Nissan Frontier, Xterra 1998-05

Timing Chain & Sprockets

Print

Removal & Installation



2.4L Engine
  1. Before servicing the vehicle, refer to the Precautions Section.
  2.  
  3. Drain the cooling system.
  4.  
  5. Drain the engine oil.
  6.  
  7. Set the engine to Top Dead Center (TDC) of the compression stroke for the No. 1 cylinder.
  8.  
  9. Remove or disconnect the following:

    Negative battery cable
     
    Air cleaner assembly
     
    Spark plug wires
     
    Cooling fan and shroud
     
    Distributor
     
    Valve cover
     
    Accessory drive belts
     
    Power steering pump and brackets
     
    A/C compressor and bracket
     
    Idler pulleys
     
    Water pump pulley
     
    Crankshaft pulley
     
    Front crankshaft seal
     
    Oil pump and drive spindle
     
    Oil pan
     
    Upper timing cover
     
    Lower timing cover
     
    Upper timing chain tensioner
     
    Upper timing chain and camshaft sprockets. Matchmark the timing chain to the sprockets.
     
    Lower timing chain tensioner
     
    Lower timing chain and idler sprocket. Matchmark the timing chain to the sprockets.
     

  10.  

To install:

Click image to see an enlarged view

Fig. Lower timing chain alignment-2.4L engine



Click image to see an enlarged view

Fig. Upper timing chain alignment-2.4L engine

  1. Install or connect the following:

    Lower timing chain and idler sprocket with the timing marks aligned as shown. Tighten the idler sprocket bolt to 48-61 ft. lbs. (66-83 Nm).
     
    Lower timing chain tensioner. Tighten the bolts to 56-66 inch lbs. (6.5-7.5 Nm).
     
    Upper timing chain and camshaft sprockets with the timing marks aligned as shown. Tighten the camshaft sprocket bolts to 123-130 ft. lbs. (167-177 Nm).
     
    Upper timing chain tensioner. Tighten the bolts to 56-66 inch lbs. (6.5-7.5 Nm).
     
    Lower timing cover. Tighten the large bolts to 12-14 ft. lbs. (16-19 Nm) and the small bolts to 56-66 inch lbs. (6.5-7.5 Nm).
     
    Upper timing cover. Tighten the large bolts to 12-14 ft. lbs. (16-19 Nm) and the small bolts to 56-66 inch lbs. (6.5-7.5 Nm).
     
    Oil pan
     
    Oil pump and drive spindle
     
    Front crankshaft seal
     
    Crankshaft pulley. Tighten the bolt to 105-112 ft. lbs. (142-152 Nm).
     
    Water pump pulley
     
    Idler pulleys
     
    A/C compressor and bracket
     
    Power steering pump and brackets
     
    Accessory drive belts
     
    Valve cover
     
    Distributor
     
    Cooling fan and shroud
     
    Spark plug wires
     
    Air cleaner assembly
     
    Negative battery cable
     

  2.  
  3. Fill the cooling system.
  4.  
  5. Fill the crankcase to the correct level.
  6.  
  7. Start the engine and check for leaks.
  8.  
  9. Check the ignition timing and adjust, as necessary.
  10.  

