GM Corvette 1984-1996 Repair Guide

Cylinder Head

Print

REMOVAL & INSTALLATION



When servicing the engine, be absolutely sure to mark or tag vacuum hoses and wiring so that these items may be properly reconnected during installation. Also, when disconnecting fittings of metal lines (fuel, power brake vacuum), always use two flare nut (or line) wrenches. Hold the wrench on the large fitting with pressure on the wrench as if you were tightening the fitting (clockwise), THEN loosen and disconnect the smaller fitting from the larger fitting. If this is not done, damage to the line will result.

5.7L (VIN 8) Engine

See Figure 1

Right side
  1. Disconnect the negative battery cable. Drain the engine cooling system into a suitable container.
  2.  
  3. Remove the intake manifold, as outlined earlier in this section.
  4.  
  5. Disconnect the rear A/C brace from the exhaust manifold.
  6.  
  7. Unfasten the dipstick tube from the manifold, then remove the dipstick.
  8.  
  9. Remove the check valve from the manifold.
  10.  
  11. Disconnect the AIR hose from the converter AIR pipe.
  12.  
  13. Detach the wire from the temperature sending unit.
  14.  
  15. Tag and disconnect the spark plug wires from the plugs, head and rocker arm cover, then remove the plugs.
  16.  
  17. Raise and safely support the vehicle.
  18.  
  19. Unfasten the converter AIR pipe clamp from the manifold.
  20.  
  21. Disconnect the exhaust pipe at both manifolds.
  22.  
  23. Remove the front converter hanger bolts.
  24.  
  25. Remove the converter AIR pipe.
  26.  
  27. Carefully lower the vehicle.
  28.  
  29. Unfasten the exhaust manifold bolts, then remove the manifold with the EGR pipe.
  30.  
  31. Remove the spark plug wire retainers.
  32.  
  33. Remove the rocker arm (valve) cover.
  34.  
  35. Remove the serpentine drive belt from the A/C compressor.
  36.  
  37. Detach the electrical wires from the A/C compressor.
  38.  
  39. Loosen the 2 rear A/C compressor mounting bolts.
  40.  
  41. Remove the A/C compressor bracket nuts from the water pump
  42.  
  43. Loosen the front A/C mount bolt, then slide the compressor and bracket forward.
  44.  

When removing the pushrods, and all other valve train components, you must keep them in the same order as they were removed. These components MUST be reinstalled in the proper positions.

  1. Loosen the rocker arm nuts, then remove the pushrods.
  2.  
  3. Unfasten the head bolts, then remove the cylinder head from the vehicle. Remove and discard the gasket.
  4.  

The cylinder head should be properly cleaned and inspected before installation. Clean the gasket mating surfaces of all components. Be careful not to nick or scratch any surfaces as this will allow leak paths. Clean the bolt threads in the cylinder block and on the head bolts. Dirt will affect bolt torque. Refer to Engine Reconditioning for further details.

To install:
  1. Position a new cylinder head gasket on the block. Place the cylinder head over the locator pins and head gasket.
  2.  
  3. Install the bolts finger-tight.
  4.  
  5. Tighten the long cylinder head bolts, in the sequence shown in the accompanying figure, to 60-75 ft. lbs. (81-101 Nm). Tighten the short cylinder head bolts, in the sequence shown in the accompanying figure to 55-65 ft. lbs. (74-88 Nm).
  6.  



Click image to see an enlarged view

Fig. Fig. 1: Cylinder head mounting and bolt tightening sequence-5.7L (VIN 8) engine

  1. Install the pushrods and rocker arms. Install the rocker arm (valve) cover. Tighten the retaining bolts to the proper specifications.
  2.  
  3. The remainder of installation is the reverse of the removal procedure.
  4.  
  5. Fill the radiator with the proper type and amount of coolant. Connect the negative battery cable.
  6.  
  7. Start the engine, and allow to run (with the radiator cap still removed), until the upper hose is hot (thermostat is open). With the engine idling, add coolant to the radiator until it reaches the bottom of the filler neck.
  8.  
  9. Install the filler cap. Inspect for leaks. Turn the engine OFF .
  10.  

left side

See Figures 2 through 13

  1. Disconnect the negative battery cable.
  2.  
  3. Drain the engine cooling system into a suitable container,
  4.  
  5. Remove the intake manifold, as outlined earlier in this section.
  6.  
  7. Disconnect the AIR hose from the check valve.
  8.  
  9. Remove the alternator brace.
  10.  
  11. Detach the wire from the fan temperature sensor.
  12.  
  13. Raise and safely support the vehicle.
  14.  
  15. Disconnect the exhaust pipe from the manifold.
  16.  
  17. Carefully lower the vehicle.
  18.  
  19. Remove the exhaust manifold bolts, then remove the manifold.
  20.  
  21. Either remove the serpentine drive belt, or you can just loosen it and remove it from the AIR pump pulley.
  22.  
  23. Remove the mounting bolts, then remove the AIR pump with the bracket.
  24.  



