GM Century/Lumina/Grand Prix/Intrigue 1997-2000

Timing Chain Front Cover and Seal

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REMOVAL & INSTALLATION



3.1L and 3.4L (VIN E) Engines

WARNING
The timing chain front cover (also called the engine front cover) is made of aluminum. Use care when working with light alloy parts.


NOTE
The crankshaft front oil seal can be replaced without removing the timing chain front cover.

  1. Disconnect the negative battery cable.
  2.  
  3. Drain the engine coolant and engine oil into suitable containers.
  4.  
  5. Remove the crankshaft balancer using the procedures found in this section.
  6.  
  7. Remove the drive belt tensioner.
  8.  
  9. Without disconnecting the fluid lines, remove the power steering pump and set aside.
  10.  
  11. Remove the thermostat pipe from the front engine cover.
  12.  
  13. Remove the lower radiator hose from the water pump.
  14.  
  15. Remove the drive belt shield and remove the water pump pulley.
  16.  
  17. Remove the crankshaft position sensor from the engine timing chain front cover.
  18.  
  19. Remove the front cover bolts. Note that they are different lengths. Use care to note the position of the bolts at removal so they can be returned to their original locations. Separate the engine timing chain front cover from the engine. Discard the gasket. If the cover if being replaced with a new one, transfer the water pump to the replacement cover.
  20.  



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Fig. Timing chain front cover-3.1 and 3.4L (VIN E) engines



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Fig. Timing chain cover gasket and seal arrangement-3.1L and 3.4L (VIN E) engines

To install:

  1. Clean all parts well, especially the gasket sealing surfaces. Inspect the water pump shaft and vanes for looseness. Inspect the front cover seal for damage. If the front seal is to be replaced, use the following procedure.
    1. Note that the crankshaft front oil seal can be replaced without removing the timing chain front cover.
    2.  
    3. With the front cover on or off the engine, after removing the crankshaft balancer, pry the seal out with an appropriate prying tool.
    4.  
    5. Inspect the crankshaft, the balancer and the front cover for scratches. Replace or repair as necessary.
    6.  
    7. Lubricate the replacement crankshaft seal with clean engine oil to make installation easier.
    8.  
    9. A seal driver is recommended. Install the seal making sure the seal lip faces the engine. Tap into place with a seal driver. Support the aluminum cover underneath to prevent distortion and do not hammer on the seal. Tap in lightly until it seats.
    10.  

  2.  
  3. Coat both sides of the lower tabs of the new cover gasket for about 1 / 4 inch with sealer, GM #1052080, or equivalent. Install the gasket to the engine block taking care to align the gasket with the dowel pins in the block.
  4.  
  5. Install the front timing chain cover. Install the bolts into their original locations, as noted at removal. Tighten the large bolts to 35 ft. lbs. (47 Nm) and the small bolts to 15 ft. lbs. (21 Nm).
  6.  
  7. Install the crankshaft position sensor to the engine timing chain front cover.
  8.  
  9. Install the remainder of the components in the order in which they were removed.
  10.  
  11. Refill the engine with coolant and engine oil. A filter change is recommended.
  12.  
  13. Connect the negative battery cable.
  14.  

3.4L (VIN X) Engine

NOTE
This is a long process and requires the removal of the engine timing belt as well as the alternator. The alternator removal procedure calls for lowering the sub-frame, requiring special lifting and jacking equipment. Special tools are required. Please review the timing belt removal procedure, found in this section, before attempting to service the engine front cover (also called the Cam Interdrive Shaft Chain and Sprocket Cover). This is not a job for the inexperienced or ill-equipped.

  1. Remove the camshaft timing belt and tensioner actuator using the procedures found in this section.
  2.  
  3. Remove the camshaft timing belt idler pulleys.
  4.  
  5. Remove the engine lift bracket.
  6.  
  7. Remove both cooling fans.
  8.  
  9. Drain the cooling system into a suitable container and remove the coolant hoses from the water pump.
  10.  
  11. Remove the heater pipe retaining screws from the frame.
  12.  
  13. Remove the starter motor. Please see .
  14.  
  15. Remove the crankshaft balancer using the procedures found in this section.
  16.  
  17. Remove the alternator and set aside.
  18.  
  19. Remove the oil filter and the oil cooler from the engine.
  20.  
  21. Remove the oil pan front retaining nuts and bolts, and loosen the remainder of the oil pan bolts.
  22.  
  23. Without disconnecting the refrigerant lines, remove the air conditioning compressor and set aside.
  24.  
  25. Remove the front cover bolts. Please note that different length bolts are used. Some technicians will trace the bolt pattern of the front cover onto a piece of cardboard, using the replacement gasket as a template. As the bolts are removed, they can be poked through the cardboard in the appropriate places for assembly.
  26.  
  27. Install a device to lock the flywheel in place. GM recommends their J 37096 Flywheel Holder. Use care if using substitutes.
  28.  
  29. Lower the vehicle.
  30.  
  31. Remove the intermediate shaft belt sprocket.
  32.  
  33. Remove the forward lamp relay center screws and position the relay center aside.
  34.  
  35. Remove the water pump pulley.
  36.  
  37. Remove the front cover bolts, noting their location for installation,
  38.  
  39. Separate the front cover from the engine block. Use care when working with light alloy parts. Discard the gasket.
  40.  



