Jeep Wagoneer/Commando/Cherokee 1984-1998

Cylinder Head

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Removal & Installation



It is important to note that each engine has its own head bolt torque sequence and tightening specification. Incorrect tightening procedure may cause head warpage and compression loss.

2.1L Diesel Engine

See Figures 1, 2, 3, 4, 5, 6 and 7

  1. Disconnect the negative battery cable.
  2.  
  3. Remove the intake manifold. Remove the exhaust manifold.
  4.  
  5. Remove the rocker arm cover. Drain the engine coolant. Remove the timing belt cover.
  6.  


CAUTION
When draining the coolant, keep in mind that cats and dogs are attracted by ethylene glycol antifreeze, and are quite likely to drink any that is left in an uncovered container or in puddles on the ground. This will prove fatal in sufficient quantity. Always drain the coolant into a sealable container. Coolant should be reused unless it is contaminated or several years old.

  1. Install sprocket holding tool MOT-854 or equivalent and remove the camshaft sprocket retaining bolt. Remove the special tool.
  2.  



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Fig. Fig. 1: Sprocket holding tool installed

  1. Loosen the bolts and move the tensioner away from the timing belt. Retighten the tensioner bolts.
  2.  
  3. Remove the timing belt from the sprockets.
  4.  

If it is necessary to remove the fuel injection pump sprocket use special tool BVI-28-01 or BVI-859 to accomplish this procedure.

  1. Disconnect the fuel pipe fittings from the injectors. Plug them in order to prevent dirt from entering the system.
  2.  
  3. Disconnect the fuel pipe fittings from the fuel injection pump. Plug them in order to prevent dirt from entering the system.
  4.  
  5. Remove the fuel pipes from their mountings on the engine. Remove all hoses and connectors from the fuel injection pump.
  6.  
  7. Remove the injection pump retaining bolts. Remove the fuel injection pump and its mounting brackets, as an assembly, from the vehicle.
  8.  
  9. Remove the retaining bolts and nuts from the cylinder head. Loosen pivot bolt but do not remove it. Remove the remaining cylinder head bolts.
  10.  



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Fig. Fig. 2: Head bolts (F), nuts (G) and pivot bolt (H)

  1. Place a block of wood against the cylinder head and tap it with a hammer in order to loosen the cylinder head gasket. The pivot movement will be minimal due to the small clearance between the studs and the cylinder head. Remove the pivot bolt from the cylinder head.
  2.  
  3. Remove the retaining bolts and the rocker arm shaft assembly from the cylinder head.
  4.  

Do not lift the cylinder head from the cylinder block until the gasket is completely loosened from the cylinder liners. Otherwise, the liner seals could be broken.

  1. Remove the cylinder head and the gasket from the engine block. While the head is off, install liner clamp tool MOT 521-01 to hold the liners in place in the block.
  2.  
  3. Clean and inspect the cylinder head thoroughly. Refer to the engine reconditioning portion outlined later in this information.
  4.  



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Fig. Fig. 3: Cylinder liner clamp tool installed

To install:
  1. Remove liner clamp tool MOT 521-01.
  2.  
  3. Position cylinder head locating tool MOT 720 on the block to insure proper alignment.
  4.  



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Fig. Fig. 4: A special tool must be used to check piston protrusion



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Fig. Fig. 5: The protrusion is measured at (A)



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Fig. Fig. 6: Head gasket thickness identification: (A) is 1.6mm (B) is 1.7mm (C) is 1.8mm

