GM Cadillac 1967-1989 Repair Guide

Cylinder Head Cover

Print

REMOVAL & INSTALLATION



See Figures 1 and 2

6-Cylinder Engines
  1. Remove air cleaner.
  2.  
  3. Disconnect and reposition as necessary any vacuum or PCV hoses that obstruct the valve covers.
  4.  

It may be necessary to reposition the air conditioning refrigerant hoses out of the way of the valve cover, however do not disconnect the lines from the compressor.

  1. Disengage the necessary electrical wiring (spark plug, etc.) from the valve cover clips.
  2.  
  3. Unbolt and remove the valve covers.
  4.  

Do not pry the covers off if they seem stuck. Instead, gently tap around each cover with a rubber mallet until the old gasket or sealer breaks loose.

To install:
  1. Use a new valve cover gasket or RTV (or any equivalent) sealer. If using sealer, follow directions on the tube. Install valve cover and tighten cover bolts to 36 in. lbs. (4 Nm).
  2.  
  3. Connect and reposition all vacuum and PCV hoses, and reconnect electrical and/or spark plug wires at the cover clips. Install the air cleaner.
  4.  



Click image to see an enlarged view

Fig. Fig. 1: Remove all necessary brackets - valve cover removal



Click image to see an enlarged view

Fig. Fig. 2: Removing the valve cover - always replace the gasket

V8 Gasoline Engines Except 8-250, 8-273 and 8-307

RIGHT SIDE



  1. Disconnect the negative battery cable. Remove the air cleaner.
  2.  
  3. On the 1985-86 models, disconnect the CCC harness from the intake manifold and the oxygen sensor.
  4.  
  5. At the exhaust manifold, disconnect the AIR hose.
  6.  
  7. Disconnect the wires from the alternator, the choke and the spark plugs, then the harness from the rocker cover (lay it aside).
  8.  
  9. Remove the EGR valve.
  10.  
  11. Remove the rocker arm cover bolts and the cover.
  12.  
  13. Using a putty knife, clean the gasket mounting surfaces.
  14.  
  15. To install, use a new gasket or sealant and reverse the removal procedures. Start the engine and check for leaks.
  16.  

LEFT SIDE



  1. Disconnect the negative battery cable. Remove the air cleaner.
  2.  
  3. Disconnect the power brake pipe from the carburetor and the booster.
  4.  
  5. Disconnect the AIR hose from the exhaust manifold.
  6.  
  7. At the rocker arm cover, remove the PCV valve.
  8.  
  9. Disconnect the wire from the oxygen sensor.
  10.  
  11. Remove the rocker arm cover bolts and the cover.
  12.  
  13. Using a putty knife, clean the gasket mounting surfaces.
  14.  
  15. To install, use a new gasket or sealant and reverse the removal procedures. Start the engine and check for leaks.
  16.  

8-250 Engine1982-85 LEFT

  1. Remove the air cleaner.
  2.  
  3. Remove the spark plug wires and retainers from the lower valve cover studs.
  4.  
  5. Disconnect the accelerator, transmission downshift, and cruise control cables. Remove the bracket.
  6.  
  7. Remove the PCV valve from the cover grommet.
  8.  
  9. Remove the seven attaching studs and screws and remove the cover.
  10.  

To install:
  1. Apply RTV sealant to the two short edges where the cylinder head and intake manifold meet at the front and rear of the cylinder head. Install new triangular seals in position.
  2.  
  3. Reseal the rocker arm cover with gasket part No. 1627340 or apply a continuous bead 3-4mm in diameter of RTV sealant to the sealing flange of the cover. Do not use RTV on gasket.
  4.  
  5. Position the cover to the cylinder head and install the screws. Torque to 4 ft. lbs. (5 Nm). Do not slide the cover around to align screws.
  6.  
  7. Install the PCV valve in the cover grommet.
  8.  
  9. Connect the accelerator, transmission downshift, and cruise control cables to the throttle body.
  10.  
  11. Connect the spark plug wires and retainers to the lower valve cover studs.
  12.  
  13. Install the air cleaner.
  14.  

1982-85 RIGHT
  1. Disconnect the negative battery cable.
  2.  
  3. Remove the air cleaner. Carefully loosen screws securing A/C hose to rear of compressor. DO NOT DISCHARGE THE SYSTEM. Pivot hose to allow cover removal.
  4.  
  5. Disconnect two clips holding wiring harness to EGR valve shield and EGR solenoid bracket.
  6.  
  7. Remove the spark plug wires and retainers from the lower valve cover studs.
  8.  
  9. Remove the AIR management valve.
  10.  
  11. Remove vacuum line from the throttle body to vacuum pump.
  12.  
  13. Remove the EGR valve and heat shield.
  14.  
  15. Remove the seven attaching screws and studs and remove the cover. Remove and discard triangular end seals and clean RTV from the engine surfaces.
  16.  