2.5L Engine


Click image to see an enlarged view

Fig. Timing chain and related components-2.5L engine

  1. Before servicing the vehicle, refer to the Precautions Section.
  2.  
  3. Properly relieve the fuel system pressure.
  4.  
  5. Disconnect the negative battery cable.
  6.  
  7. Remove the air cleaner and the air duct assembly.
  8.  
  9. Remove the spark plugs.
  10.  
  11. Remove the intake manifold.
  12.  
  13. Disconnect the PCV hose from the rocker cover. Remove the ignition coil.
  14.  
  15. Remove the PCV valve and O-ring from the rocker cover, if necessary.
  16.  
  17. Remove the oil filler cap from the rocker cover, if necessary.
  18.  
  19. Remove the rocker cover retaining bolts. Be sure to remove the bolts by reversing the order of the tightening torque sequence.
  20.  
  21. Remove the rocker cover. Discard the gasket.
  22.  
  23. Remove the coolant reservoir tank. Remove the auxiliary drive belt auto-tensioner.
  24.  
  25. Remove the alternator. Remove the strut tower brace.
  26.  
  27. Remove the air conditioning compressor and position it to the side. Do not disconnect the refrigerant lines.
  28.  
  29. Remove the power steering pump and reservoir tank; position the assembly to the side. Do not disconnect the fluid lines.
  30.  
  31. Remove the upper and lower oil pan. Remove the strainer.
  32.  
  33. Remove the IVT control cover bolts. Be sure to remove the bolts by reversing the order of the tightening torque sequence.
  34.  
  35. Remove the cover by cutting the sealant using tool KV10111100 (J-37228) or equivalent.
  36.  
  37. Position the number one cylinder on its compression stroke by rotating the crankshaft pulley clockwise. Align the mating marks for TDC with the timing indicator on the front cover.
  38.  
  39. At the same time make sure that the mating marks on the camshaft sprockets are lined up as indicated in the illustration. If not rotate the crankshaft one more turn to line up the mating marks.

    Click image to see an enlarged view

    Fig. Timing chain alignment marks-2.5L engine

  40.  
  41. Hold the crankshaft pulley with a suitable tool. Loosen the crankshaft pulley retaining bolt.
  42.  
  43. Pull the pulley out about 0.39 inch. Remove the crankshaft pulley bolt.
  44.  
  45. Attach a pulley puller in the M6 thread hole on the crankshaft pulley. Remove the crankshaft pulley.
    NOTE
    Be careful not to damage the front cover and/or the crankshaft.

  46.  
  47. Loosen the front cover retaining bolts, in the order indicated in the bolt loosening sequence illustration. Remove the front cover. Be careful not to damage the mating surfaces.

    Click image to see an enlarged view

    Fig. Front cover bolt removal sequence-2.5L engine

  48.  
  49. Using a seal removal tool, remove the oil seal, as required.
  50.  
  51. To remove the timing chain, push in on the chain tensioner plunger. Insert a stopper pin into the hole on the chain tensioner body to secure the chain tensioner plunger. Remove the chain tensioner. Remove the chain. Do not rotate the crankshaft with the chain removed.
    NOTE
    Use a 0.02 inch (approximate) metal pin as a stopper pin.

  52.  
  53. Remove the camshaft sprockets.
  54.  
  55. Remove the timing chain slack guide, timing chain tensioner guide and spacer.
  56.  
  57. Remove the balancer unit timing chain tensioner by lifting the lever up and releasing the ratchet claw for return proof. Push the tensioner sleeve in and hold it. Matching the hole on the lever with the one on the body, insert a stopper pin to secure the tensioner sleeve. Remove the balancer unit timing chain tensioner.
    NOTE
    Use a 0.04 inch (approximate) metal pin as a stopper pin.



    Click image to see an enlarged view

    Fig. Balance unit stopper pin installation-2.5L engine

  58.  
  59. Secure the hexagonal portion of the balancer shaft using a suitable tool. Loosen the balancer unit sprocket bolt.
  60.  
  61. Remove the balancer unit timing chain, balancer unit sprocket and crankshaft sprocket.
    NOTE
    When removing the balancer unit timing chain, remove the crankshaft sprocket and balancer unit sprocket at the same time.

  62.  
  63. Loosen the balancer unit mounting bolts, in the order of the tightening sequence. Remove the balancer unit. Do not disassemble the balancer unit. Bolts one and four use a E14 torx head socket.
  64.  