  1. Position the cylinder head and the new gasket from the engine block. Be sure that the new cylinder head gasket is positioned properly on the cylinder head and that it is the correct thickness for piston protrusion. Whenever major components, such as pistons, liners, crankshaft, etc., have been replaced, the piston protrusion must be measured to determine proper replacement head gasket thickness. Measure the protrusion as follows:
    1. Rotate the crankshaft one complete revolution clockwise and bring No. 1 piston to a point just below and before TDC.
    2.  
    3. Place thrust plate tool MOT 252-01 on top of the piston.
    4.  
    5. Assemble a dial indicator in the block gauge MOT 25101 and place this assembly on one side of the thrust plate.
    6.  
    7. Zero the indicator with the stem on the cylinder block face.
    8.  
    9. Place the stem on the top of the piston and rotate the crankshaft clockwise to TDC of the piston. Record the piston travel.
    10.  
    11. Repeat the procedure with the dial indicator on the opposite side of the block. Record the piston travel.
    12.  
    13. Add the two figures together and divide by two. Repeat the protrusion measurement for the three remaining pistons. The piston with the greatest protrusion should be the basis for determining gasket thickness. For example, if the amount of greatest piston protrusion is:

      Less than 0.96mm, use a gasket 1.6mm thick
       
      Between 0.96mm and 1.04mm, use a 1.7mm thick gasket
       
      More than 1.04mm, use a 1.8mm thick gasket
       

    14.  

  2.  
  3. Install the head bolts. Tighten the cylinder head retaining bolts to 22 ft. lbs. (30 Nm), then to 37 ft. lbs. (50 Nm), then to 70-77 ft. lbs. (95-104 Nm). Once all the bolts are tightened, recheck the torque.
  4.  



Click image to see an enlarged view

Fig. Fig. 7: Head bolt torque sequence

The cylinder head bolts must be retightened after the cylinder head is installed in the vehicle. Operate the engine for a minimum of twenty minutes. Allow the engine to cool for a minimum of two and one half hours. Loosen each cylinder head bolt in sequence about1/8turn. Then retighten in the proper sequence and tighten to 70-77 ft. lbs. (95-104 Nm). For the final tightening, tighten the bolts again, in sequence, without loosening them to 70-77 ft. lbs. (95-104 Nm).

  1. Remove tool MOT 720.
  2.  
  3. Install the rocker arm shaft assembly.
  4.  
  5. Install the fuel injection pump and its mounting brackets, as an assembly. Fuel System .
  6.  
  7. Install the fuel pipes on their mountings on the engine. Install all hoses and connectors on the fuel injection pump.
  8.  
  9. Connect the fuel pipe fittings to the fuel injection pump.
  10.  
  11. Connect the fuel pipe fittings from the injectors.
  12.  
  13. Install the timing belt.
  14.  
  15. Re-tension the timing belt.
  16.  
  17. Install the camshaft sprocket retaining bolt.
  18.  
  19. Install the valve cover.
  20.  
  21. Install the timing belt cover.
  22.  
  23. Install the intake manifold.
  24.  
  25. Install the exhaust manifold.
  26.  
  27. Fill the cooling system.
  28.  
  29. Connect the negative battery cable.
  30.  

2.5L Engine

See Figures 8, 9, 10, 11, 12, 13, 14 and 15

  1. Disconnect the battery ground.
  2.  
  3. Drain the cooling system.
  4.  


CAUTION
When draining the coolant, keep in mind that cats and dogs are attracted by ethylene glycol antifreeze, and are quite likely to drink any that is left in an uncovered container or in puddles on the ground. This will prove fatal in sufficient quantity. Always drain the coolant into a sealable container. Coolant should be reused unless it is contaminated or several years old.

  1. Loosen the accessory drive belt and remove.
  2.  
  3. Without discharging the air conditioning system, remove the compressor and mounting bracket and stow to the side of the engine compartment.
  4.  
  5. Remove the power steering pump bracket and suspend out of the way.
  6.  
  7. Disconnect the hoses at the thermostat housing.
  8.  
  9. Remove the rocker arm cover.
  10.  
  11. Remove the rocker arms, bridges, pivots and pushrods. Keep them in the order they were removed!
  12.  



