300M, Concorde, Intrepid, LHS, 1998-2004

Camshaft, Bearings & Lifters

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Inspection



  1. Inspect camshaft bearing journals for damage and binding. If journals are binding, check the cylinder head for damage. Also check cylinder head oil holes for clogging.
  2.  
  3. Check the cam lobe and bearing surfaces for abnormal wear and damage. Replace camshaft if defective.
    NOTE
    If camshaft is replaced due to lobe wear or damage, always replace the rocker arms.

  4.  
  5. Measure the lobe actual wear and replace camshaft if out of limit. Standard value is 0.001 in.(0.0254 mm), wear limit is 0.010 in.(0.254 mm).
  6.  

Removal & Installation




NOTE
Camshafts are removed from the rear of each cylinder head.


WARNING
Care must be taken not to nick or scratch the journals when removing the camshaft. Carefully remove the camshaft from the rear of the cylinder head.


NOTE
Care must be taken not to scrape or nick the camshaft journals when installing the camshaft into position. Lubricate camshaft bearing journals, camshaft lobes and camshaft seal with clean engine oil and install camshaft into cylinder head.

2.7L Engine
  1. Before servicing the vehicle, refer to the Precautions section.
    WARNING
    When the timing chain is removed and the cylinder heads are installed, DO NOT turn the crankshaft or camshaft without first locating the proper crankshaft position. Failure to do so will result in piston-to-valve contact.

  2.  
  3. Remove or disconnect the following:

    Primary timing chain
     
    Second chain tensioner mounting bolts
     

  4.  
  5. Slowly loosen the camshaft bearing cap retaining bolts in the reverse order of the tightening sequence.

    Bearing caps
     
    Camshafts, secondary chain and tensioner as an assembly
     
    Tensioner and chain from the crankshaft
     

  6.  

To install:

Click image to see an enlarged view

Fig. Camshaft bearing cap tightening sequence-2.7L engine



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Fig. Exploded view of the camshaft (secondary) chain tensioner, early build-2.7L engine



Click image to see an enlarged view

Fig. Fabricate a lockpin, as shown, to keep the tensioner compressed-2.7L engine



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Fig. Proper camshaft (secondary) chain alignment-2.7L engine

  1. Assemble the chain on the camshafts. Ensure the plated links are facing toward the front. Align the plated links to the dots on the camshaft sprockets.
    NOTE
    There are 2 different styles of camshaft (secondary) chain tensioners. The Early Build tensioners will separate into sub-components, the Later Build tensioners will not. Compress the camshaft (secondary) chain as follows:

  2.  
  3. For early build vehicles:
    1. Separate the tensioner cylinder from the tensioner housing.
    2.  
    3. Carefully drain the oil from the housing using care not to remove the internal tensioner components.
    4.  
    5. Assemble the tensioner housing.
    6.  
    7. Using hand pressure, compress and lock the tensioner using a fabricated lockpin.
    8.  

  4.  
  5. For late build vehicles:
    1. Place the tensioner in a soft-jawed vise.
    2.  
    3. Slowly compress the tensioner until the fabricated lockpin can be installed.
    4.  
    5. Remove the compressed and locked tensioner from the vise.
    6.  

  6.  
  7. Insert the compressed and locked camshaft chain tensioner in between the camshafts and chain.
  8.  
  9. Position the camshafts so that the plated links and dots are facing upward.
  10.  
  11. Install or connect the following:
    WARNING
    Ensure that the rocker arms are correctly seated and in proper positions.



    Camshafts
     



    Camshaft bearing caps and torque the bolts gradually, in sequence, to 105 inch lbs. (12 Nm)
     
    Secondary chain tensioner and torque the bolts to 105 inch lbs. (12 Nm)
     
    Primary timing chain
     
    Negative battery cable
     

  12.  
  13. Remove the lockpin from the secondary chain tensioner.
  14.  

3.2L & 3.5L Engines

Camshafts are serviced from the rear of the cylinder head. Although the engine does not need to be removed for camshaft service, the cylinder head must be removed from the vehicle. Note too, that the camshaft sprockets have a D-shaped hole that allows it to rotate several degrees in each direction on its shaft.

  1. Before servicing the vehicle, refer to the Precautions section.
  2.  
  3. Properly relieve the fuel system pressure.
  4.  
  5. Drain the cooling system.
  6.  
  7. Remove or disconnect the following:
    NOTE
    Mark the timing belt rotation direction for installation. Align the timing belt sprockets with marks on the rear timing belt covers before removing the timing belt.


    NOTE
    Be sure to clean the gasket mating surfaces between the exhaust manifold and the cylinder head.



    Negative battery cable
     
    Radiator/cooling fan assemblies and the accessory drive belts
     
    Crankshaft damper and the timing belt covers
     



    Timing belt tensioner and timing belt. Refer to the appropriate section for the removal and installation procedure.
     
    Camshaft timing belt sprockets
     
    Intake manifold assembly using the recommended procedure
     
    Exhaust manifold
     

  8.  
  9. The rear timing belt cover must be removed to remove the cylinder heads. Remove the rear timing belt cover-to-cylinder head bolts. Remove the rear timing belt covers.
    NOTE
    The right-hand side timing belt cover has O-rings located behind it for the water pump passages.

  10.  
  11. Remove the cylinder head bolts and cylinder head.
    NOTE
    Mark the rocker arm assembly to note component locations before disassembly.

  12.  
  13. Remove the rocker arm and shaft assemblies.
  14.  
  15. Remove the rear camshaft cover and O-ring.
    WARNING
    Carefully, remove the camshaft from the rear of the head taking care not to nick or scratch the journals.

  16.  
  17. Inspect camshaft journals for wear or damage. If wear is present, inspect the cylinder head for damage. Inspect the head oil holes for clogging. Replace the camshaft as required.
  18.  
  19. Measure the height of the cam using a micrometer. Measure in 2 places: the unworn area and in the wear zone. Subtract the figures to get cam wear. The standard specification is 0.001 in. (0.0254mm) with the wear limit being 0.010 in. (0.254mm). Replace the camshaft if it is worn beyond this specification.
  20.  

To install:

Click image to see an enlarged view

Fig. Rocker arm/shaft tightening sequence-3.5L engines

  1. Lubricate the camshaft journals and lobes with clean engine oil.
  2.  
  3. Install or connect the following:
    WARNING
    New head bolts are recommended.


    WARNING
    Be sure that once they are all installed, the timing of the camshaft(s) is accurate.



    Camshaft
     
    Camshaft cover and O-ring and torque the bolts to 21 ft. lbs. (28 Nm)
     
    Rocker arm assemblies
     
    Cylinder head assembly
     



    Rear timing belt covers
     
    Timing belt sprocket, timing belt and timing belt tensioner. Refer to the appropriate section for the removal and installation procedure.
     



    Exhaust manifold with new gasket
     
    Intake manifold assembly
     
    Timing belt covers and crankshaft damper
     
    Accessory drive belts and set them to the proper tension
     
    Radiator and cooling fan assembly
     
    Negative battery cable
     

  4.  
  5. Fill and bleed the cooling system. An oil and filter change is recommended.
  6.  

 
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