GM Astro/Safari 1985-1996 Repair Guide

Rocker Arm (Valve) Cover

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REMOVAL & INSTALLATION



2.5L Engine

See Figure 1



Click image to see an enlarged view

Fig. Fig. 1: Exploded view of the rocker arm cover mounting-2.5L engine

  1. Disconnect the negative battery cable for safety.
  2.  
  3. From inside the vehicle, remove the engine cover. For details, please refer to General Information & Maintenance of this information.
  4.  
  5. Remove the air cleaner.
  6.  
  7. Disconnect the Positive Crankcase Ventilation (PCV) valve hose, the ignition wires from the rocker arm cover.
  8.  
  9. Remove the Exhaust Gas Recirculation (EGR) valve.
  10.  
  11. From the intake stud, label and disconnect the vacuum hoses.
  12.  
  13. Remove the rocker arm cover-to-cylinder head bolts and the cover.
  14.  
  15. Using a plastic scraper, clean the gasket mounting surface.
  16.  

Be sure to use solvent to remove any oil or grease that may remain on the sealing surfaces.

To install:
  1. Apply a 3 / 16 in. (5mm) continuous bead of RTV sealant to the cylinder head, inboard of the bolts holes. While the sealant is still wet (within about 10 minutes of applications), install the rocker arm cover, then tighten the retainers to 90 inch lbs. (10 Nm).
  2.  
  3. Connect the vacuum hoses to the intake stud as labelled.
  4.  
  5. Install the Exhaust Gas Recirculation (EGR) valve.
  6.  
  7. Connect the Positive Crankcase Ventilation (PCV) valve hose, the ignition wires to the rocker arm cover.
  8.  
  9. Install the air cleaner.
  10.  
  11. Connect the negative battery cable.
  12.  
  13. Start the engine and check for leaks.
  14.  
  15. Once the engine has cooled sufficiently, install the engine cover to the passenger compartment.
  16.  

4.3L Engine

See Figures 2, 3, 4, 5, 6 and 7



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Fig. Fig. 2: Exploded view of a typical 4.3L rocker arm cover mounting



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Fig. Fig. 3: Loosen the rocker arm retaining bolts using a wrench or ratchet and suitable driver ...



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Fig. Fig. 4: ... then remove the bolts from the cylinder head and valve cover



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Fig. Fig. 5: Lift and remove the valve cover from the cylinder head ...



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Fig. Fig. 6: ... then remove and discard the old gasket



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Fig. Fig. 7: Exploded view of the late-model 4.3L Vortec engine rocker arm cover mounting-1996 shown

RIGHT SIDE (1985-92)
  1. Disconnect the negative battery cable for safety.
  2.  
  3. From inside the vehicle, remove the engine cover. For details, please refer to General Information & Maintenance of this information.
  4.  
  5. Remove the air cleaner. Disconnect the Air Injection Reaction (AIR) hoses from the diverter valve, then the diverter valve bracket from the intake manifold.
  6.  
  7. From the alternator bracket, remove the engine oil filler tube and the transmission (if equipped with an automatic transmission) oil filler tube.
  8.  
  9. From the valve cover, remove the Positive Crankcase Ventilation (PCV) valve.
  10.  
  11. From the back side of the right cylinder head, remove the AIR pipe-to-cylinder head bolts and move the pipe (hose) out of the way.
  12.  
  13. Remove the ignition wires from the valve cover and the distributor cap (with the wires attached), then move the cap out of the way.
  14.  
  15. Remove the rocker arm cover-to-cylinder head bolts and the cover.
  16.  
  17. Using a plastic scraper, clean the gasket mounting surfaces.
  18.  

To install:
  1. Using a new gasket, install the rocker cover and tighten the retainers to 90 inch lbs. (10 Nm).
  2.  
  3. Install the ignition wires to the valve cover and the distributor cap.
  4.  
  5. To the back side of the right cylinder head, install the AIR pipe-to-cylinder head bolts.
  6.  
  7. To the rocker cover, install the Positive Crankcase Ventilation (PCV) valve.
  8.  
  9. To the alternator bracket, install the engine oil filler tube and the transmission (if equipped with an automatic transmission) oil filler tube.
  10.  
  11. Install the air cleaner. Connect the Air Injection Reaction (AIR) hoses to the diverter valve.
  12.  
  13. Connect the negative battery cable.
  14.  
  15. Start the engine and check for leaks.
  16.  
  17. Once the engine has cooled sufficiently, install the engine cover to the passenger compartment.
  18.  