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Fig. Fig. 8: Remove the pushrods. Remember to keep them in order



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Fig. Fig. 9: Disconnect the coolant hoses from the head

  1. Remove the intake and exhaust manifolds.
  2.  
  3. Remove the head bolts.
  4.  



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Fig. Fig. 10: Remove the bolts securing the head. A breaker bar will be necessary to loosen them



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Fig. Fig. 11: Carefully lift the head from the block ...



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Fig. Fig. 12: ... then remove and discard the old gasket

  1. Lift the head off the engine and place it on a clean workbench.
  2.  
  3. Remove the head gasket.
  4.  
  5. Clean and inspect the cylinder head thoroughly. Refer to the engine reconditioning portion outlined later in this section.
  6.  

To install:
  1. Install the head gasket. Apply sealer to both sides of the new gasket; never to the head or block surfaces!
  2.  

1989-98 cylinder head gaskets used on the 2.5L are a composition gasket. The gasket is to be installed DRY. DO NOT use sealing compound.

  1. Fabricate two cylinder head alignment dowels from used head bolts. Use the longest head bolts. Cut the bolt off below the hex head. Next cut a slot in the top of the dowel to allow easier removal.
  2.  



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Fig. Fig. 13: Alignment dowel fabrication



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Fig. Fig. 14: Alignment dowel placement

  1. Install cylinder head alignment dowels. Install head gasket (manufacturer number up) and cylinder head.
  2.  

Cylinder head bolts should be reused only once. Replace head bolts which were previously used or are marked with paint. If head bolts are to be reused, mark each head with paint for later reference.



Click image to see an enlarged view

Fig. Fig. 15: 2.5L cylinder head torque sequence

  1. Install cylinder head bolts replacing alignment dowels with cylinder head bolts as you go. Coat cylinder head bolt 8 (1984-88) or bolt 7 (1989-98) with Permatex® No. 2 sealant, or equivalent, and install.
  2.  
  3. Tighten cylinder head bolts in the correct sequence, to the following torque specifications:

    On 1984-88 models, using three steps, tighten all bolts in sequence (except bolt 8) to 85 ft. lbs. (115 Nm); tighten bolt 8 to 75 ft. lbs. (101 Nm)
     
    On 1989-98 models, using three steps, tighten bolts 1 through 10 in sequence to 22 ft. lbs. (30 Nm), then tighten bolts 1 through 10 in sequence to 45 ft. lbs. (61 Nm). Check (in sequence) to verify that all of the head bolts are tightened to 45 ft. lbs. (61 Nm). Next, tighten bolts 1 through 6 in sequence to 110 ft. lbs. (150 Nm), bolt 7 to 100 ft. lbs. (136 Nm), and bolts 8 through 10 in sequence to 110 ft. lbs. (150 Nm). Check (in sequence) to verify that all of the head bolts are tightened to the correct torque.
     

  4.  
  5. If not alraedy done, clean and mark each head bolt with a dab of paint after the final tightening sequence.
  6.  

Some head bolts used on the spark plug side of the 1984 2.5L were improperly hardened and may break under the head during service or at head installation while torquing the bolts. Engines with the defective bolts are serial numbers 310U06 through 310U14. Whenever a broken bolt is found, replace all bolts on the spark plug side of the head with bolt number 400 6593.

  1. Install the rocker arm cover.
  2.  
  3. Install the intake and exhaust manifolds.
  4.  
  5. Connect the hoses at the thermostat housing.
  6.  
  7. Install power steering pump bracket and pump.
  8.  
  9. Install air conditioning compressor mounting bracket. Tighten to 30 ft. lbs. (41 Nm). Install compressor and tighten to 20 ft. lbs. (27 Nm).
  10.  
  11. Install the accessory drive belt.
  12.  

The accessory drive belt must be routed correctly. Incorrect routing can cause the water pump to turn in the opposite direction causing the engine to overheat.

  1. Check to be sure that any disconnected wiring harnesses for this procedure have been connected properly.
  2.  
  3. Fill the cooling system.
  4.  
  5. Connect the battery ground.
  6.  

