AutoZone 1991 Plymouth Colt-Import 1.5L MFI SOHC 4cyl | Repair Guides | Engine & Engine Overhaul | Engine & Engine Overhaul | Cylinder Head | AutoZone.com

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    Ford Pick-ups and Broncos 1987-1996 Repair Guide

    Cylinder Head

    Print

    REMOVAL & INSTALLATION



    4.9L Engine

    See Figure 1



    Click image to see an enlarged view

    Fig. Fig. 1: 4.9L engine head bolt torque sequence

    1. Disconnect the negative battery cable.
    2.  
    3. Drain the cooling system.
    4.  
    5. If extra working space is desired, remove the hood.
    6.  
    7. Remove the throttle body inlet tubes.
    8.  
    9. Remove the air conditioning compressor.
    10.  
    11. Remove the condenser.
    12.  
    13. Disconnect the heater hoses from the water pump and coolant outlet housing.
    14.  
    15. Remove the radiator.
    16.  
    17. Remove the engine fan and fan drive, the water pump pulley and the drive belt.
    18.  
    19. Disconnect the accelerator cable and retracting spring.
    20.  
    21. Disconnect the power brake hose at the manifold.
    22.  
    23. Disconnect the transmission kickdown rod on trucks with automatic transmission.
    24.  
    25. Disconnect the muffler inlet pipe at the exhaust manifold. Pull the muffler inlet pipe down. Remove the gasket.
    26.  
    27. Disconnect the EEC harness from all the sensors.
    28.  
    29. Tag and disconnect all remaining wiring from the head and related components.
    30.  
    31. Remove the alternator, leaving the wires connected and position it out of the way.
    32.  
    33. Remove the air pump and bracket.
    34.  
    35. Remove the power steering pump and position it out of the way with the hoses still connected.
    36.  
    37. If the truck is equipped with an air compressor, bleed the two pressure lines and remove the compressor and bracket.
    38.  
    39. Remove the valve cover.
    40.  
    41. Loosen the rocker arm bolts so they can be pivoted out of the way. Remove the pushrods in sequence so that they can be identified and reinstalled in their original positions.
    42.  
    43. Disconnect the spark plug wires at the spark plugs.
    44.  
    45. Remove the cylinder head bolts and remove the cylinder head. Do not pry between the cylinder head and the block as the gasket surfaces maybe damaged.
    46.  

    To install:
    1. Clean the head and block gasket surfaces. If the cylinder head was removed for a gasket change, check the flatness of the cylinder head and block.
    2.  
    3. Position the gasket on the cylinder block.
    4.  
    5. Install a new gasket on the flange of the muffler inlet pipe.
    6.  
    7. Lift the cylinder head above the cylinder block and lower it into position using two head bolts installed through the head as guides.
    8.  
    9. Coat the threads of the Nos. 1 and 6 bolts for the right side of the cylinder head with a small mount of water-resistant sealer. Oil the threads of the remaining bolts. Install, but do not tighten, two bolts at the opposite ends of the head to hold the head and gasket in position.
    10.  
    11. For 1987-94 models, the cylinder head bolts are tightened in 3 progressive steps. Tighten them in the proper sequence as follows:

      Step 1: 50-55 ft. lbs. (68-75 Nm)
       
      Step 2: 60-65 ft. lbs. (81-88 Nm)
       
      Step 3: 70-85 ft. lbs. (95-115 Nm)
       

    12.  

    1. For 1995 models, tighten all bolts in numerical sequence in three steps:

      Step 1: 25-35 ft. lbs. (34-47 Nm)
       
      Step 2: 48-55 ft. lbs. (65-74 Nm)
       
      Step 3: Rotate all bolts an additional 80-100°
       

    2.  

    1. For 1996 models, tighten all bolts in numerical sequence in two steps:

      Step 1: 45-55 ft. lbs. (61-74 Nm)
       
      Step 2: Rotate all bolts an additional 80-100°
       

    2.  

    1. Apply Lubriplate® to both ends of the pushrods and install them in their original positions.
    2.  
    3. Apply Lubriplate® to both the fulcrum and seat and position the rocker arms on the valves and pushrods.
    4.  
    5. Adjust the valves, as outlined below.
    6.  
    7. Install the valve cover.
    8.  
    9. Install the air compressor and bracket.
    10.  
    11. Install the power steering pump.
    12.  
    13. Install the air pump and bracket.
    14.  
    15. Install the alternator.
    16.  
    17. Connect all wiring at the head and related components.
    18.  
    19. Connect the EEC harness to all the sensors.
    20.  
    21. Connect the muffler inlet pipe at the exhaust manifold.
    22.  
    23. Connect the transmission kickdown rod on trucks with automatic transmission.
    24.  
    25. Connect the power brake hose at the manifold.
    26.  
    27. Connect the accelerator cable and retracting spring.
    28.  
    29. Install the water pump pulley, the engine fan and fan drive and the drive belt.
    30.  
    31. Install the radiator.
    32.  
    33. Connect the fuel line at the fuel pump.
    34.  
    35. Connect the heater hoses at the water pump and coolant outlet housing.
    36.  
    37. Connect the negative battery cable.
    38.  
    39. Install the condenser.
    40.  
    41. Install the air conditioning compressor.
    42.  
    43. Install the throttle body inlet tubes.
    44.  
    45. Fill and bleed the cooling system.
    46.  
    47. Install the hood.
    48.  