RIGHT SIDE (1993-95)
  1. Disconnect the negative battery cable for safety.
  2.  
  3. From inside the vehicle, remove the engine cover. For details, please refer to General Information & Maintenance of this information.
  4.  
  5. Remove the air cleaner, adapter and heat stove tube.
  6.  
  7. Disconnect the spark plug wire bracket at the side of the cylinder head, then remove the wires from the clip at the rear of the cylinder head.
  8.  
  9. Remove the Positive Crankcase Ventilation (PCV) valve and vacuum tube.
  10.  
  11. Disengage the wiring harness at the rocker arm cover including the connections for:
    1. Air conditioning compressor clutch (if equipped).
    2.  
    3. Coolant temperature sensor.
    4.  
    5. Manifold Absolute Pressure (MAP) sensor.
    6.  
    7. Throttle Position (TP) sensor.
    8.  
    9. Exhaust Gas Recirculation (EGR) solenoid.
    10.  
    11. Fuel injector(s).
    12.  
    13. Ignition coil.
    14.  
    15. Knock sensor module.
    16.  
    17. Wiring harness ground at the coolant outlet.
    18.  

  12.  
  13. Tag and disconnect the vacuum tubes from the MAP sensor and EGR solenoid. Remove the sensor bracket.
  14.  
  15. Remove the rocker arm cover-to-cylinder head bolts, then remove the cover and gasket.
  16.  
  17. Using a plastic scraper, clean the gasket mounting surfaces.
  18.  

To install:
  1. Using a new gasket, install the rocker cover and tighten the retainers to 90 inch lbs. (10 Nm).
  2.  
  3. Install the sensor bracket, then connect the vacuum tubes to the MAP sensor and EGR solenoid, as tagged during removal.
  4.  
  5. Engage the wiring harness connectors to the components disengaged earlier.
  6.  
  7. Install the PCV valve and vacuum tube.
  8.  
  9. Connect the spark plug wires to the clip at the rear of the cylinder head and to the side of the cylinder head.
  10.  
  11. Install the air cleaner, adapter and heat stove tube.
  12.  
  13. Connect the negative battery cable.
  14.  
  15. Start the engine and check for leaks.
  16.  
  17. Once the engine has cooled sufficiently, install the engine cover to the passenger compartment.
  18.  

RIGHT SIDE (1996)
  1. Disconnect the negative battery cable for safety.
  2.  
  3. From inside the vehicle, remove the engine cover. For details, please refer to General Information & Maintenance of this information.
  4.  
  5. Disconnect the spark plug wires from the brackets. If any of the wires will interfere with cover removal, they should be TAGGED and disconnected from the spark plugs for additional clearance.
  6.  
  7. Disconnect the vent tube.
  8.  
  9. Remove the purge solenoid and bracket from the engine.
  10.  
  11. Disengage the wiring harness at the rocker arm cover, then remove the bracket.
  12.  
  13. Remove the rocker arm cover-to-cylinder head bolts, then remove the cover and gasket.
  14.  
  15. Using a plastic scraper, clean the gasket mounting surfaces.
  16.  

To install:
  1. Using a new gasket, install the rocker cover and tighten the retainers to 90 inch lbs. (10 Nm).
  2.  
  3. Install the bracket and engage the wiring harness connectors at the valve cover.
  4.  
  5. Install the purge solenoid and bracket.
  6.  
  7. Connect the vent tube.
  8.  
  9. Connect the spark plug wires. If any wires were removed from the plugs, be sure to connect them as tagged during removal.
  10.  
  11. Connect the negative battery cable.
  12.  
  13. Start the engine and check for leaks.
  14.  
  15. Once the engine has cooled sufficiently, install the engine cover to the passenger compartment.
  16.  

LEFT SIDE (1985-92)
  1. Disconnect the negative battery cable for safety.
  2.  
  3. From inside the vehicle, remove the engine cover. For details, please refer to General Information & Maintenance of this information.
  4.  
  5. Remove the air cleaner.
  6.  

If equipped with a carburetor, remove the vacuum pipe from the carburetor.

  1. Disconnect the electrical harness from the rocker arm cover and any vacuum hoses (if necessary).
  2.  
  3. On late-model vehicles, remove the oil fill tube if necessary for clearance.
  4.  
  5. If necessary, disconnect the accelerator and the detent cables from the carburetor/throttle body, then remove the mounting brackets from the intake manifold.
  6.  
  7. Remove the rocker arm cover-to-cylinder head bolts and the cover.
  8.  
  9. Using a plastic scraper, clean the gasket mounting surfaces.
  10.  