Click image to see an enlarged view

Fig. Fig. 2: View of the AIR pump and bracket mounting bolts



Click image to see an enlarged view

Fig. Fig. 3: Unfasten the retainers, then remove the AIR pump and bracket, as an assembly, from the engine

  1. Remove the rocker arm (valve) cover.
  2.  



Click image to see an enlarged view

Fig. Fig. 4: Remove the rocker arm (valve) cover

  1. Tag and disconnect the spark plug wires, then remove the plugs.
  2.  
  3. Unfasten the power steering and alternator mounting bracket from the cylinder head.
  4.  



Click image to see an enlarged view

Fig. Fig. 5: Remove the power steering and alternator mounting bracket from the cylinder head

When removing the pushrods, and all other valve train components, you must keep them in the same order as they were removed. These components MUST be reinstalled in the proper positions.

  1. Loosen or remove the rocker arm nuts, as applicable, then remove the pushrods. Make sure to keep all components in the proper order for installation.
  2.  



Click image to see an enlarged view

Fig. Fig. 6: Loosen the rocker arm nuts (see arrows)



Click image to see an enlarged view

Fig. Fig. 7: Remove the rocker arm retaining nut (1) and rocker arm (2)



Click image to see an enlarged view

Fig. Fig. 8: Then, pull the pushrods from the cylinder head

  1. Unfasten the head bolts, then remove the cylinder head from the vehicle. Remove and discard the gasket.
  2.  



Click image to see an enlarged view

Fig. Fig. 9: Loosen the cylinder head bolts gradually, starting from the inside and working out



Click image to see an enlarged view

Fig. Fig. 10: When you remove the cylinder head bolts, keep them in order, because 2 different lengths of bolts are used



Click image to see an enlarged view

Fig. Fig. 11: Carefully lift the cylinder head off of the engine block and place on a suitable workbench

The cylinder head should be properly cleaned and inspected before installation. Clean the gasket mating surfaces of all components. Be careful not to nick or scratch any surfaces as this will allow leak paths. Clean the bolt threads in the cylinder block and on the head bolts. Dirt will affect bolt torque. Refer to Engine Reconditioning for further details.



Click image to see an enlarged view

Fig. Fig. 12: Remove and discard the cylinder head gasket, then thoroughly clean the gasket mating surfaces

To install:
  1. Position a new cylinder head gasket on the block. Place the cylinder head over the locator pins and head gasket.
  2.  
  3. Install the bolts finger-tight.
  4.  
  5. Tighten the long cylinder head bolts, in the sequence shown in the accompanying figure, to 60-75 ft. lbs. (81-101 Nm). Tighten the short cylinder head bolts, in the sequence shown in the accompanying figure to 55-65 ft. lbs. (74-88 Nm).
  6.  



Click image to see an enlarged view

Fig. Fig. 13: Always use a torque wrench to tighten the cylinder head bolts to specifications

  1. Install the pushrods and rocker arms. Install the rocker arm (valve) cover. Tighten the retaining bolts to the proper specifications.
  2.  
  3. The remainder of installation is the reverse of the removal procedure.
  4.  
  5. Fill the radiator with the proper type and amount of coolant. Connect the negative battery cable.
  6.  
  7. Start the engine, and allow to run (with the radiator cap still removed), until the upper hose is hot (thermostat is open). With the engine idling, add coolant to the radiator until it reaches the bottom of the filler neck.
  8.  
  9. Install the filler cap. Inspect for leaks. Turn the engine OFF .
  10.  

5.7L (VIN J) Engines

See Figure 14

RIGHT SIDE
  1. Disconnect the negative battery cable and properly relieve fuel system pressure.
  2.  
  3. Drain the engine coolant into a suitable container.
  4.  
  5. Remove the intake plenum assembly.
  6.  
  7. Remove the right injector housing.
  8.  
  9. Remove the right bank valve lifters.
  10.  
  11. Remove the alternator assembly.
  12.  
  13. Disconnect the right exhaust manifold from the cylinder head. It is not necessary to completely remove the exhaust manifold from the vehicle for cylinder head removal.
  14.  
  15. If raised, lower the vehicle for underhand access.
  16.  
  17. Remove the vacuum hose from secondary port throttle valve actuator.
  18.  
  19. Remove the access plug from the right cylinder head.
  20.  
  21. Remove the top bolt attaching the right secondary timing chain fixed guide.
  22.  
  23. Remove cylinder head bolts, then remove the cylinder head and gasket from the vehicle. Discard the gasket.
  24.  