Click image to see an enlarged view

Fig. Exploded view of the engine front cover-3.4L (VIN X) engine



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Fig. Engine front cover bolt positions-3.4L (VIN X) engine

To install:

  1. Clean all parts well. Use care not to damage the sealing surfaces.
  2.  
  3. Apply sealer GM #1052080, or equivalent, to the lower edges of the sealing surfaces on the front cover. Using a new gasket, install the front cover. Apply the same sealer to the front cover bolts and install the front cover bolts, taking care the bolts are returned to their original locations. Tighten the bolts enough to pull the cover against the engine block. Do not finish tightening the bolts at this time.
  4.  
  5. Install the water pump pulley.
  6.  
  7. Install the oil cooler hose at the front cover.
  8.  
  9. Install the forward lamp relay center screws.
  10.  
  11. Install the upper alternator retaining bolts.
  12.  
  13. Install the intermediate drive shaft sprocket.
  14.  
  15. Raise and safely support the vehicle.
  16.  
  17. Final torque the front cover bolts. The large bolts should be tightened to 35-37 ft. lbs. (47-50 Nm) and the small bolts to 18-20 ft. lbs. (27-25 Nm).
  18.  
  19. Install the oil pan retainer bolts using the procedures found in this section.
  20.  
  21. Install the crankshaft balancer using the procedures found in this section.
  22.  
  23. Install the alternator and starter motor. Please see .
  24.  
  25. Install the remainder of the components in the reverse order of removal.
  26.  

3.5L Engine

WARNING
The factory recommended procedure for removing the timing chain engine front requires special lifting and support equipment. The steering shaft must be separated and the vehicle subframe must be loosened and lowered for access to the crankshaft balancer so the front cover can be removed. Careful work is required for reassembly. This is not a job for the inexperienced or ill-equipped.


NOTE
The crankshaft front oil seal can be replaced without removing the timing chain front cover.

  1. Disconnect the negative, then the positive battery cables.
  2.  
  3. Remove the right diagonal brace.
  4.  
  5. Remove the battery hold-down and remove the battery and the battery tray.
  6.  
  7. Remove the engine coolant reservoir (surge tank).
  8.  
  9. Reposition the underhood accessory wiring junction block for access.
  10.  
  11. Remove the drive belt. Please see .
  12.  
  13. Remove the drive belt idler pulley and the drive belt tensioner.
  14.  
  15. Drain the coolant into a suitable container.
  16.  
  17. Remove the water pump pulley bolts and pull off the pulley.
  18.  
  19. Remove the water pump bolts and the water pump drive belt shield.
  20.  
  21. Remove the water pump bolts and separate the pump from the engine. Note that bolt lengths vary. There are long and short bolts. Use care to note the length of bolts as they are removed and the location from which they were removed so they can be returned to their proper locations. Discard the gasket.
  22.  
  23. Raise and safely support the vehicle.
  24.  
  25. Remove the right front tire assembly. Locate and remove the right engine splash shield.
  26.  
  27. Place adjustable safety stands on the right side of the frame.
  28.  
  29. Remove the two right side frame bolts.
  30.  
  31. Lower the right side of the frame and engine using the adjustable safety stands to allow access to attach the three-legged puller to the crankshaft balancer. Remove the balancer following the procedures found in this section.
  32.  
  33. Remove the ten front cover perimeter bolts. Carefully separate the front cover from the engine. Use care. Both the front cover and the engine block are made of aluminum and are easily damaged.
  34.  