    1987 5.8L Engine With 4-Bbl. Carburetor
    1. Drain the cooling system.
    2.  
    3. Remove the intake manifold and carburetor.
    4.  
    5. Remove the rocker arm cover(s).
    6.  
    7. If the right cylinder head is to be removed, loosen the alternator adjusting arm bolt and remove the alternator mounting bracket bolt and spacer. Swing the alternator down and out of the way. Remove the air cleaner inlet duct from the right cylinder head assembly.
    8.  

    If the left cylinder head is being removed, remove the bolts fastening the accelerator shaft assembly at the front of the cylinder head. On vehicles equipped with air conditioning, the system must be discharged and the compressor removed. The procedure is best left to an air conditioning specialist. Persons not familiar with air conditioning systems can be easily injured when working on the systems.

    1. Disconnect the exhaust manifold(s) from the muffler inlet pipe(s).
    2.  
    3. Loosen the rocker arm stud nuts so that the rocker arms can be rotated to the side. Remove the pushrods and identify them so that they can be reinstalled in their original positions.
    4.  
    5. Remove the cylinder head bolts and lift the cylinder head from the block.
    6.  

    To install the cylinder head(s):
    1. Clean the cylinder head, intake manifold, the valve cover and the head gasket surfaces.
    2.  
    3. A specially treated composition head gasket is used. Do not apply sealer to a composition gasket. Position the new gasket over the locating dowels on the cylinder block. Then, position the cylinder head on the block and install the attaching bolts.
    4.  
    5. The cylinder head bolts are tightened in progressive steps. Tighten all the bolts in the proper sequence to:

      Step 1: 85 ft. lbs. (115 Nm)
       
      Step 2: 95 ft. lbs. (128 Nm)
       
      Step 3: 105-112 ft. lbs. (142-151 Nm)
       

    6.  

    1. Clean the pushrods. Blow out the oil passage in the rods with compressed air. Check the pushrods for straightness by rolling them on a piece of glass. Never try to straighten a bent pushrod; always replace it.
    2.  
    3. Apply Lubriplate® to the ends of the pushrods and install them in their original positions.
    4.  
    5. Apply Lubriplate® to the rocker arms and their fulcrum seats and install the rocker arms. Adjust the valves.
    6.  
    7. Position a new gasket(s) on the muffler inlet pipe(s) as necessary. Connect the exhaust manifold(s) at the muffler inlet pipe(s).
    8.  
    9. If the right cylinder head was removed, install the alternator, ignition coil and air cleaner duct on the right cylinder head. Adjust the drive belt.
    10.  
    11. If the left cylinder head was removed, install the accelerator shaft assembly at the front of the cylinder head.
    12.  
    13. Clean the valve cover and the cylinder head gasket surfaces. Place the new gaskets in the covers, making sure that the tabs of the gasket engage the notches provided in the cover. Install the compressor, evaluate, charge and leak test the system. Let an air conditioning specialist do this.
    14.  
    15. Install the intake manifold and related parts.
    16.  
    17. Fill and bleed the cooling system.
    18.  

    5.0L and 5.8L Fuel Injected Engines

    See Figures 2, 3, 4, 5 and 6



    Click image to see an enlarged view

    Fig. Fig. 2: Use a long breaker bar to ease removal of the cylinder head bolts-5.0L engine shown



    Click image to see an enlarged view

    Fig. Fig. 3: Lift off the cylinder head from the block and set in a safe location



    Click image to see an enlarged view

    Fig. Fig. 4: Stuff rags in the open cylinders before scraping mating surfaces completely clean



    Click image to see an enlarged view

    Fig. Fig. 5: Use a torque wrench to tighten the cylinder head bolts to the proper torque specification



    Click image to see an enlarged view

    Fig. Fig. 6: Cylinder head bolt tightening sequence-all V8 gasoline engines

    1. Drain the cooling system.
    2.  
    3. Remove the intake manifold and EFI throttle body.
    4.  
    5. Remove the rocker arm cover(s).
    6.  
    7. If the right cylinder head is to be removed, lift the tensioner and remove the drive belt. Loosen the alternator adjusting arm bolt and remove the alternator mounting bracket bolt and spacer. Swing the alternator down and out of the way. Remove the air cleaner inlet duct.
    8.  

    If the left cylinder head is being removed, remove the air conditioning compressor ( Routine Maintenance ). Persons not familiar with air conditioning systems should exercise extreme caution, perhaps leaving this job to a professional. Remove the oil dipstick and tube. Remove the cruise control bracket.

    1. Disconnect the exhaust manifold(s) from the muffler inlet pipe(s).
    2.  
    3. Loosen the rocker arm stud nuts so that the rocker arms can be rotated to the side. Remove the pushrods and identify them so that they can be reinstalled in their original positions.
    4.  
    5. Disconnect the Thermactor® air supply hoses at the check valves. Cover the check valve openings.
    6.  
    7. Remove the cylinder head bolts and lift the cylinder head from the block. Remove the discard the gasket.
    8.  