To install:

  1. Check the chain for cracks and excessive wear, replace as required.
  2.  
  3. Measure the balancer unit bolt outer diameters (-d1- and -d2-) at two positions, as shown in the illustration. If reduction appears in the -A- range, regard it as -d2-. Specification is as follows: (-d1- - -d2-): 0.0059 inch. If it exceeds the specification (large difference in dimensions) replace the balancer unit bolt with a new one.

    Click image to see an enlarged view

    Fig. Balance unit bolt measurement-2.5L engine

  4.  
  5. Measure the balancer bolt unit length. If it exceeds the specification replace the balancer unit bolt with a new one. Specification is 6.974 inch.

    Click image to see an enlarged view

    Fig. Timing chain alignment-2.5L engine

  6.  
  7. Make sure that the crankshaft key is pointing straight up. Install the O-ring to the balancer unit.
  8.  
  9. Install the balancer unit. Torque the bolts to specification and in the proper sequence using tool KV10112100 (BT8653-A) or equivalent.
    NOTE
    Check the tightening angle using a tool or a protractor. Do not make a judgment by visual check alone.

    1. Step 1: bolts 1-4 to 35 ft. lbs.
    2.  
    3. Step 2: bolts 1-4 100 degrees clockwise
    4.  
    5. Step 3: bolts 1-4 loosen in the reverse order of the tightening sequence to zero
    6.  
    7. Step 4: bolts 1-4 to 35 ft. lbs.
    8.  
    9. Step 5: bolts 1-4 100 degrees clockwise
    10.  
    11. Step 6: bolts 5-6 to 22 ft. lbs.
    12.  



    Click image to see an enlarged view

    Fig. Balance unit bolt torque sequence-2.5L engine

  10.  
  11. Install the crankshaft sprocket, balancer unit sprocket and balancer timing chain.
  12.  
  13. Make sure that the crankshaft sprocket is positioned with the mating marks on the cylinder block and crankshaft sprocket meeting at the top.
  14.  
  15. Install it by aligning the mating marks on each sprocket and balancer unit timing chain.
  16.  
  17. Secure the hexagonal portion of the balancer shaft using a suitable tool. Tighten the balancer unit sprocket bolt to specification.
    NOTE
    Install the crankshaft sprocket, balancer unit sprocket and balancer unit timing chain at the same time.

  18.  
  19. Install the balancer unit timing chain tensioner.
    NOTE
    After installation, make sure that the mating marks have not slipped. Remove the stopper pin and release the tensioner sleeve.

  20.  
  21. Align the mating marks on each sprocket and timing chain. Install the timing chain and related parts.
  22.  
  23. Before and after installing the chain tensioner, check again to be sure that the mating marks have not slipped.
  24.  
  25. After installing the chain tensioner, remove the stopper pin. Make sure that the tensioner moves freely.
    NOTE
    After the mating marks are aligned, keep them aligned by holding them with your hand. To avoid skipped teeth, do not rotate the crankshaft and camshaft until the cover is installed.


    NOTE
    Before installing the chain tensioner, it is possible to change the position of the mating mark on the timing chain for that on each sprocket for alignment.

  26.  
  27. Install the front cover oil seal. Install O-rings to the cylinder head and the cylinder block,
  28.  
  29. Apply a continuous bead of liquid gasket to the front cover. Be sure to use genuine RTV sealant, or equivalent.
    NOTE
    Sealant application instructions differ depending on position, refer to the illustration for positioning. Detail -A-, cross over the start of the application and the end. Detail -B-, apply liquid gasket outside of the bolt holes. For all bolt holes other than -B-, apply to the inside. Detail -C-, between here only, apply a bead of sealant 0.177-0.217 inch diameter.



    Click image to see an enlarged view

    Fig. Front cover sealant application with respect to positioning-2.5L engine

  30.  
  31. Make sure that the mating marks of the chain and each sprocket are still aligned.
  32.  
  33. Install the front cover. Torque the retaining bolts to specification and in the proper sequence. Bolt position 5, 10, 14 and 17: 45mm (1.77 inch). Except the above (except 1 to 4): 20mm (0.79 inch).
    NOTE
    Be sure to wipe off any excess liquid gasket leaking to the surface for installing the oil pan.