To install:
  1. Inspect sealing flange. Apply RTV sealer to engine surface. Install new triangular seals.
  2.  
  3. Install and fully seat rocker arm cover gasket in cover. Do not use RTV on gasket.
  4.  
  5. Carefully position cover to cylinder head and install screws. Torque evenly to 8 ft. lbs. (11 Nm).
  6.  
  7. Install AIR management valve and connect vacuum line from throttle body to vacuum pump.
  8.  
  9. Install spark wire retainers, clip wiring harness in place at EGR valve shield and solenoid bracket.
  10.  
  11. Reposition A/C hose and tighten retaining screw. Install air cleaner.
  12.  

8-273 Engine1986-89 LEFT

See Figure 3

  1. Disconnect the negative battery cable.
  2.  
  3. Remove the air cleaner.
  4.  
  5. Remove the accessory drive belt.
  6.  
  7. Loosen the two lower power steering pump bracket nuts.
  8.  
  9. Remove the power steering pump, belt tensioner and bracket assembly and position out of the way toward the front of the engine.
  10.  
  11. Disconnect the the left side spark plug wires and conduit.
  12.  
  13. Disconnect the throttle spring and CC rod.
  14.  
  15. Remove the PCV valve.
  16.  
  17. Remove the seven rocker arm cover attaching screws and remove the rocker arm cover.
  18.  
  19. Remove the cover seal and the triangular seals and discard.
  20.  

To install:
  1. Install new triangular seals and a new molded seal into the groove in the cover.
  2.  
  3. Tighten the attaching screws to 96 in. lbs. (11 Nm).
  4.  
  5. Connect the throttle spring and CC rod.
  6.  
  7. Connect the the left side spark plug wires and conduit.
  8.  
  9. Install the power steering pump, belt tensioner, bracket assembly and belt.
  10.  
  11. Install the PCV valve.
  12.  
  13. Install the accessory drive belt.
  14.  
  15. Install the air cleaner.
  16.  
  17. Connect the negative battery cable.
  18.  

1986-89 RIGHT
  1. Disconnect the negative battery cable.
  2.  
  3. Remove the air cleaner.
  4.  
  5. Remove the heater hose bracket and vacuum lines from the valve cover.
  6.  
  7. Disconnect the the right side spark plug wires and conduit.
  8.  
  9. Disconnect all electrical connections positioned over the valve cover.
  10.  
  11. Remove the seven rocker arm cover attaching screws and remove the rocker arm cover.
  12.  
  13. Remove the cover seal and the triangular seals and discard.
  14.  

To install:
  1. Install new triangular seals and a new molded seal into the groove in the cover.
  2.  
  3. Tighten the attaching screws to 96 in. lbs. (11 Nm).
  4.  
  5. Connect all electrical connections positioned over the valve cover.
  6.  
  7. Connect the the right side spark plug wires and conduit.
  8.  
  9. Connect the heater hose bracket and vacuum lines to the valve cover.
  10.  
  11. Install the air cleaner.
  12.  
  13. Connect the negative battery cable.
  14.  



Click image to see an enlarged view

Fig. Fig. 3: Apply sealer to the valve cover before assembling - common cover shown, bolt holes may vary

8-307 Engine

LEFT



  1. Disconnect the negative battery cable.
  2.  
  3. Disconnect the spark plug wires.
  4.  
  5. Disconnect the air cleaner to crankcase inlet pipe and filter.
  6.  
  7. Disconnect the following wires:
  8.  
  9. ILC anti-dieseling solenoid
  10.  
  11. RVB/ILC/EGR solenoid assembly
  12.  
  13. Oil pressure sensor
  14.  
  15. Temperature sensor
  16.  
  17. Coolant sensor
  18.  
  19. Alternator
  20.  
  21. Remove the ILC anti-dieseling solenoid.
  22.  
  23. Remove the alternator drive belt and rear bracket.
  24.  
  25. Loosen the exhaust manifold upper shroud only.
  26.  
  27. Remove the EGR valve.
  28.  
  29. Remove the oil level indicator.
  30.  
  31. Remove the valve cover screws nuts.
  32.  
  33. Install tool BT - 8315 or J-34144 midway between the ends of the valve cover, on the upper side. Tighten the screw to apply a load on the cover.
  34.  
  35. Using a rubber mallet, strike on the side of the valve cover, above where the tool is installed.
  36.  


WARNING
Use a cloth to absorb the blow of the mallet or damage to to the cover may result.

To install:
  1. Clean the valve cover and head mating surfaces.
  2.  
  3. Apply a 1 / 4 in. (6mm) bead of RTV sealant on the valve cover.
  4.  