    To install the cylinder head(s):
    1. Clean the cylinder head, intake manifold, the valve cover and the head gasket surfaces.
    2.  
    3. A specially treated composition head gasket is used. Do not apply sealer to a composition gasket. Position the new gasket over the locating dowels on the cylinder block. Then, position the cylinder head on the block and install the attaching bolts.
    4.  
    5. For 1987-91 models, the cylinder head bolts are tightened in progressive steps. Tighten all the bolts in the proper sequence to:
    6.  

    5.0L Engines



    Step 1: 55-65 ft. lbs. (75-88 Nm)
     
    Step 2: 66-72 ft. lbs. (89-97 Nm)
     

    5.8L Engines


    Step 1: 85 ft. lbs. (115 Nm)
     
    Step 2: 95 ft. lbs. (129 Nm)
     
    Step 3: 105-112 ft. lbs. (142-151 Nm)
     

    All 1995-96 5.0L engines came with the flanged type of bolt only.

    1. For 1992-96 models, the cylinder head bolts are tightened in progressive steps. Tighten all the bolts in the proper sequence to:
    2.  

    5.0L engines with FLANGED head bolts


    Step 1: 25-35 ft. lbs. (34-47 Nm)
     
    Step 2: 45-55 ft. lbs. (61-75 Nm)
     
    Step 3: Rotate all bolts an additional 85-95°
     

    5.0L engines with HEX head bolts


    Step 1: 55-65 ft. lbs. (75-88 Nm)
     
    Step 2: 65-72 ft. lbs. (88-98 Nm)
     

    5.8L engines


    Step 1: 95-105 ft. lbs. (129-142 Nm)
     
    Step 3: 105-112 ft. lbs. (142-151 Nm)
     

    1. Clean the pushrods. Blow out the oil passage in the rods with compressed air. Check the pushrods for straightness by rolling them on a piece of glass. Never try to straighten a bent pushrod; always replace it.
    2.  
    3. Apply Lubriplate® to the ends of the pushrods and install them in their original positions.
    4.  
    5. Apply Lubriplate® to the rocker arms and their fulcrum seats and install the rocker arms. Adjust the valves.
    6.  
    7. Position a new gasket(s) on the muffler inlet pipe(s) as necessary. Connect the exhaust manifold(s) at the muffler inlet pipe(s).
    8.  
    9. If the right cylinder head was removed, install the alternator and air cleaner duct. Install the drive belt.
    10.  
    11. If the left cylinder head was removed, install the compressor (see Routine Maintenance ). Install the dipstick and cruise control bracket.
    12.  
    13. Clean the valve cover and the cylinder head gasket surfaces. Place the new gaskets in the covers, making sure that the tabs of the gasket engage the notches provided in the cover. Evacuate, charge and leak test the air conditioning system (see Routine Maintenance ).
    14.  
    15. Install the intake manifold and related parts. Install the Thermactor® hoses.
    16.  
    17. Fill and bleed the cooling system.
    18.  

    7.5L Engine With 4-Bbl. Carburetor
    1. Drain the cooling system.
    2.  
    3. Remove the intake manifold and carburetor as an assembly.
    4.  
    5. Disconnect the exhaust pipe from the exhaust manifold.
    6.  
    7. Loosen the air conditioning compressor drive belt, if so equipped.
    8.  
    9. Loosen the alternator attaching bolts and remove the bolt attaching the alternator bracket to the right cylinder head.
    10.  
    11. Disconnect the air conditioning compressor from the engine and move it aside, out of the way. Do not discharge the air conditioning system.
    12.  
    13. Remove the bolts securing the power steering reservoir bracket to the left cylinder head. Position the reservoir and bracket out of the way.
    14.  
    15. Remove the valve covers. Remove the rocker arm bolts, rocker arms, oil deflectors, fulcrums and pushrods in sequence so that they can be reinstalled in their original positions.
    16.  
    17. Remove the cylinder head bolts and lift the head and exhaust manifold off the engine. If necessary, pry at the forward corners of the cylinder head against the casting bosses provided on the cylinder block. Do not damage the gasket mating surfaces of the cylinder head and block by prying against them.
    18.  
    19. Remove all gasket material from the cylinder head and block. Clean all gasket material from the mating surfaces of the intake manifold. If the exhaust manifold was removed, clean the mating surfaces of the cylinder head and exhaust manifold. Apply a thin coat of graphite grease to the cylinder head exhaust port areas and install the exhaust manifold.
    20.  
    21. Position two long cylinder head bolts in the two rear lower bolt holes of the left cylinder head. Place a long cylinder head bolt in the rear lower bolt hole of the right cylinder head. Use rubber bands to keep the bolts in position until the cylinder heads are installed on the cylinder block.
    22.  
    23. Position new cylinder head gaskets on the cylinder block dowels. Do not apply sealer to the gaskets, heads, or block.
    24.  
    25. Place the cylinder heads on the block, guiding the exhaust manifold studs into the exhaust pipe connections. Install the remaining cylinder head bolts. The longer bolts go in the lower row of holes.
    26.  
    27. Tighten all the cylinder head attaching bolts in the proper sequence in three stages: 75 ft. lbs. (102 Nm), 105 ft. lbs. (142 (Nm) and finally to 135 ft. lbs. (183 Nm). When this procedure is used, it is not necessary to retighten the heads after extended use.
    28.  
    29. Make sure that the oil holes in the pushrods are open and install the pushrods in their original positions. Place a dab of Lubriplate® to the ends of the pushrods before installing them.
    30.  
    31. Lubricate and install the valve rockers. Make sure that the pushrods remain seated in their lifters.
    32.  
    33. Connect the exhaust pipes to the exhaust manifolds.
    34.  
    35. Install the intake manifold and carburetor assembly. Tighten the intake manifold attaching bolts in the proper sequence to 25-30 ft. lbs. (34-41 Nm)
    36.  
    37. Install the air conditioning compressor to the engine.
    38.  
    39. Install the power steering reservoir to the engine.
    40.  
    41. Apply oil-resistant sealer to one side of the new valve cover gaskets and lay the cemented side in place in the valve cover. Install the covers.
    42.  
    43. Install the alternator to the right cylinder head. If applicable, adjust the alternator drive belt tension.
    44.  
    45. Adjust the air conditioning compressor drive belt tension.
    46.  
    47. Fill the radiator with coolant.
    48.  
    49. Start the engine and check for leaks.
    50.  