    1. M6 bolts: 9 ft. lbs.
    2.  
    3. M10 bolts: 36 ft. lbs.
    4.  
    5. After all bolts are tightened, retighten them to specification and in the proper sequence
    6.  



    Click image to see an enlarged view

    Fig. Front cover bolt torque sequence-2.5L engine

  34.  
  35. Install the chain guide between the camshaft sprockets.
  36.  
  37. Install the oil rings to the camshaft sprocket (INT) insertion points on backside of the intake valve timing control cover. Install the O-ring to the front cover.
  38.  
  39. Apply a continuous bead of liquid gasket, 0.122 inch in diameter, to the front cover. Be sure to use genuine RTV sealant, or equivalent.
  40.  
  41. Install the cover. Tighten the bolts in the proper sequence to specification.
  42.  
  43. Install the intake valve timing control solenoid valve to the intake valve timing control cover, if removed.
  44.  
  45. Connect the ground cables, and install the harness clip.
  46.  
  47. Install the crankshaft pulley. Torque the retaining bolt to specification.
  48.  
  49. When installing the rocker cover, apply liquid gasket, be sure to use genuine RTV silicone sealant or equivalent, to the positions shown in the illustration. Refer to figure -a- to apply liquid gasket to joint part of camshaft bracket No.1 and cylinder head. Refer to figure -b- to apply liquid gasket in 90 degrees to figure -b-.
  50.  
  51. Install the rocker cover. Torque the retaining bolts to 18 inch lbs and than to 73 inch lbs, in the proper sequence.
  52.  
  53. Continue the installation in the reverse order of the removal procedure.
    NOTE
    If hydraulic pressure inside the timing chain tensioner drops after removal/installation, slack in the guide may generate a pounding noise during and just after engine start. This is normal the noise will stop after hydraulic pressure rises.

  54.  

4.0L Engine


Click image to see an enlarged view

Fig. Timing chain and related components-4.0L engine


NOTE
The procedure below describes the removal and installation of the front timing case and timing chain related parts and rear timing chain case, when the upper oil pan needs to be removed or installed. When only the timing chain (primary) is being removed it is not necessary to remove the rocker covers.

  1. Before servicing the vehicle, refer to the Precautions Section.
  2.  
  3. Properly relieve the fuel system pressure.
  4.  
  5. Disconnect the negative battery cable.
  6.  
  7. Remove the engine cover. Drain the engine oil. Drain the engine coolant.
  8.  
  9. Remove the upper and lower oil pans.
  10.  
  11. Remove the radiator cooling fan assembly. Remove the drive belts.
  12.  
  13. Separate the engine wiring harnesses by removing their brackets from the front timing chain case.
  14.  
  15. Remove the power steering pump from the bracket with the fluid hoses attached. Position the assembly to the side. Do not disconnect the hoses. Remove the bracket.
  16.  
  17. Remove the alternator. Remove the water bypass hose, water hose clamp and idler pulley bracket from the front timing chain case.
  18.  
  19. Remove the left and right intake valve timing control covers. Loosen the bolts in the reverse order of the tightening sequence. Use tool KV10111100 (J-37228) or equivalent to cut the liquid gasket seal.
    NOTE
    The shaft is internally jointed with the camshaft sprocket (INT) center hole. When removing, keep it horizontal until it is completely disconnected.

  20.  
  21. Remove the collared O-rings from the front timing chain case on both the left and right side.
  22.  
  23. Remove the intake manifold collector.
  24.  
  25. Separate the engine harness and remove their brackets from the rocker covers. Remove the harness bracket from the cylinder head, if necessary.
  26.  
  27. Remove the ignition coil. Remove the PCV hoses. Remove the oil filler cap, if necessary.
  28.  
  29. Loosen the rocker cover retaining bolts, in the reverse order of the tightening sequence.
  30.  
  31. Remove the rocker covers from the engine.
    NOTE
    When only the timing chain (primary) is being removed it is not necessary to remove the rocker covers.