The RTV sealer must be wet to the touch at the time of valve cover attachment to the cylinder head.

  1. Install the valve cover and tighten the attaching screws/nuts to 90 in. lbs. (10 Nm).
  2.  
  3. Install the oil level indicator.
  4.  
  5. Install the EGR valve.
  6.  
  7. Install the alternator drive belt and rear bracket.
  8.  
  9. Install the ILC anti-dieseling solenoid.
  10.  
  11. Tighten the exhaust manifold upper shroud.
  12.  
  13. Connect the following wires:
  14.  
  15. ILC anti-dieseling solenoid
  16.  
  17. RVB/ILC/EGR solenoid assembly
  18.  
  19. Oil pressure sensor
  20.  
  21. Temperature sensor
  22.  
  23. Coolant sensor
  24.  
  25. Alternator
  26.  
  27. Connect the air cleaner to crankcase inlet pipe and filter.
  28.  
  29. Connect the spark plug wires.
  30.  
  31. Connect the negative battery cable.
  32.  

RIGHT
  1. Disconnect the negative battery cable.
  2.  
  3. Disconnect the spark plug wires.
  4.  
  5. Disconnect the PCV valve and hose.
  6.  
  7. Reposition the the heater hoses and move aside.
  8.  
  9. Disconnect the ILC anti-dieseling solenoid and hoses.
  10.  
  11. Disconnect the following wires:
  12.  
  13. ILC anti-dieseling solenoid
  14.  
  15. AIR
  16.  
  17. Oxygen sensor
  18.  
  19. Disconnect the canister purge hose.
  20.  
  21. Remove the following on the AIR system:
  22.  
  23. AIR hoses to the AIR switching valve and catalytic converter pipe
  24.  
  25. AIR switching valve
  26.  
  27. AIR/air conditioning drive belt
  28.  
  29. AIR pump pulley
  30.  
  31. Disconnect the air conditioning compressor rear bracket.
  32.  
  33. Remove the valve cover screws nuts.
  34.  
  35. Install tool BT-8315 or J-34144 midway between the ends of the valve cover, on the upper side. Tighten the screw to apply a load on the cover.
  36.  
  37. Using a rubber mallet, strike on the side of the valve cover, above where the tool is installed.
  38.  

To install:
  1. Clean the valve cover and head mating surfaces.
  2.  
  3. Apply a 1 / 4 bead of RTV sealant on the valve cover.
  4.  

The RTV sealer must be wet to the touch at the time of valve cover attachment to the cylinder head.

  1. Install the valve cover and tighten the attaching screws/nuts to 90 in. lbs. (10 Nm).
  2.  
  3. Connect the air conditioning compressor rear bracket.
  4.  
  5. Install the air conditioning drive belt.
  6.  
  7. Install the canister purge hose.
  8.  
  9. Install the following on the AIR system:
  10.  
  11. AIR hoses to the AIR switching valve and catalytic converter pipe
  12.  
  13. AIR switching valve
  14.  
  15. AIR/AC drive belt
  16.  
  17. AIR pump pulley
  18.  
  19. Connect the ILC anti-dieseling solenoid and hoses.
  20.  
  21. Connect the following wires:
  22.  
  23. ILC anti-dieseling solenoid
  24.  
  25. AIR
  26.  
  27. Oxygen sensor
  28.  
  29. Install the PCV valve and hose.
  30.  
  31. Reposition the heater hoses.
  32.  
  33. Connect the canister purge hose.
  34.  
  35. Connect the spark plug wires.
  36.  
  37. Connect the negative battery cable.
  38.  

V8 Diesel Engines

See Figure 4

  1. Refer to the Injection Lines, removal and installation procedures, under the Diesel Fuel System in Fuel System , then remove the fuel injection lines.
  2.  
  3. Remove the rocker arm cover-to-cylinder head screws and any accessory mounting brackets (if necessary).
  4.  
  5. Using the Valve Cover Removal tool No. J-34144 or BT-8315, place it midway between the ends of the valve cover (on the upper side), then tighten the screw to lift the rocker arm cover.
  6.  
  7. Using a rubber mallet and a shop cloth (placed on the rocker arm cover above the removal tool to absorb the blow), strike the cover to complete remove it.
  8.  
  9. Using a putty knife, clean the gasket mounting surfaces.
  10.  
  11. Using RTV sealant, apply a 1 / 4 in. (6mm) bead to the rocker arm cover.
  12.  

When installing the rocker arm cover, the sealant must be wet to the touch.

  1. To install, reverse the removal procedures. Start the engine and check for leaks.
  2.  



Click image to see an enlarged view

Fig. Fig. 4: Removing the cylinder head cover on diesel engines

 
label.common.footer.alt.autozoneLogo