To install:
  1. Thoroughly clean the cylinder head and cylinder case mating surfaces. Make sure both surfaces are free of any foreign matter, nicks or scratches. The threads in both the bolts holes and on the bolts must be clean and free of old sealer.
  2.  

Cylinder head gaskets are not interchangeable between cylinder banks.

  1. Install the cylinder head locating dowels into block, if loosened or removed, then position the new gasket in place on the cylinder case.
  2.  
  3. Install the cylinder head over the dowels. Coat bolt threads and washers with clean engine oil and insert.
  4.  
  5. Tighten the cylinder head bolts, in the sequence shown in the accompanying figure, as follows:

    1st pass-45 ft. lbs. (60 Nm)
     
    2nd pass-74 ft. lbs. (100 Nm)
     
    3rd pass-118 ft. lbs. (160 Nm)
     

  6.  
  7. Apply Loctite® 262 to the fixed guide top bolt threads, install the bolt and tighten to 19 ft. lbs. (26 Nm).
  8.  
  9. Install the access plug into the cylinder head and torque to 15 ft. lbs. (20 Nm).
  10.  
  11. Connect the vacuum hose to the actuator.
  12.  
  13. Raise and support vehicle, drain the engine oil.
  14.  
  15. Install the exhaust manifold.
  16.  
  17. If still supported, lower the vehicle for underhood access.
  18.  
  19. Install the alternator.
  20.  
  21. Install valve lifters.
  22.  
  23. Install the right injector housing assembly.
  24.  
  25. Install the plenum assembly.
  26.  
  27. Fill the engine crankcase with the proper type and amount of engine oil.
  28.  
  29. Tighten the fuel filler cap and properly refill the cooling system.
  30.  
  31. Connect the negative battery cable.
  32.  
  33. If equipped, reset the CHANGE OIL indicator, as outlined in General Information & Maintenance of this repair guide.
  34.  



Click image to see an enlarged view

Fig. Fig. 14: Cylinder head bolt tightening sequence-5.7L (VIN J) engines

LEFT SIDE
  1. Disconnect the negative battery cable and properly relieve fuel system pressure.
  2.  
  3. Drain the engine coolant into a suitable container.
  4.  
  5. Remove the intake plenum assembly.
  6.  
  7. Remove the left injector housing.
  8.  
  9. Remove the vacuum hose from the secondary port throttle valve actuator.
  10.  
  11. Remove the power brake booster assembly.
  12.  
  13. Remove the left bank valve lifters.
  14.  
  15. Remove the AIR control valve hoses, then disengage the electrical connector.
  16.  
  17. Remove the camshaft position sensor.
  18.  
  19. Disconnect the left exhaust manifold from the cylinder head. It is not necessary to completely remove the exhaust manifold from the vehicle for cylinder head removal.
  20.  
  21. Remove the access plug from the left cylinder head.
  22.  
  23. Remove the bolt attaching the left secondary timing chain guide.
  24.  
  25. Remove the cylinder head bolts. Remove the cylinder head and gasket from the vehicle. Discard the gasket.
  26.  

To install:
  1. Thoroughly clean the cylinder head and cylinder case mating surfaces. Make sure both surfaces are free of any foreign matter, nicks or scratches. The threads in both the bolts holes and on the bolts must be clean and free of old sealer.
  2.  

Cylinder head gaskets are not interchangeable between cylinder banks.

  1. Install the cylinder head locating dowels into block, if loosened or removed, then position the new gasket in place on the cylinder case.
  2.  
  3. Install the cylinder head over the dowels. Coat bolt threads and washers with clean engine oil and insert.
  4.  
  5. Tighten the cylinder head bolts, in the sequence shown in the accompanying figure, as follows:

    1st pass-45 ft. lbs. (60 Nm)
     
    2nd pass-74 ft. lbs. (100 Nm)
     
    3rd pass-118 ft. lbs. (160 Nm)
     

