Avalon 1995-1996

Cylinder Head

Print

Removal & Installation




CAUTION
The fuel system pressure must be relieved before disconnecting any fuel lines. Failure to do so may result in fire and/or personal injury.

  1. Before servicing the vehicle, refer to the Precautions Section.
  2.  
  3. Relieve the fuel pressure from the fuel lines.
    1. Drain the engine coolant.
    2.  

  4.  
  5. With the ignition switch in the LOCK position, disconnect the negative battery terminal. If equipped with an air bag system, wait at least 90 seconds or longer before performing any other work.
  6.  
  7. Remove the air cleaner cap assembly and air filter.
  8.  
  9. Remove the V-bank cover.

    Click image to see an enlarged view

    Fig. Engine components

  10.  
  11. Remove the air intake chamber assembly as follows:
    1. Disconnect the following connectors and cables:

      Accelerator cable
       
      Automatic transmission throttle cable
       
      Throttle Position Sensor (TPS) connector
       
      Idle Air Control (IAC) valve connector
       
      Exhaust Gas Recirculation (EGR) gas temperature sensor connector
       
      Vacuum Switching Valve (VSV) connector for the Acoustic Control Induction System (ACIS)
       
      VSV connector for the Evaporator Emissions (EVAP)
       
      VSV connector for the EGR
       
      Data Link Connector (DLC1) from the bracket on the intake air control valve
       

    2.  
    3. Remove the power steering pressure tube from the No. 1 engine hanger by removing the 2 bolts.
    4.  
    5. Disconnect the following hoses, clamps, and cables:

      Brake booster vacuum hose from the intake air control valve for the ACIS
       
      PCV hose from the PCV valve on the right-hand cylinder head
       
      Ground strap and cable from the air intake air control valve from the ACIS
       
      Ground cable from the air intake chamber
       
      Vacuum hose clamp from fuel pipe

      Click image to see an enlarged view

      Fig. Disconnect hoses, cables, and strap

       



      2 bypass hoses from the throttle body
       
      2 power steering air hoses from the air intake chamber
       
      Air assist hose from the throttle body
       
      EVAP hose from the pipe on emission control valve set
       
      2 vacuum hoses from the pipes on the cylinder head rear plate
       
      Vacuum sensing hose from the fuel pressure regulator
       
      Engine wire clamp from emission control valve set

      Click image to see an enlarged view

      Fig. Disconnect hoses and clamp

       

    6.  
    7. Remove the 2 bolts and the No. 1 engine hanger.
    8.  
    9. Remove the 2 bolts and the air intake chamber stay.
    10.  
    11. Remove the No. 2 EGR pipe and 2 gaskets by removing the 4 nuts.
    12.  
    13. Disconnect the hose from the VSV from the EVAP.
    14.  
    15. Using an 8mm hexagon wrench, remove the 2 bolts, 2 nuts, air intake chamber assembly and gasket.
    16.  

  12.  
  13. Disconnect the fuel injector connectors.
  14.  
  15. Remove the air assist hoses and pipe.
  16.  
  17. Disconnect the fuel return hose from the No. 1 fuel pipe.
  18.  
  19. Disconnect the fuel inlet hose from the fuel filter.
    NOTE
    Catch any fuel leaking from the filter in a shop rag. Dispose of the rag properly.

  20.  
  21. Remove the delivery pipes and injectors from the engine.
  22.  
  23. Remove the heater hoses from the intake manifold.
  24.  
  25. Remove the intake manifold assembly.
  26.  
  27. Remove the water outlet:
    1. Disconnect these connectors and hoses:

      ECT sender gauge connector
       
      ECT sensor connector
       
      Ground strap connector
       
      Radiator hose
       
      Engine coolant reservoir hose
       

    2.  
    3. Remove the 2 bolts, 2 nuts and 2 plate washers.
    4.  
    5. Disconnect the water bypass hose, and remove the water outlet.
    6.  
    7. Remove the 2 gaskets.
    8.  

