(ref-175132-S17785009232005041500000) .
11. Install the distributor clamp bolt. Tighten Tighten the distributor clamp bolt to 25 N.m (18 lb ft).
12. Install the distributor cap and NEW distributor cap bolts. Tighten Tighten the distributor cap bolts to 2.4 N.m (21 lb in).
13. Install the ignition coil wire harness.

Valve Rocker Arm Cover Installation - Left

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Scheme 468

1. Install the NEW valve rocker arm cover gasket into the groove of the valve rocker arm cover.
2. Install the NEW valve rocker arm cover bolt grommets into the valve rocker arm cover.
3. Install the valve rocker arm cover onto the cylinder head. NOTE: Refer to «FASTENER NOTICE»(ref-175132-S17785009232005041500000) .
4. Install the valve rocker arm cover bolts. Tighten Tighten the valve rocker arm cover bolts to 12 N.m (106 lb in).

Valve Rocker Arm Cover Installation - Right

Scheme 469

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Scheme 471

1. Install the NEW valve rocker arm cover gasket into the groove of the valve rocker arm cover.
2. Install the NEW valve rocker arm cover bolt grommets into the valve rocker arm cover.
3. Install the valve rocker arm cover onto the cylinder head. NOTE: Refer to «FASTENER NOTICE»(ref-175132-S17785009232005041500000) .
4. Install the valve rocker arm cover bolts. Tighten Tighten the valve rocker arm cover bolts to 12 N.m (106 lb in).

Scheme 472

Scheme 473

1. Apply sealant GM P/N 12346004 (Canadian P/N 10953480) or equivalent, around the oil level indicator tube 13 mm (0.5 in) below the tube bead.
2. Install the oil level indicator tube into the engine block. Rotate the oil level indicator tube into position. NOTE: Refer to «FASTENER NOTICE»(ref-175132-S17785009232005041500000) .
3. Install the oil level indicator tube bolt. Tighten Tighten the oil level indicator tube bolt to 12 N.m (106 lb in).
4. Install the oil level indicator into the oil level indicator tube, if required.

Clutch Pilot Bearing Installation

Scheme 474

1. Install the NEW clutch pilot bearing using a suitable clutch pilot bearing installation tool.
2. Measure to ensure the proper installation depth is obtained.

Engine Flywheel Installation

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Scheme 477

1. Note the position of the flywheel weights and install the NEW flywheel weights as required. A properly installed flywheel weight will be flush or slightly below flush with the face of the engine flywheel.
2. Install the engine flywheel (1 or 2) to the crankshaft. Align the engine flywheel locator hole to the flywheel locator pin. NOTE: Refer to «FASTENER NOTICE»(ref-175132-S17785009232005041500000) .
3. Install the engine flywheel bolts. Tighten Tighten the engine flywheel bolts in sequence to 100 N.m (74 lb ft).

Scheme 478

A crankcase ventilation system is used in order to provide a more complete scavenging of crankcase vapors. The air cleaner supplies fresh air through a filter to the crankcase. The crankcase mixes the fresh air with blow-by gases. This mixture then passes through a crankcase ventilation valve into the intake manifold.

The primary control is through the crankcase ventilation valve (1), which meters the flow at a rate depending on the manifold vacuum.

In order to maintain an idle quality, the crankcase ventilation valve restricts the flow when the intake manifold vacuum is high. If abnormal operating conditions arise, the system is designed in order to allow the excessive amounts of blow-by gases to back flow through the crankcase vent tube into the air cleaner in order to be consumed by normal combustion.