  32.  
  33. Set the No.1 cylinder at TDC of its compression stroke by rotating the crankshaft pulley clockwise to align the timing mark (grooved line without color) with the timing indicator. Make sure that the intake and exhaust cam noses on No.1 cylinder (engine front side on right bank) are in alignment as shown in the illustration. If not, rotate the crankshaft in the clockwise direction 360 degrees.
    NOTE
    When only the timing chain (primary) is removed, the rocker cover does not need to be removed. To be sure that the No.1 cylinder is set at TDC on the compression stroke, remove the front timing chain case cover first, then check the mating marks on the camshaft sprockets.

  34.  
  35. Remove the starter. Position tool KV10117700 (J-44716) or equivalent.
  36.  
  37. Loosen the crankshaft pulley retaining bolt and locate the bolt seating surface, which is about 0.39 inch from its original position.
    NOTE
    Do not remove the crankshaft pulley bolt. Keep the loosened pulley bolt in place to protect the removed crankshaft pulley from dropping.

  38.  
  39. Pull the pulley with both hands and remove it from its mounting. Remove the bolt and pulley from the engine.
  40.  
  41. Loosen and remove the two bolts of the upper oil pan.
  42.  
  43. Loosen the front timing chain cover retaining bolts in the reverse order of the tightening sequence.
  44.  
  45. Insert a suitable tool in the notch at the top of the front timing chain case and pry off the case by moving the tool as shown in the illustration. Use tool KV10111100 (J-37228) or equivalent to cut the liquid gasket seal.
    NOTE
    Do not use a screwdriver or something similar. After removal handle the front timing chain cover case carefully so it does not tilt, cant or warp under a load.



    Click image to see an enlarged view

    Fig. Tool installation and location-4.0L engine

  46.  
  47. Remove the O-rings from the rear timing chain case.
  48.  
  49. Remove the water pump cover and chain tensioner cover from the front timing chain case cover, as required.
  50.  
  51. Remove the oil seal from the front timing chain case cover, as required.
  52.  
  53. Remove the timing chain tensioner (primary) by loosening the clip of the timing chain tensioner (primary) and release the plunger stopper. Insert the plunger into the tensioner body by pressing the slack guide. Keep the slack guide pressed and hold the plunger in by pushing the stopper pin through the tensioner body hole and the plunger groove. Remove the bolts and remove the timing chain tensioner (primary).

    Click image to see an enlarged view

    Fig. Timing chain tensioner (primary)-4.0L engine

  54.  
  55. Remove the internal chain guide, tension guide and slack guide.
    NOTE
    The tension guide can be removed after removing the timing chain (primary).

  56.  
  57. Remove the timing chain (primary) and the crankshaft sprocket.
    NOTE
    After removing the timing chain (primary), do not turn the crankshaft and camshaft separately or the valves will strike the piston heads.

  58.  
  59. To remove the timing chain (secondary) and camshaft sprockets, attach a suitable stopper pin to the right and left timing chain tensioner (secondary).
    NOTE
    Use a 0.02 inch (approximate) metal pin as a stopper pin.

  60.  
  61. Remove the camshafts. Remove the valve lifters. Identify them for reinstallation in their original locations.
  62.  
  63. Remove the camshaft sprocket (INT and EXH) bolts. Secure the hexagonal portion of the camshaft using a wrench to loosen the bolts.
    NOTE
    Do not loosen the bolts with securing anything other than the camshaft hexagonal portion or with tensioning the timing chain.