    Fuel Injected 7.5L Engine
    1. Drain the cooling system.
    2.  
    3. Remove the upper and lower intake manifolds (see above and Fuel System .
    4.  
    5. Disconnect the exhaust pipe from the exhaust manifold.
    6.  
    7. Loosen the air conditioning compressor drive belt, if so equipped.
    8.  
    9. Loosen the alternator attaching bolts and remove the bolt attaching the alternator bracket to the right cylinder head.
    10.  
    11. Disconnect the air conditioning compressor from the engine and move it aside, out of the way. Do not discharge the air conditioning system.
    12.  
    13. Remove the bolts securing the power steering reservoir bracket to the left cylinder head. Position the reservoir and bracket out of the way. On motor home chassis, remove the oil filler tube.
    14.  
    15. Remove the valve covers. Remove the rocker arm bolts, rocker arms, oil deflectors, fulcrums and pushrods in sequence so that they can be reinstalled in their original positions.
    16.  
    17. Remove the cylinder head bolts and lift the head and exhaust manifold off the engine. If necessary, pry at the forward corners of the cylinder head against the casting bosses provided on the cylinder block. Do not damage the gasket mating surfaces of the cylinder head and block by prying against them.
    18.  
    19. Remove all gasket material from the cylinder head and block. Clean all gasket material from the mating surfaces of the intake manifold. If the exhaust manifold was removed, clean the mating surfaces of the cylinder head and exhaust manifold. Apply a thin coat of graphite grease to the cylinder head exhaust port areas and install the exhaust manifold.
    20.  
    21. Position two long cylinder head bolts in the two rear lower bolt holes of the left cylinder head. Place a long cylinder head bolt in the rear lower bolt hole of the right cylinder head. Use rubber bands to keep the bolts in position until the cylinder heads are installed on the cylinder block.
    22.  
    23. Position new cylinder head gaskets on the cylinder block dowels. Do not apply sealer to the gaskets, heads, or block.
    24.  
    25. Place the cylinder heads on the block, guiding the exhaust manifold studs into the exhaust pipe connections. Install the remaining cylinder head bolts. The longer bolts go in the lower row of holes.
    26.  
    27. Tighten all the cylinder head attaching bolts in the proper sequence in three stages: 80-90 ft. lbs. (108-122 Nm), 100-110 ft.lbs. (135-149 Nm) and finally to 130-140 ft. lbs. (176-190 Nm). When this procedure is used, it is not necessary to retighten the heads after extended use.
    28.  
    29. Make sure that the oil holes in the pushrods are open and install the pushrods in their original positions. Place a dab of Lubriplate® to the ends of the pushrods before installing them.
    30.  
    31. Lubricate and install the valve rockers. Make sure that the pushrods remain seated in their lifters.
    32.  
    33. Connect the exhaust pipes to the exhaust manifolds.
    34.  
    35. Install the upper and lower intake manifolds.
    36.  
    37. Install the air conditioning compressor.
    38.  
    39. Install the power steering reservoir.
    40.  
    41. Apply oil-resistant sealer to one side of the new valve cover gaskets and lay the cemented side in place in the valve cover. Install the covers.
    42.  
    43. Install the alternator. If applicable, adjust the drive belt.
    44.  
    45. Adjust the air conditioning compressor drive belt tension.
    46.  
    47. On motor home chassis, install the oil filler tube.
    48.  
    49. Fill and bleed the cooling system.
    50.  
    51. Start the engine and check for leaks.
    52.  