  6.  
  7. Apply Loctite® 262 to the fixed guide bolt threads, install the bolt and tighten to 19 ft. lbs. (26 Nm).
  8.  
  9. Install the access plug into the cylinder head and tighten to 15 ft. lbs. (20 Nm).
  10.  
  11. Connect the vacuum hose to the actuator.
  12.  
  13. Raise and support vehicle, drain the engine oil and lower the vehicle.
  14.  
  15. Install the exhaust manifold.
  16.  
  17. Install the camshaft position sensor.
  18.  
  19. Connect the AIR control valve hoses and electrical connector.
  20.  
  21. Install the valve lifters.
  22.  
  23. Install the left injector housing assembly.
  24.  
  25. Install the plenum assembly.
  26.  
  27. Fill the engine crankcase with the proper type and amount of engine oil.
  28.  
  29. Tighten the fuel filler cap and properly refill the cooling system.
  30.  
  31. Connect the negative battery cable.
  32.  
  33. If equipped, reset the CHANGE OIL indicator, as outlined in General Information & Maintenance of this repair guide.
  34.  

5.7L (VIN P and 5) Engines

See Figure 15

RIGHT SIDE
  1. Disconnect the negative battery cable and properly relieve the fuel system pressure.
  2.  
  3. Raise and support the vehicle safely.
  4.  
  5. Disconnect the catalytic converter.
  6.  
  7. Drain the engine cooling system, then lower the vehicle.
  8.  
  9. Remove the lower radiator and heater hoses from the water pump.
  10.  
  11. Disconnect the power steering pump reservoir from the cylinder head and reposition aside.
  12.  
  13. Remove the coil and bracket assembly.
  14.  
  15. Remove the intake manifold.
  16.  
  17. Remove the spark plug wires from the clips, then remove the front wire bracket.
  18.  
  19. Remove the oil level indicator tube.
  20.  
  21. Disconnect the spark plug wires from the plugs, then remove the spark plugs from the cylinder head.
  22.  
  23. Remove the right exhaust manifold.
  24.  
  25. Using a backup wrench on the pipe fitting, disconnect the coolant air bleed pipe from the left cylinder head.
  26.  

When removing the pushrods, and all other valve train components, you must keep them in the same order as they were removed. These components MUST be reinstalled in the proper positions.

  1. Remove the right valve rocker cover, then remove the rocker arm and pushrod assemblies.
  2.  
  3. Remove the cylinder head bolts.
  4.  
  5. Remove the cylinder head along with the coolant air bleed pipe, then remove the head gasket.
  6.  
  7. If necessary, remove the coolant air bleed pipe from the cylinder head.
  8.  

The cylinder head should be properly cleaned and inspected before installation. Clean the gasket mating surfaces of all components. Be careful not to nick or scratch any surfaces as this will allow leak paths. Clean the bolt threads in the cylinder block and on the head bolts. Dirt will affect bolt torque. Refer to Engine Reconditioning for further details.

Click image to see an enlarged view

Fig. Fig. 15: Exploded view of the cylinder head mounting and bolt tightening sequence-5.7L (VIN P and 5) engine

To install:
  1. Thoroughly clean the cylinder head and cylinder case mating surfaces. Make sure both surfaces are free of any foreign matter, nicks or scratches. The threads in both the bolts holes and on the bolts must be clean and free of old sealer.
  2.  
  3. If removed, install the coolant air bleed pipe to the cylinder head, finger-tight.
  4.  
  5. Position the new gasket in place on the cylinder case with the yellow tab facing up. Install the cylinder head over the dowel pins and gasket.
  6.  
  7. Coat the bolts with 1052080, or an equivalent sealant. Install and tighten the cylinder head bolts, using 3 passes of the proper sequence, to 65 ft. lbs. (88 Nm).
  8.  
  9. Install the rocker arm and pushrod assemblies.
  10.  
  11. Install the valve rocker cover and tighten the bolts to 75 inch lbs. (8 Nm) for 1992 vehicles or to 100 inch lbs. (11 Nm) for 1993-96 vehicles.
  12.  
  13. Connect the coolant air bleed pipe to the left cylinder head and torque the pipe to both cylinder heads. Using a backup wrench, tighten the coolant air bleed pipe to 30 ft. lbs. (41 Nm).
  14.  
  15. Install the right exhaust manifold.
  16.  
  17. Install the spark plugs and tighten to 11 ft. lbs. (15 Nm).
  18.  
  19. Connect the spark plug wires to the plugs, then install the oil level indicator tube.
  20.  
  21. Install the front wire bracket, then connect the spark plug wire harness assembly to the wire bracket.
  22.  
  23. Install the intake manifold.
  24.  
  25. Install the coil and bracket assembly.
  26.  
  27. Position and secure the power steering pump reservoir.
  28.  
  29. Install the lower radiator and heater hoses to the water pump.
  30.  
  31. Raise and support the vehicle safely.
  32.  
  33. Connect the catalytic converter, then lower the vehicle.
  34.  
  35. Properly fill the cooling system.
  36.  
  37. Tighten the fuel filler cap and connect the negative battery cable.
  38.  