  64.  
  65. To remove the timing chain (secondary) together with the camshaft sprockets, turn the crankshaft slightly to secure slackness of the timing chain on the timing chain tensioner (secondary) side.
  66.  
  67. Insert a 0.020 inch thick metal or resin plate between the timing chain and timing chain plunger (guide). Remove the timing chain (secondary) together with the camshaft sprockets with the timing chain loose from the guide groove.
    CAUTION
    Be careful of the plunger coming off when removing the timing chain (secondary). This is because the plunger of the timing chain tensioner (secondary) moves during operation, leading to coming off its fixed stopper pin.


    NOTE
    The camshaft sprocket (INT) is a one piece integrated design sprocket for the timing chain (primary) and for the timing chain (secondary). When handling the sprocket avoid shock to the sprocket. Do not disassemble or loosen bolt -A-, as shown in the illustration.



    Click image to see an enlarged view

    Fig. Resin plate installation location-4.0L engine



    Click image to see an enlarged view

    Fig. Camshaft sprocket bolt location-4.0L engine

  68.  
  69. Remove the rear timing chain case cover bolts, in the reverse order of the tightening sequence. Using the proper tool cut the liquid gasket sealant seal. Remove the cover.
    NOTE
    Do not remove the metal cover of the oil passage. After removal handle the case carefully so it does not tilt, or warp under a load.



    Click image to see an enlarged view

    Fig. Metal cover plate location on rear timing case cover-4.0L engine

  70.  
  71. Remove the O-rings from the cylinder head and No.1 camshaft bracket. Remove the O-rings from the cylinder block.
  72.  
  73. If necessary, remove the timing chain tensioners (secondary) from the cylinder head by first removing the No.1 camshaft bracket. Remove the timing chain tensioners (secondary) with the stopper pin attached.
  74.  

To install:

Click image to see an enlarged view

Fig. Timing chain alignment-4.0L engine

  1. Check the chain for cracks and excessive wear, replace as required.
  2.  
  3. Be sure to remove all old gasket material from bolts and bolt holes.
  4.  
  5. If removed install the timing chain tensioners (secondary) to the cylinder head.
  6.  
  7. Install camshaft brackets No.1.
  8.  
  9. To install the rear timing chain case cover, first install new O-rings to the cylinder block, Install new O-rings to the cylinder head and camshaft bracket No.1.
  10.  
  11. Apply liquid gasket sealant to the rear timing chain case back side, as shown in the illustration. Be sure to use genuine RTV sealant, or equivalent.
    NOTE
    For -A- in the figure, completely wipe out excessive liquid gasket extended on a portion touching at engine coolant. Apply liquid gasket on the installation position of the water pump and cylinder head very completely.



    Click image to see an enlarged view

    Fig. Rear timing chain cover sealant application-4.0L engine

  12.  
  13. Align the rear timing case with dowel pins (right and left) on the cylinder block. Install the rear timing chain case. Make sure that the O-rings stay in place during installation to the cylinder block, cylinder head and camshaft bracket No.1.
  14.  
  15. Tighten the bolts to specification and in the proper sequence.
    NOTE
    Be sure to wipe off any excess liquid gasket leaking to the surface for installing the oil pan.

    1. Bolt length: 0.79 inch. Bolt position: 1,2,3,6,7,8,9,and 10.
    2.  
    3. Bolt length: 0.63 inch. Bolt position: except 1,2,3,6,7,8,9,and 10.
    4.  
    5. Torque bolts to 9 ft. lbs.
    6.  
    7. After all bolts are tightened, retighten them to specification and in the proper sequence
    8.  



    Click image to see an enlarged view

    Fig. Rear timing chain cover bolt torque sequence-4.0L engine

  16.  
  17. After installing the rear timing case, check the surface height deference between the rear timing chain case and the lower cylinder block. Specification should be -0.0094-0.0055 inch. If not within specification, repeat the installation procedure.