2.8L Engines

See Figure 16

LEFT SIDE
  1. Disconnect the negative battery cable. Raise and support the vehicle safely. Disconnect the exhaust pipe from the exhaust manifold.
  2.  
  3. Drain the coolant from the block and lower the vehicle.
  4.  


CAUTION
When draining the coolant, keep in mind that cats and dogs are attracted by ethylene glycol antifreeze, and are quite likely to drink any that is left in an uncovered container or in puddles on the ground. This will prove fatal in sufficient quantity. Always drain the coolant into a sealable container. Coolant should be reused unless it is contaminated or several years old.

  1. Remove the intake manifold.
  2.  
  3. Remove the exhaust manifold.
  4.  
  5. If equipped, remove the power steering pump and bracket.
  6.  
  7. Remove the dipstick tube.
  8.  
  9. Loosen the rocker arm bolts and remove the pushrods. Keep the pushrods in the same order as removed.
  10.  
  11. Remove the cylinder head bolts in stages and in the reverse order of the tightening sequence.
  12.  
  13. Remove the cylinder head. Do not pry on the head to loosen.
  14.  
  15. Clean and inspect the cylinder head thoroughly. Refer to the engine reconditioning portion outlined later in this section.
  16.  

To install:
  1. Thoroughly clean the head-to-block mating surface. All bolt holes must be free of foreign material.
  2.  
  3. Place a new head gasket on the block with the words "This Side Up'' facing upward.
  4.  
  5. Position the cylinder head on the block.
  6.  
  7. Coat the cylinder head bolts with RTV silicone sealant and install them. Tighten the bolts, in sequence, in three equal stages. The final stage should be 70 ft. lbs. (95 Nm).
  8.  
  9. Install the pushrods, keeping them in the same order as removed.
  10.  
  11. Install the rocker arms.
  12.  
  13. Install the dipstick tube.
  14.  
  15. Install the power steering pump and bracket.
  16.  
  17. Install the exhaust manifold.
  18.  
  19. Install the intake manifold.
  20.  
  21. Connect the exhaust pipe from the exhaust manifold.
  22.  
  23. Fill the cooling system.
  24.  
  25. Connect the negative battery cable.
  26.  
  27. Adjust the valves.
  28.  



Click image to see an enlarged view

Fig. Fig. 16: Cylinder head torque sequence on 2.8L engines

RIGHT SIDE
  1. Disconnect the negative battery cable. Raise and support the vehicle safely. Drain the coolant from the block.
  2.  


CAUTION
When draining the coolant, keep in mind that cats and dogs are attracted by ethylene glycol antifreeze, and are quite likely to drink any that is left in an uncovered container or in puddles on the ground. This will prove fatal in sufficient quantity. Always drain the coolant into a sealable container. Coolant should be reused unless it is contaminated or several years old.

  1. Disconnect the exhaust pipe and lower the vehicle.
  2.  
  3. If equipped, remove the cruise control servo bracket.
  4.  
  5. Remove the alternator and air pump bracket assembly.
  6.  
  7. Remove the intake manifold.
  8.  
  9. Loosen the rocker arm nuts and remove the pushrods. Keep the pushrods in the order in which they were removed.
  10.  
  11. Remove the cylinder head bolts in stages and in the reverse order of the tightening sequence.
  12.  
  13. Remove the cylinder head. Do not pry on the cylinder head to loosen it.
  14.  
  15. Clean and inspect the cylinder head thoroughly. Refer to the engine reconditioning portion outlined later in this section.
  16.  

To install:
  1. Thoroughly clean the head-to-block mating surface. All bolt holes must be free of foreign material.
  2.  
  3. Place a new head gasket on the block with the words "This Side Up'' facing upward.
  4.  
  5. Position the cylinder head on the block.
  6.  
  7. Coat the cylinder head bolts with RTV silicone sealant and install them. Tighten the bolts, in sequence, in three equal stages. The final stage should be 70 ft. lbs. (95 Nm).
  8.  
  9. Install the pushrods, keeping them in the same order as removed.
  10.  
  11. Install the rocker arms.
  12.  
  13. Install the exhaust manifold.
  14.  
  15. Install the intake manifold.
  16.  
  17. Connect the exhaust pipe from the exhaust manifold.
  18.  
  19. Fill the cooling system.
  20.  
  21. Connect the negative battery cable.
  22.  
  23. Adjust the valve lash.
  24.  