To install:
  1. Install the cover using a new gasket, then tighten the rocker cover-to-cylinder head bolts to 90 inch lbs. (10 Nm).
  2.  
  3. If removed, connect and install the mounting bracket, accelerator and the detent cables to the carburetor/throttle body.
  4.  
  5. If removed, install the oil fill tube.
  6.  
  7. Connect the electrical harness to the rocker arm cover and any vacuum hoses (if necessary).
  8.  
  9. Install the air cleaner.
  10.  
  11. Connect the negative battery cable.
  12.  
  13. Start the engine and check for leaks.
  14.  
  15. Once the engine has cooled sufficiently, install the engine cover to the passenger compartment.
  16.  

LEFT SIDE (1993-95)
  1. Disconnect the negative battery cable for safety.
  2.  
  3. From inside the vehicle, remove the engine cover. For details, please refer to General Information & Maintenance of this information.
  4.  
  5. Remove the air cleaner, adapter and heat stove tube.
  6.  
  7. Remove the multiple ribbed serpentine drive belt.
  8.  
  9. If equipped, remove the air conditioning compressor pencil braces at the rear of the compressor, then remove the compressor mounting bolts. Pull the compressor forward without disconnecting or damaging the refrigerant lines.
  10.  
  11. If equipped, disconnect the vacuum tube and disengage the wiring harness connector from the cruise control servo.
  12.  
  13. Remove the oil fill tube.
  14.  
  15. Disconnect the spark plug wire bracket from the side of the cylinder head.
  16.  
  17. Remove the rocker arm cover-to-cylinder head bolts, then remove the cover and gasket.
  18.  
  19. Using a plastic scraper, clean the gasket mounting surfaces.
  20.  

To install:
  1. Using a new gasket, install the rocker cover and tighten the retainers to 90 inch lbs. (10 Nm).
  2.  
  3. Install the oil fill tube.
  4.  
  5. If equipped, engage the wiring harness and connect the vacuum tube to the cruise control servo.
  6.  
  7. If equipped, reposition the air conditioning compressor, then install and tighten the mounting bolts and the pencil braces.
  8.  
  9. Install the serpentine drive belt.
  10.  
  11. Install the air cleaner, adapter and heat stove tube.
  12.  
  13. Connect the negative battery cable.
  14.  
  15. Start the engine and check for leaks.
  16.  
  17. Once the engine has cooled sufficiently, install the engine cover to the passenger compartment.
  18.  

LEFT SIDE (1996)
  1. Disconnect the negative battery cable for safety.
  2.  
  3. From inside the vehicle, remove the engine cover. For details, please refer to General Information & Maintenance of this information.
  4.  
  5. Remove the air cleaner box and intake duct.
  6.  
  7. Remove the PCV valve and oil fill tube.
  8.  
  9. Remove the serpentine drive belt.
  10.  
  11. If equipped, unbolt the the air conditioning compressor and bracket, then slide the assembly forward without disconnecting or damaging the refrigerant lines.
  12.  
  13. Remove the EGR tube.
  14.  
  15. Disconnect the spark plug wires from the brackets. If any of the wires will interfere with cover removal, they should be TAGGED and disconnected from the spark plugs for additional clearance.
  16.  
  17. Remove the rocker arm cover-to-cylinder head bolts, then remove the cover and gasket.
  18.  
  19. Using a plastic scraper, clean the gasket mounting surfaces.
  20.  

To install:
  1. Using a new gasket, install the rocker cover and tighten the retainers to 90 inch lbs. (10 Nm).
  2.  
  3. Connect the spark plug wires. If any wires were removed from the plugs, be sure to connect them as tagged during removal.
  4.  
  5. Install the EGR tube.
  6.  
  7. If equipped, reposition the air conditioning compressor and bracket, then secure using the retainers.
  8.  
  9. Install the serpentine drive belt.
  10.  
  11. Install the PCV valve and the oil fill tube.
  12.  
  13. Install the air cleaner box and intake duct.
  14.  
  15. Connect the negative battery cable.
  16.  
  17. Start the engine and check for leaks.
  18.  
  19. Once the engine has cooled sufficiently, install the engine cover to the passenger compartment.
  20.  

 
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