    Click image to see an enlarged view

    Fig. Checking surface height-4.0L engine

  18.  
  19. Install the water pump, using new O-rings.
  20.  
  21. Make sure that the dowel pin hole, dowel pin of camshaft and crankshaft key are located with number one piston at TDC on the compression stroke.
    NOTE
    Though the camshaft does not stop at the position, as shown in the illustration, for placement of the cam nose it is generally accepted that the camshaft is placed for the same direction as the illustration. Camshaft dowel pin hole (intake side): at the cylinder head upper face side in each bank. Camshaft dowel pin hole (exhaust side): at the cylinder head upper face side in each bank. Crankshaft key: at the cylinder head side of the right bank. Hole on the small diameter side must be used for the intake side dowel pin hole.



    Click image to see an enlarged view

    Fig. Dowel pin and crankshaft key alignment-4.0L engine

  22.  
  23. To install the timing chains (secondary) and camshaft sprockets, push the plunger of the timing chain tensioner (secondary) and keep it pressed in with the stopper pin.
    NOTE
    Mating surfaces between the timing chain and sprockets slip easily. Confirm all mating mark positions repeatedly during the installation process.

  24.  
  25. Install the timing chains (secondary) and camshaft sprockets (INT and EXH).
  26.  
  27. Align the mating marks on the timing chain (secondary) cooper color link, with the ones on the camshaft sprockets (INT and EXH) punched and install them.
    NOTE
    Mating marks for the camshaft sprocket (INT) are on the back side of the camshaft sprocket (secondary). There are two types of mating marks, circle and oval. They should be used for the right and the left banks, respectively. Right bank: circle type. Left bank: oval type.

  28.  
  29. Align the dowel pin and pin hole on the camshafts with the groove and the dowel pin on the sprockets, and install them.
  30.  
  31. On the exhaust side, align the pin hole on the small diameter side of the camshaft front end with the dowel pin on the back side of the camshaft sprocket, and install them.
  32.  
  33. On the exhaust side, align the dowel pin on the camshaft front end with the pin groove on the camshaft sprocket, and install them.
    NOTE
    In case that the positions of each mating mark and each dowel pin will not fit on the mating marks, make a fine adjustment to the position holding the hexagonal portion on the camshaft with a wrench, or equivalent.


    NOTE
    Bolts for the camshaft sprockets must be tightened. Tightening them by hand is enough to prevent the dislocation of the dowel pins. It may be difficult to visually check the dislocation of mating marks during and after installation. To make the matching easier, make a mating mark on the top of the sprocket teeth and its extended line in advance with paint.

  34.  
  35. After confirming that the mating marks are aligned, tighten the camshaft sprocket bolts.
  36.  
  37. Pull the stopper pins out from the timing chain tensioners (secondary). Install the tension guide.
  38.  
  39. To install the timing chain (primary), install the crankshaft sprocket. Be sure that the mating marks on the crankshaft sprocket, face the front of the engine.
  40.  
  41. Install the timing chain (primary).
    NOTE
    Install the timing chain (primary) so that the mating mark punched (B) on the camshaft sprocket is aligned with the copper link (A) on the timing chain, while the mating mark notched (E) on the crankshaft sprocket (D) is aligned with the yellow link (F) on the timing chain, as shown in the illustration. If it is difficult to align mating marks (A) with (B) and (E) with (F) of the timing chain (primary) with each sprocket, gradually turn the camshaft using a wrench on the hexagonal portion to align it with the timing marks. During alignment be careful to prevent dislocation of the mating marks alignments of the timing chains (secondary). Note (G) indicates the water pump.



    Click image to see an enlarged view

    Fig. Timing chain (primary) alignment-4.0L engine

  42.  
  43. Install the internal chain guide, slack guide and timing chain tensioner (primary).
    NOTE
    Do not over tighten the slack guide bolts. It is normal for a gap to exist under the bolt seats when the bolts are tightened to specification.