Click image to see an enlarged view

Fig. Front cover, gasket and important sealing points-3.5L (VIN H) engine



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Fig. Prying out the crankshaft front oil seal. The install a new seal should protrude 0.039-0.078 inch (1-2mm)-3.5L (VIN H) engine



Click image to see an enlarged view

Fig. This type of seal installer threads into the crankshaft and then presses the seal into place-3.5L (VIN H) engine

To install:

  1. Clean all parts well. Some gasket material may remain on the engine block. Use care when scraping gasket material from the front cover, engine block and the water pump. GM recommends a plastic scraper. Do not gouge aluminum parts. Clean the bolt threads well. The torque specification is low and if the bolt threads are dirty, an accurate torque is not possible and leaks are likely to develop.
  2.  
  3. Place a short bead of RTV sealant, GM #12345739, or equivalent, on the engine block as illustrated. Align the front cover gasket to the front cover bolt holes and insert two bolts through the front cover to hold the gasket in position. Install the front cover and gasket hand start all of the front cover retaining bolts. Evenly tighten the bolts to 124 inch lbs. (14 Nm).
  4.  
  5. Install the crankshaft balancer following the procedures found in this section.
  6.  
  7. Jack the cradle back into position. Install the cradle bolts side bolts and remove the cradle support.
  8.  
  9. Using a new gasket, install the water pump to the front cover. Install the cleaned and lightly lubricated water pump bolts finger-tight, then torque to 124 inch lbs. (14 Nm).
  10.  
  11. Install the water pump pulley and bolts and finger-tighten the bolts.
  12.  
  13. Install the idler pulley and bolt. Tighten the idler pulley bolt to 37 ft. lbs. (50 Nm).
  14.  
  15. Install the drive belt, then, with the drive belt holding the pulley from turning, torque the water pump pulley bolts to 18 ft. lbs. (25 Nm).
  16.  
  17. Install the remaining components in the reverse order of the removal process. When refilling the cooling system, use the proper mix of DEX-COOL® and water. Check for leaks.
  18.  

3.8L Engines

NOTE
The crankshaft front oil seal can be replaced without removing the timing chain front cover.

  1. Disconnect the negative battery cable.
  2.  
  3. Drain the cooling system into a suitable container.
  4.  
  5. Remove the drive belt. Please see . Remove the drive belt tensioner.
  6.  
  7. Remove the crankshaft balancer using the procedures found in this section.
  8.  
  9. Detach the electrical connections from the front cover.
  10.  
  11. Remove the crankshaft position sensor shield and remove the crankshaft position sensor.
  12.  
  13. Remove the oil pan to front cover bolts.
  14.  
  15. Remove the oil filter.
  16.  
  17. Remove the lower radiator hose.
  18.  
  19. Remove the water pump pulley.
  20.  
  21. Remove the front cover attaching bolts and separate to front cover and oil filter adapter as one assembly from the engine block. Discard the gasket.
  22.  



Click image to see an enlarged view

Fig. Exploded view of the front cover and crankshaft seal arrangement-3.8L engines

To install:

  1. Clean all parts well, especially the gasket sealing surfaces. Clean the sealing surfaces with a degreaser. Inspect the front cover seal for damage. If the front seal is to be replaced, use the following procedure:
    1. Note that the crankshaft front oil seal can be replaced without removing the timing chain front cover.
    2.  
    3. With the front cover on or off the engine, after removing the crankshaft balancer, pry the seal out with an appropriate prying tool. Use care not to scratch the crankshaft or damage the seal bore.
    4.  
    5. Inspect the crankshaft, the balancer and the front cover for scratches. Replace or repair as necessary.
    6.  
    7. Lubricate the replacement crankshaft seal with clean engine oil to make installation easier.
    8.  
    9. A seal driver is recommended. Install the seal making sure the seal lip faces the engine. Tap into place with a seal driver. Support the aluminum cover underneath to prevent distortion and do not hammer on the seal. Tap in lightly until it seats.
    10.  

  2.  
  3. If the front cover is being replaced with a new service replacement part, transfer the oil filter adapter, pressure relief valve and water pump to the new cover.
  4.  
  5. Inspect the timing chain for overall in and out movement. Maximum movement is 1 inch (25.4mm). Inspect the sprockets for wear.
  6.  


NOTE
The oil pan can be dropped slightly for front cover clearance if all pan bolts are loosened and the oil level sensor is removed.

  1. With all sealing surfaces clean, install a new front cover gasket. Apply sealer GM #1052080, or equivalent, to the bolt threads. Install the front cover taking care to align the cogs on the crankshaft sprocket with the cogs on the oil pump in the front cover. When satisfied with the fit and alignment, install the upper front cover bolts finger-tight. Using a torque angle meter, tighten the bolts to 11 ft. lbs. (15 Nm) plus an additional 40 degrees.
  2.  
  3. Inspect the oil pan gasket and replace, if necessary. Install the oil pan to front cover bolts and tighten any oil pan bolts that were removed. Tighten the bolts to 125 inch lbs. (14 Nm).
  4.  
  5. Install the water pump pulley, and the lower radiator hose.
  6.  
  7. Install a new oil filter. Carefully install the crankshaft position sensor and the sensor shield.
  8.  
  9. Install the remainder of the components in the reverse order of removal.
  10.  
  11. Refill the engine with oil and the cooling system with the proper mix of DEX-COOL® and water.
  12.  

 
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