    1987-93 6.9L and/or 7.3L Diesel Engines

    See Figures 7, 8 and 9



    Click image to see an enlarged view

    Fig. Fig. 7: Diesel fuel hose and engine ground harness connections



    Click image to see an enlarged view

    Fig. Fig. 8: 7.3L diesel engine head bolt torque sequence



    Click image to see an enlarged view

    Fig. Fig. 9: 6.9L diesel engine cylinder head bolt tightening sequence

    1. Disconnect both negative battery cables.
    2.  
    3. Drain the cooling system and remove the radiator fan shroud halves.
    4.  
    5. Remove the radiator fan and clutch assembly using special tool T83T-6312-A and B, or equivalent.
    6.  

    This tool (T83T-6312-A and B) is available through Ford Dealers and through many tool rental shops.

    The fan clutch uses a left-hand thread and must be removed by turning the nut CLOCKWISE.

    1. Label and disconnect the wiring from the alternator.
    2.  
    3. Remove the adjusting bolts and pivot bolts from the alternator and the vacuum pump and remove both units.
    4.  
    5. Remove the alternator and vacuum pump.
    6.  
    7. Remove the heater hose from the cylinder head.
    8.  
    9. Remove the fuel injection pump as described in Chapter 5 under Diesel Fuel System.
    10.  
    11. Remove the intake manifold and valley cover.
    12.  
    13. Jack up the truck and safely support it with jackstands.
    14.  
    15. Disconnect the exhaust pipes from the exhaust manifolds.
    16.  
    17. Remove the clamp holding the engine oil dipstick tube in place and the bolt attaching the transmission oil dipstick to the cylinder head.
    18.  
    19. Lower the truck.
    20.  
    21. Remove the engine oil dipstick tube.
    22.  
    23. Remove the valve covers, rocker arms and pushrods. Keep the pushrods in order so they can be returned to their original positions.
    24.  
    25. Remove the nozzles and glow plugs as described in Chapter 5 under Diesel Fuel System.
    26.  
    27. Remove the cylinder head bolts and attach lifting eyes, using special tool T70P-6000 or equivalent, to each end of the cylinder heads.
    28.  
    29. Carefully lift the cylinder heads out of the engine compartment and remove the head gaskets.
    30.  

    The cylinder head pre-chambers may fall out of the heads upon removal.

    To install:
    1. Position the cylinder head gasket on the engine block and carefully lower the cylinder head in place.
    2.  

    Use care in installing the cylinder heads to prevent the pre-chambers from falling out into the cylinder bores.

    1. Install the cylinder head bolt and torque in 4 steps using the sequence shown in the illustration.
    2.  

    Lubricate the threads and the mating surfaces of the bolt heads and washers with engine oil.

    1. Dip the pushrod ends in clean engine oil and install the pushrods with the copper colored ends toward the rocker arms, making sure the pushrods are fully seated in the tappet pushrod seats.
    2.  
    3. Install the rocker arms and posts in their original positions. Apply Lubriplate® grease to the valve stem tips. Turn the engine over by hand until the timing mark is at the 11 o'clock position as viewed from the front. Install the rocker arm posts, bolts and tighten to 27 ft. lbs. (37 Nm). Install the valve covers.
    4.  
    5. Install the valley pan and the intake manifold.
    6.  
    7. Install the fuel injection pump as described in Chapter 5 under Diesel Fuel System.
    8.  
    9. Connect the heater hose to the cylinder head.
    10.  
    11. Install the fuel filter, alternator, vacuum pump and their drive belt(s).
    12.  
    13. Install the engine oil and transmission dip stick.
    14.  
    15. Connect the exhaust pipe to the exhaust manifolds.
    16.  
    17. Reconnect the alternator wiring harness and replace the air cleaner. Connect both negative battery cables.
    18.  
    19. Refill and bleed the cooling system.
    20.  
    21. Run the engine and check for fuel, coolant and exhaust leaks.
    22.  

    If necessary, purge the high pressure fuel lines of air by loosening the connector one half to one turn and cranking the engine until a solid stream of fuel, free from any bubbles, flows from the connections.

    1. Check the injection pump timing. Refer to Chapter 5 for these procedures.
    2.  
    3. Install the radiator fan and clutch assembly using special tools T83T-6312A and B or equivalent.
    4.  

    The fan clutch uses a left-hand thread. Tighten by turning the nut COUNTERCLOCKWISE. Install the radiator fan shroud halves.

    1994-96 7.3L DI Turbo Diesel Engine
    RIGHT CYLINDER HEAD

    See Figures 10, 11, 12, 13, 14, 15 and 16



    Click image to see an enlarged view

    Fig. Fig. 10: Remove the oil rail drain plug as shown-7.3L DI turbo diesel engine



    Click image to see an enlarged view

    Fig. Fig. 11: Remove the injector using special tools as shown-7.3L DI turbo diesel engine



    Click image to see an enlarged view

    Fig. Fig. 12: Special fuel injector protection sleeve and holding rack-7.3L DI turbo diesel engine