    Click image to see an enlarged view

    Fig. Slack guide mounting bolt gap-4.0L engine

  44.  
  45. When installing the timing chain tensioner (primary), push in the plunger and keep it pressed in with the stopper pin. Remove any dirt on the surfaces. After installation, pull out the stopper pin by pressing the slack guide.
  46.  
  47. Make sure, again, that the mating marks on the camshaft sprockets and timing chain have not slipped out of alignment. Install new O-rings on the rear timing chain case.
  48.  
  49. Install a new front seal in the front timing chain case cover.
  50.  
  51. Install the water pump cover and chain tensioner cover to the front timing chain case cover. Apply a continuous bead of liquid gasket (0.091-0.130 inch diameter) to the front timing chain case cover before installing the water pump cover and chain tensioner cover. Be sure to use genuine RTV sealant, or equivalent.
  52.  
  53. Before installing the front timing chain case cover apply a continuous bead of liquid gasket (0.102-0.142 inch in diameter) to the front timing chain case back side, as shown in the illustration. Be sure to use genuine RTV sealant, or equivalent.

    Click image to see an enlarged view

    Fig. Front timing chain cover sealant application-4.0L engine

  54.  
  55. Install new O-rings on the rear timing chain case. To assemble the front timing chain case cover, fit the lower end of the front timing chain case tightly onto the top face of the oil pan (upper). From the fitting point, make entire front timing chain case contact rear timing chain case completely.
    NOTE
    Since the front timing chain case cover is offset for difference of holt holes, tighten the bolts temporarily while holding the front timing chain case cover from the front and the top. Now insert a dowel pin while holding the front timing chain case cover from the front and the top.

  56.  
  57. Once the cover is installed, torque the retaining bolts to specification and in the proper sequence. There are four different types of bolts.
    1. Bolt diameter: 0.39 inch. Bolt position: 1-5. Torque to 41 ft. lbs.
    2.  
    3. Bolt diameter: 0.24 inch. Bolt position: 6-25. Torque to 9 ft. lbs.
    4.  
    5. After all bolts are tightened, retighten them to specification and in the proper sequence
    6.  



    Click image to see an enlarged view

    Fig. Front timing chain cover bolt torque sequence-4.0L engine

  58.  
  59. Install the two bolts in the oil pan (upper). Torque to 16 ft. lbs.
  60.  
  61. Install new seal rings in the shaft grooves of the right and left intake valve timing control covers.
  62.  
  63. Apply a continuous bead of liquid gasket (0.083-0.122 inch in diameter) to the covers. Be sure to use genuine RTV sealant, or equivalent.
  64.  
  65. Install new collared O-rings in the front timing chain case oil hole (left and right sides). Be careful not to move the seal ring from the installation groove, align the dowel pins on the front timing chain case with the holes to install the intake valve timing control covers.
  66.  
  67. Tighten the bolts in sequence and to specification.

    Click image to see an enlarged view

    Fig. Right and left intake valve timing control cover bolt torque sequence-4.0L engine

  68.  
  69. Install the crankshaft pulley. Torque to specification
  70.  
  71. Install the upper and lower oil pans.
  72.  
  73. Install the intake manifold collector.
  74.  
  75. Before installing the rocker cover, apply liquid gasket, be sure to use genuine RTV silicone sealant or equivalent, to the positions shown in the illustration. Refer to figure -a- to apply liquid gasket to joint part of camshaft bracket No.1 and cylinder head. Refer to figure -b- to apply liquid gasket to the figure -a- squarely.
  76.  
  77. Install the rocker cover. Torque the retaining bolts to 17 inch lbs and than to 74 inch lbs, in the proper sequence.
  78.  
  79. Continue the installation in the reverse order of the removal procedure.
    NOTE
    If hydraulic pressure inside the timing chain tensioner drops after removal/installation, slack in the guide may generate a pounding noise during and just after engine start. This is normal the noise will stop after hydraulic pressure rises.

  80.  

 
label.common.footer.alt.autozoneLogo