4.0L Engines

See Figure 17

  1. Disconnect the negative battery cable.
  2.  
  3. Drain the cooling system.
  4.  
  5. Disconnect the hoses at the thermostat housing.
  6.  
  7. Properly relieve the fuel system pressure.
  8.  
  9. Remove the cylinder head cover.
  10.  
  11. Loosen the rocker arms.
  12.  
  13. Remove the pushrods.
  14.  

The valvetrain components must be replaced in their original positions.

  1. Remove the intake and exhaust manifold from the cylinder head.
  2.  
  3. Disconnect the spark plug wires and remove the spark plugs.
  4.  
  5. Disconnect the temperature sending unit wire, ignition coil and bracket assembly from the engine.
  6.  
  7. Remove the accessory drive belt(s).
  8.  
  9. Unbolt and set aside the power steering pump and bracket. Do not disconnect the hoses.
  10.  
  11. Remove the intake and exhaust manifold assembly.
  12.  
  13. If equipped with A/C, perform the following:
    1. Remove the compressor and position it aside with the lines attached.
    2.  
    3. Remove the compressor bracket bolts from the cylinder head.
    4.  
    5. Loosen the through bolt at the bottom of the bracket.
    6.  

  14.  
  15. Remove the alternator.
  16.  
  17. Remove the cylinder head bolts, the cylinder head and gasket from the block.
  18.  

Bolt No. 14 cannot be removed until the head is moved forward. Pull the bolt out as far as it will go and suspend in place by wrapping with tape.

  1. Discard the gasket. Thoroughly clean the head-to-block mating surface.
  2.  
  3. Clean and inspect the cylinder head thoroughly. Refer to the engine reconditioning portion outlined later in this section.
  4.  

To install:
  1. Coat a new head gasket with suitable sealing compound and place it on the block. Most replacement gaskets will have the word TOP stamped on them.
  2.  

Apply sealing compound only to the cylinder head gasket. Do not allow sealing compound to enter the cylinder bore.



Click image to see an enlarged view

Fig. Fig. 17: Cylinder head bolt torque sequence

The 1991-98 cylinder head gaskets used on the 4.0L are a composition gasket. The gasket is to be installed DRY. DO NOT use sealing compound.

  1. Install the cylinder head and bolts. The threads of bolt No. 11 must be coated with Loctite® 592 sealant before installation. Tighten the bolts in 3 steps, using the correct sequence:
    1. Tighten all bolts to 22 ft. lbs. (30 Nm).
    2.  
    3. Tighten all bolts to 45 ft. lbs. (61 Nm).
    4.  
    5. Retighten all bolts to 45 ft. lbs. (61 Nm).
    6.  
    7. Tighten bolts 1 through 10 in sequence to 110 ft. lbs. (150 Nm).
    8.  
    9. Tighten bolt 11 to 100 ft. lbs. (136 Nm)
    10.  
    11. Tighten bolts 12 through 14 to 110 ft. lbs. (150 Nm)
    12.  

  2.  

Cylinder head bolts should be reused only once. Replace the head bolts which were previously used or are marked with paint. If head bolts are to be reused, mark each head bolt with paint for future reference. Head bolts should be installed using sealer.