    Click image to see an enlarged view

    Fig. Fig. 13: Install a lifting eye as shown



    Click image to see an enlarged view

    Fig. Fig. 14: Use a suitable bore brush to clean out the injector bores



    Click image to see an enlarged view

    Fig. Fig. 15: Cylinder head bolt tightening sequence-7.3L DI turbo diesel engine



    Click image to see an enlarged view

    Fig. Fig. 16: Install the injectors using the special tool as shown-7.3L DI turbo diesel engine

    1. Disconnect both negative battery cables.
    2.  
    3. Drain the cooling system.
    4.  
    5. Remove the radiator.
    6.  
    7. Remove the turbocharger assembly.
    8.  
    9. Disconnect the fuel lines by disconnecting them from the rear of both cylinder heads and the fuel pump.
    10.  
    11. Label and disconnect the wiring from the alternator.
    12.  
    13. Remove the adjusting bolts and pivot bolts from the alternator and the vacuum pump and remove both units.
    14.  
    15. Remove the alternator and its bracket.
    16.  
    17. Remove the engine oil dipstick tube.
    18.  
    19. Remove the MAP sensor and position it aside.
    20.  
    21. Remove the valve cover
    22.  
    23. Remove the connectors from the injectors and glow plugs.
    24.  
    25. Remove the valve cover gasket.
    26.  
    27. Remove the high pressure oil pump supply line to the right cylinder head.
    28.  
    29. Remove the exhaust back pressure line.
    30.  
    31. Remove the three glow plug relay bracket nuts and the ground wire.
    32.  
    33. Disconnect the heater hose from the cylinder head.
    34.  
    35. Remove the outer half of the heater distribution box.
    36.  
    37. Remove the four outboard fuel injector hold-down bolts, retaining screws and four oil deflectors.
    38.  


    WARNING
    Remove the oil drain plugs prior to removing the injectors or oil could enter the combustion chamber which could result in hydrostatic lock and severe engine damage.

    1. Remove the oil rail drain plugs.
    2.  
    3. Remove the fuel injectors using Injector Remover No. T94T-9000-AH1, or equivalent. Position the tool's fulcrum beneath the fuel injector hold-down plate and over the edge of the cylinder head. Install the remover screw in the threaded hole of the fuel injector plate (see illustration). Tighten the screw to lift out the injector from its bore. Place the injector in a suitable protective sleeve such as Rotunda Injector Protective Sleeve, No. 014-00933-2, and set the injector in a suitable holding rack.
    4.  
    5. Use a suitable vacuum tool, such as Rotunda Vacuum Pump, No. 021-00037, or equivalent to remove the oil and fuel left over in the injector bores.
    6.  
    7. Remove the rocker arms and pushrods, KEEP EVERYTHING IN ORDER.
    8.  
    9. Remove the four glow plugs.
    10.  
    11. Remove the right turbo exhaust inlet pipe.
    12.  
    13. Remove the ground strap from the rear of the cylinder head.
    14.  
    15. Disconnect the fuel return line at the front of the cylinder head.
    16.  
    17. Remove the four inboard fuel injector shoulder bolts.
    18.  
    19. Remove the cylinder head bolts and attach a Rotunda Cylinder Head Lifting Bracket, 014-00932-2, or equivalent.
    20.  
    21. Carefully lift the cylinder head out of the engine compartment and remove the head gaskets.
    22.  

    To install:

    To prepare a good seat for the fuel injector O-rings, use a suitable injector sleeve brush to clean any debris from the bore.

    1. Carefully clean the cylinder block and head mating surfaces.
    2.  
    3. Position the cylinder head gasket on the engine block and carefully lower the cylinder head in place.
    4.  
    5. Install the cylinder head bolt and torque in 3 steps using the sequence shown in the illustration.
    6.  

    Lubricate the threads and the mating surfaces of the bolt heads and washers with engine oil.

    1. Connect the fuel return line to the cylinder head.
    2.  
    3. Install the four inboard injector shoulder bolts. Tighten them to 9 ft. lbs. (12 Nm).
    4.  
    5. Install the fuel injectors using special tools as follows:
      1. Lubricate the injectors with clean engine oil. Using new copper washers, carefully push the injectors square into the bore using hand pressure only to seat the O-rings.
      2.  
      3. Position the open end of Injector Replacer, No. T94T-9000-AH2, or equivalent between the fuel injector body and injector hold-down plate, while positioning the opposite end of the tool over the edge of the cylinder head.
      4.  
      5. Align the hole in the tool with the threaded hole in the cylinder head and install the bolt from the tool kit. Tighten the bolt to fully seat the injector, then remove the bolt and tool.
      6.  