LEFT SIDE
  1. Disconnect the negative battery cable and properly relieve the fuel system pressure.
  2.  
  3. Raise and support the vehicle safely.
  4.  
  5. Disconnect the catalytic converter.
  6.  
  7. Drain the engine cooling system, then lower the vehicle.
  8.  
  9. Remove the upper radiator hose.
  10.  
  11. Remove the serpentine drive belt.
  12.  
  13. Remove the intake manifold.
  14.  
  15. Remove the left wheel well lower center panel.
  16.  
  17. Disconnect the air conditioning compressor from the bracket and position aside. Use care not to kink or damage the refrigerant lines. Remove the compressor and alternator brace.
  18.  
  19. Remove the spark plug wire bracket, disconnect the wires from the spark plugs and remove the spark plugs from the cylinder head.
  20.  
  21. Remove the left exhaust manifold.
  22.  
  23. Remove the remaining alternator brace, then remove the alternator.
  24.  
  25. Disconnect the AIR diverter valve hose.
  26.  
  27. Remove the left valve rocker cover.
  28.  
  29. Remove the drive belt idler pulley, then remove the drive belt tensioner.
  30.  
  31. Disconnect the power steering lines from the pump, then remove the pump. Plug the openings to prevent system contamination or excessive fluid loss.
  32.  
  33. Remove the spark plug and coil wires from the distributor.
  34.  
  35. Remove the accessory mounting bracket.
  36.  
  37. Remove the rocker arm and pushrod assemblies.
  38.  
  39. Disconnect the coolant air bleed pipe from the cylinder head.
  40.  
  41. Remove the cylinder head bolts, then remove the cylinder head and gasket.
  42.  

To install:
  1. Thoroughly clean the cylinder head and cylinder case mating surfaces. Make sure both surfaces are free of any foreign matter, nicks or scratches. The threads in both the bolts holes and on the bolts must be clean and free of old sealer.
  2.  
  3. Position the new gasket in place on the cylinder case with the yellow tab facing up. Install the cylinder head over the dowel pins and gasket.
  4.  
  5. Coat the bolts with 1052080, or an equivalent sealant. Install and tighten the cylinder head bolts, using 3 passes of the proper sequence, to 65 ft. lbs. (88 Nm).
  6.  
  7. Connect the coolant air bleed pipe to the cylinder head and tighten to 30 ft. lbs. (41 Nm).
  8.  
  9. Install the rocker arm and pushrod assemblies.
  10.  
  11. Install the accessory mounting bracket and bolts. Tighten the bolts to 25 ft. lbs. (34 Nm) for 1992 vehicles or to 31 ft. lbs. (42 Nm) for 1993-96 vehicles.
  12.  
  13. Connect the spark plug and coil wires to the distributor.
  14.  
  15. Install the power steering pump, then remove the plugs from the openings and connect the lines.
  16.  
  17. Install the drive belt tensioner, then install the idler pulley. Tighten the tensioner and pulley bolts to 24 ft. lbs. (33 Nm).
  18.  
  19. Install the left valve rocker cover and bolts. Tighten the bolts to 75 inch lbs. (8 Nm) for 1992 vehicles or to 100 inch lbs. (11 Nm) for 1993-96 vehicles.
  20.  
  21. Connect the AIR diverter valve hose and install the alternator lower brace.
  22.  
  23. Install the left exhaust manifold.
  24.  
  25. Install the spark plugs and tighten to 11 ft. lbs. (15 Nm). Connect the spark plug wires to the plugs and insert the wires into the brackets.
  26.  
  27. Install the air conditioning compressor and alternator brace, then install the compressor.
  28.  
  29. Install the left wheel well lower center panel.
  30.  
  31. Install the intake manifold.
  32.  
  33. Install the serpentine drive belt and the upper radiator hose.
  34.  
  35. Raise and safely support the vehicle, then connect the catalytic converter and lower the vehicle.
  36.  
  37. Properly fill the engine cooling system.
  38.  
  39. Tighten the fuel filler cap and connect the negative battery cable.
  40.  
  41. Bleed the power steering system.
  42.  

 
label.common.footer.alt.autozoneLogo