  28.  
  29. Remove the alternator drive belt.
  30.  
  31. Remove the power steering pump.
  32.  
  33. Remove the ignition coils and spark plugs.
  34.  
  35. Remove the timing belt.
  36.  
  37. Remove the camshaft timing pulleys.

    Click image to see an enlarged view

    Fig. Timing belts and pulleys

  38.  
  39. Remove the No. 2 idler pulley.
  40.  
  41. Remove the No. 3 timing belt cover.
  42.  
  43. Disconnect the engine wire protector:
    1. Disconnect the engine wire from rear side. Remove the 2 nuts, and disconnect the engine wire protector from the right-hand cylinder head and water inlet.
    2.  
    3. Disconnect the engine wire from right-hand side. Remove the 5 nuts, and disconnect the engine wire and protector from the right-hand cylinder head.
    4.  
    5. Disconnect the engine wire from left-hand side. Remove the 2 bolts, and disconnect the engine wire protector from the left-hand cylinder head.
    6.  

  44.  
  45. Disconnect the cylinder head rear plate from the left-hand cylinder head.

    Click image to see an enlarged view

    Fig. Disconnect the vacuum hoses and remove the cylinder head rear plate

  46.  
  47. Disconnect the water inlet pipe from the water inlet. Remove the O-ring.
  48.  
  49. Remove the No 1 EGR pipe.
  50.  
  51. Remove the exhaust manifolds and the power steering pump bracket.

    Click image to see an enlarged view

    Fig. Exhaust manifolds

  52.  
  53. Remove the camshaft position sensor.
  54.  
  55. Remove the dipstick assembly.

    Click image to see an enlarged view

    Fig. Unbolt and remove the oil dipstick from the front of the engine

  56.  
  57. Remove the valve covers.
  58.  
  59. Remove the camshafts. Refer to Camshaft & Valve Lifters, Removal & Installation.

    Click image to see an enlarged view

    Fig. Camshaft and cylinder head components

  60.  
  61. Remove the 2 (1 on each head) 8mm recessed hex bolts. Loosen and remove the 8 head bolts evenly, in 3 passes, in the reverse order of the installation sequence.

    Click image to see an enlarged view

    Fig. There are bolts recessed in the cylinder heads, remove these first



    Click image to see an enlarged view

    Fig. Left side cylinder head bolt loosening sequence



    Click image to see an enlarged view

    Fig. Cylinder head bolt loosening sequence



    Click image to see an enlarged view

    Fig. Use a prybar to help separate the head from the block



    Click image to see an enlarged view

    Fig. Lift the cylinder head off the block

  62.  
  63. Remove the cylinder head gasket. With a gasket scraper, carefully remove all the old gasket material from the cylinder head and engine block surfaces.

    Click image to see an enlarged view

    Fig. Remove the old head gasket and discard



    Click image to see an enlarged view

    Fig. Scrape the old gasket material off the mating surfaces

  64.  

To install:

  1. Place the new cylinder head gasket onto the cylinder block. Place the cylinder head onto the gasket.
  2.  
  3. Coat the threads with clean engine oil and install the bolts into the cylinder head. Tighten the bolts in sequence in 3 steps to an ultimate torque of 40 ft. lbs. (54 Nm), using the proper sequence.

    Click image to see an enlarged view

    Fig. Only use a torque wrench to tighten the cylinder head bolts



    Click image to see an enlarged view

    Fig. Cylinder head tightening sequence

  4.  
  5. Tighten each bolt, in proper sequence, then an additional 90 degrees.
  6.  
  7. Coat the threads of the 2 remaining 8mm bolts with engine oil and install them. Tighten to 13 ft. lbs. (18 Nm).
  8.  
  9. Install the camshafts following the proper sequences and procedures.
  10.  
  11. Check and adjust the valves.
  12.  
  13. Apply sealant to the cylinder heads where the camshaft supports meet the cylinder heads.
  14.  
  15. Install all remaining components in reverse of removal using the diagrams for the proper torque figure.
  16.  

 
label.common.footer.alt.autozoneLogo