    6.  
    7. Install the four outboard fuel injector hold-down bolts, the four oil deflectors and retaining screws. Tighten them to 9 ft. lbs. (12 Nm).
    8.  
    9. Dip the pushrod ends in clean engine oil and install the pushrods with the copper colored ends toward the rocker arms, making sure the pushrods are fully seated in the tappet pushrod seats.
    10.  
    11. Install the rocker arms and posts in their original positions. Apply Lubriplate® grease to the valve stem tips. Turn the engine over by hand until the timing mark is at the 11 o'clock position as viewed from the front. Install the rocker arm posts, bolts and tighten to 27 ft. lbs. (37 Nm). Install the valve covers.
    12.  
    13. Install the fuel rail drain plugs, tightening them to 8 ft. lbs. (11 Nm).
    14.  
    15. Install the oil rail drain plugs, tightening them to 53 inch lbs. (6 Nm).
    16.  
    17. Install the heater distribution box.
    18.  
    19. Install the heater hose to the cylinder head.
    20.  
    21. Install the glow plug relay bracket and ground wire.
    22.  
    23. Install the exhaust back pressure line.
    24.  
    25. Install the oil supply line to the cylinder head, tightening it to 19 ft. lbs. (26 Nm).
    26.  
    27. Install the dipstick tube.
    28.  
    29. Install the MAP sensor and screws.
    30.  
    31. Install the valve cover gasket.
    32.  
    33. Connect the wiring to the fuel injectors and glow plugs.
    34.  
    35. Install the valve cover, tightening the bolts to 8 ft. lbs. (11 Nm).
    36.  
    37. Connect the injector wiring harness to the valve cover gasket.
    38.  
    39. Install the alternator, tightening the bracket bolts to 40-55 ft. lbs. (54-75 Nm).
    40.  
    41. Connect the alternator wiring and install the drive belt.
    42.  
    43. The remainder of the installation is the reverse of the removal. Tighten the fuel pump-to-fuel line banjo bolt to 40 ft. lbs. (54 Nm).
    44.  
    45. Connect both negative battery cables.
    46.  
    47. Refill and bleed the cooling system.
    48.  
    49. Run the engine and check for fuel, coolant and exhaust leaks.
    50.  

    LEFT CYLINDER HEAD
    1. Disconnect both negative battery cables.
    2.  
    3. Drain the cooling system.
    4.  
    5. Remove the radiator.
    6.  
    7. Remove the turbocharger assembly.
    8.  
    9. Remove the two crankcase breather screws and the breather.
    10.  
    11. Disconnect the wiring from the air conditioning compressor.
    12.  
    13. Remove the four left accessory bracket bolts.
    14.  
    15. Disconnect the vacuum hose at the brake vacuum pump.
    16.  
    17. Disconnect the A/C lines from the compressor.
    18.  
    19. Remove the power steering lines from the pump.
    20.  
    21. Remove the left accessor bracket and accessories as an assembly.
    22.  
    23. Remove the valve cover
    24.  
    25. Disconnect the fuel line assembly between the cylinder heads and fuel pump.
    26.  
    27. Remove the fuel line nut from the intake manifold stud.
    28.  
    29. Disconnect the fuel return line from the cylinder head.
    30.  
    31. Remove the high pressure oil pump supply line from the cylinder head.
    32.  
    33. Raise the vehicle and support it safely on jackstands.
    34.  
    35. Remove the left turbo exhaust pipe from the manifold.
    36.  
    37. Lower the vehicle.
    38.  
    39. Remove the oil rail drain plugs.
    40.  
    41. Remove the four outboard fuel injector hold-down bolts, retaining screws and four oil deflectors.
    42.  


    WARNING
    Remove the oil drain plugs prior to removing the injectors or oil could enter the combustion chamber which could result in hydrostatic lock and severe engine damage.

    1. Remove the oil rail drain plugs.
    2.  
    3. Remove the fuel injectors using Injector Remover No. T94T-9000-AH1, or equivalent. Position the tool's fulcrum beneath the fuel injector hold-down plate and over the edge of the cylinder head. Install the remover screw in the threaded hole of the fuel injector plate (see illustration). Tighten the screw to lift out the injector from its bore. Place the injector in a suitable protective sleeve such as Rotunda Injector Protective Sleeve, No. 014-00933-2, and set the injector in a suitable holding rack.
    4.  
    5. Use a suitable vacuum tool, such as Rotunda Vacuum Pump, No. 021-00037, or equivalent to remove the oil and fuel left over in the injector bores.
    6.  
    7. Remove the rocker arms and pushrods, KEEP EVERYTHING IN ORDER.
    8.  
    9. Remove the four glow plugs.
    10.  
    11. Remove the left turbo exhaust inlet pipe.
    12.  
    13. Remove the main engine harness connectors in the left fender well and position the harness aside.
    14.  
    15. Remove the four inboard fuel injector shoulder bolts.
    16.  
    17. Remove the cylinder head bolts and attach a Rotunda Cylinder Head Lifting Bracket, 014-00932-2, or equivalent.
    18.  
    19. Carefully lift the cylinder head out of the engine compartment and remove the head gaskets.
    20.  

    To install:

    To prepare a good seat for the fuel injector O-rings, use a suitable injector sleeve brush to clean any debris from the bore.

    1. Carefully clean the cylinder block and head mating surfaces.
    2.  
    3. Position the cylinder head gasket on the engine block and carefully lower the cylinder head in place.
    4.  
    5. Install the cylinder head bolt and torque in 3 steps using the sequence shown in the illustration.
    6.  

    Lubricate the threads and the mating surfaces of the bolt heads and washers with engine oil.