  1. Install the ignition coil.
  2.  
  3. Install the air conditioning compressor.
  4.  
  5. Install the alternator.
  6.  
  7. Install the intake and exhaust manifold assembly.
  8.  
  9. Install the power steering pump and bracket.
  10.  
  11. Install the accessory drive belt(s).
  12.  
  13. Connect the temperature sending unit wire, ignition coil and bracket.
  14.  
  15. Install the spark plugs and wires.
  16.  
  17. Install the pushrods, rocker arm assembly, gasket and cylinder head cover.
  18.  
  19. Connect the hoses at the thermostat housing.
  20.  
  21. Fill the cooling system.
  22.  
  23. Connect the negative battery cable.
  24.  
  25. Run the engine to normal operating temperature and check for leaks.
  26.  

5.2L and 5.9L Engines

See Figures 18, 19 and 20

  1. Disconnect the negative battery cable.
  2.  
  3. Properly relieve the fuel system pressure.
  4.  
  5. Drain the cooling system.
  6.  
  7. Remove the alternator.
  8.  
  9. Disconnect the PCV valve.
  10.  
  11. Disconnect the EVAP fuel lines.
  12.  
  13. Remove the air cleaner and disconnect the fuel lines.
  14.  
  15. Disconnect the accelerator linkage, speed control cable, if equipped, and transmission kickdown cables.
  16.  
  17. Remove the return spring.
  18.  
  19. Remove the distributor cap and wires.
  20.  
  21. Disconnect the coil wires.
  22.  
  23. Disconnect the heat indicator sending unit wire.
  24.  
  25. Disconnect the heater and bypass hoses.
  26.  
  27. Remove the cylinder head covers, discard the gaskets.
  28.  
  29. Remove the intake manifold and throttle body.
  30.  
  31. Remove the exhaust manifolds.
  32.  
  33. Remove the rocker arm assemblies and pushrods.
  34.  



Click image to see an enlarged view

Fig. Fig. 18: 5.2L and 5.9L cylinder head assembly

Identify the rocker arms and pushrods for installation purposes.

  1. Remove the spark plugs.
  2.  
  3. Remove the cylinder head bolts.
  4.  
  5. Remove the heads and discard the gaskets.
  6.  
  7. Thoroughly clean the gasket mating surfaces.
  8.  
  9. Clean and inspect the cylinder head thoroughly. Refer to the engine reconditioning portion outlined later in this section.
  10.  

To install:
  1. Apply Perfect Sealer No. 5 or equivalent, to the inner corners of the new head gaskets.
  2.  



Click image to see an enlarged view

Fig. Fig. 19: Apply sealer at the locations indicated

  1. Position the head gaskets onto the block.
  2.  
  3. Position the cylinder heads onto the cylinder block.
  4.  



Click image to see an enlarged view

Fig. Fig. 20: Cylinder head torque sequence

  1. Install the cylinder head bolts as follows:
    1. Tighten all bolts, in sequence, to 50 ft. lbs. (68 Nm).
    2.  
    3. Tighten all bolts, in sequence, to 105 ft. lbs. (143 Nm).
    4.  
    5. Repeat Step b to ensure the torque is correct.
    6.  

  2.  
  3. Install the pushrods and rocker arms to their original positions.
  4.  
  5. Install the intake and exhaust manifolds.
  6.  
  7. Install the spark plugs.
  8.  
  9. Install the coil wires.
  10.  
  11. Connect the heat indicating sending unit wire.
  12.  
  13. Connect the heater and bypass hoses.
  14.  
  15. Install the distributor cap and wires.
  16.  
  17. Hook up the return spring.
  18.  
  19. Connect the accelerator linkage, speed control cable, if equipped and transmission kickdown cables.
  20.  
  21. Install the fuel lines.
  22.  
  23. Install the alternator.
  24.  
  25. Install the intake manifold-to-alternator bracket support rod.
  26.  
  27. Place new cylinder head cover gaskets into position and install the cylinder head covers.
  28.  
  29. Install the PCV valve.
  30.  
  31. Connect the EVAP lines.
  32.  
  33. Install the air cleaner.
  34.  
  35. Fill the cooling system.
  36.  
  37. Connect the negative battery cable. Start the engine and check for leaks.
  38.  

 
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