    1. Apply anti-seize paste and install the glow plugs, tightening them to 14 ft. lbs. (19 Nm).
    2.  
    3. Install the four outboard fuel injector hold-down bolts, the four oil deflectors and retaining screws. Tighten them to 9 ft. lbs. (12 Nm).
    4.  
    5. Dip the pushrod ends in clean engine oil and install the pushrods with the copper colored ends toward the rocker arms, making sure the pushrods are fully seated in the tappet pushrod seats.
    6.  
    7. Install the rocker arms and posts in their original positions. Apply Lubriplate® grease to the valve stem tips. Turn the engine over by hand until the timing mark is at the 11 o'clock position as viewed from the front. Install the rocker arm posts, bolts and tighten to 27 ft. lbs. (37 Nm). Install the valve covers.
    8.  
    9. Install the four inboard injector shoulder bolts. Tighten them to 9 ft. lbs. (12 Nm).
    10.  
    11. Install the fuel injectors using special tools as follows:
      1. Lubricate the injectors with clean engine oil. Using new copper washers, carefully push the injectors square into the bore using hand pressure only to seat the O-rings.
      2.  
      3. Position the open end of Injector Replacer, No. T94T-9000-AH2, or equivalent between the fuel injector body and injector hold-down plate, while positioning the opposite end of the tool over the edge of the cylinder head.
      4.  
      5. Align the hole in the tool with the threaded hole in the cylinder head and install the bolt from the tool kit. Tighten the bolt to fully seat the injector, then remove the bolt and tool.
      6.  

    12.  
    13. Install the fuel rail drain plugs, tightening them to 8 ft. lbs. (11 Nm).
    14.  
    15. Install the oil rail drain plugs, tightening them to 53 inch lbs. (6 Nm).
    16.  
    17. Install the heater distribution box.
    18.  
    19. Install the valve cover gasket.
    20.  
    21. Connect the wiring to the fuel injectors and glow plugs.
    22.  
    23. Install the valve cover, tightening the bolts to 8 ft. lbs. (11 Nm).
    24.  
    25. Connect the engine wiring harness.
    26.  
    27. Raise and safely support the vehicle on jackstands.
    28.  
    29. Loosely install the turbo exhaust pipe to the manifold.
    30.  
    31. Lower the vehicle.
    32.  
    33. The remainder of the installation is the reverse of the removal. Tighten the fuel pump-to-fuel line banjo bolt to 40 ft. lbs. (54 Nm).
    34.  
    35. Connect both negative battery cables.
    36.  
    37. Refill and bleed the cooling system.
    38.  
    39. Run the engine and check for fuel, coolant and exhaust leaks.
    40.  

    CLEANING AND INSPECTION



    See Figures 17, 18, 19, 20, 21 and 22



    Click image to see an enlarged view

    Fig. Fig. 17: Remove combustion chamber carbon from the cylinder head with a wire brush and electric drill. Make sure all carbon is removed and not just burnished



    Click image to see an enlarged view

    Fig. Fig. 18: Check the cylinder head for warpage



    Click image to see an enlarged view

    Fig. Fig. 19: Use a gasket scraper to remove the bulk of the old head gasket from the mating surface



    Click image to see an enlarged view

    Fig. Fig. 20: An electric drill equipped with a wire wheel will expedite complete gasket removal



    Click image to see an enlarged view

    Fig. Fig. 21: Check the cylinder head for warpage along the center using a straightedge and a feeler gauge



    Click image to see an enlarged view

    Fig. Fig. 22: Be sure to check for warpage across the cylinder head at both diagonals

    1. With the valves installed to protect the valve seats, remove deposits from the combustion chambers and valve heads with a scraper and a wire brush. Be careful not to damage the cylinder head gasket surface. After the valves are removed, clean the valve guide bores with a valve guide cleaning tool. Using cleaning solvent to remove dirt, grease and other deposits, clean all bolts holes; be sure the oil passage is clean (V8 engines).
    2.  
    3. Remove all deposits from the valves with a fine wire brush or buffing wheel.
    4.  
    5. Inspect the cylinder heads for cracks or excessively burned areas in the exhaust outlet ports.
    6.  
    7. Check the cylinder head for cracks and inspect the gasket surface for burrs and nicks. Replace the head if it is cracked.
    8.  
    9. On cylinder heads that incorporate valve seat inserts, check the inserts for excessive wear, cracks, or looseness.
    10.  

    RESURFACING



    Cylinder Head Flatness

    When the cylinder head is removed, check the flatness of the cylinder head gasket surfaces.

    1. Place a straightedge across the gasket surface of the cylinder head. Using feeler gauges, determine the clearance at the center of the straightedge.
    2.  
    3. If warpage exceeds 0.003 in. (0.076mm) in a 6 in. (152mm) span, or 0.006 in. (0.152mm) over the total length, the cylinder head must be resurfaced.
    4.  
    5. If necessary to refinish the cylinder head gasket surface, do not plane or grind off more than 0.254mm (0.010 in.) from the original gasket surface.
    6.  

    When milling the cylinder heads of V8 engines, the intake manifold mounting position is altered and must be corrected by milling the manifold flange a proportionate amount. Consult an experienced machinist about this.

     
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