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    Ford Taurus/Sable 1986-1995 Repair Information

    Crankshaft and Main Bearings

    Print

    REMOVAL & INSTALLATION



    2.5L Engine

    See Figures 1, 2 and 3

    1. Disconnect the negative battery cable, then drain the engine oil.
    2.  
    3. Remove the engine from the vehicle, then place it on a work stand, then remove the oil level dipstick.
    4.  
    5. Remove the accessory drive pulley, if so equipped. Remove the crankshaft pulley attaching bolts and washer.
    6.  
    7. Remove the cylinder front cover and the air conditioning idler pulley assembly, if so equipped. Remove cover assembly.
    8.  
    9. Check the timing chain deflection. Remove the timing chain and sprockets.
    10.  
    11. Invert the engine on the work stand. Remove the flywheel and the rear seal cover. Remove the oil pan and gasket. Remove the oil pump inlet and the oil pump assembly.
    12.  
    13. Ensure all bearing caps (main and connecting rod) are marked so they can be installed in their original positions. Turn the crankshaft until the connecting rod from which the cap is being removed is up. Remove the connecting rod cap. Install a rubber hose onto the connecting rod bolts to prevent journal damage. Push the connecting rod and piston assembly up in the cylinder, then install the cap and nuts in their original positions. Repeat the procedure for the remaining connecting rod assemblies.
    14.  
    15. Remove the main bearing caps.
    16.  



    Click image to see an enlarged view

    Fig. Fig. 1: Remove the main bearing caps by removing the retaining bolts

    1. Carefully lift crankshaft out of the block so the upper thrust bearing surfaces are not damaged. Reinstall the main bearing caps on the block.
    2.  

    Handle the crankshaft with care to avoid possible fracture or damage to the finished surfaces.

    Click image to see an enlarged view

    Fig. Fig. 2: Exploded view of the crankshaft and the related components-2.5L engine

    To install:

    If the bearings are to be reused they should be identified to ensure that they are installed in their original position.

    1. Remove the main bearing inserts from the block and bearing caps.
    2.  
    3. Remove the connecting rod bearing inserts from the connecting rods and caps.
    4.  
    5. Install a new rear oil seal in the rear seal cover.
    6.  
    7. Apply a thin coat of Ford Polyethylene Grease D0AZ-19584-A (ESR-M1C159-A or ESB-M1C93-A) or equivalent, to the rear crankshaft surface. Do not apply sealer to the area forward of oil sealer groove. Inspect all the machined surfaces on the crankshaft for nicks, scratches or scores which could cause premature bearing wear.
    8.  
    9. If the crankshaft main bearing journals have been refinished to a definite undersize, install the correct undersize bearings, usually 0.25mm, 0.50mm, 0.80mm undersize. Ensure the bearing inserts and bearing bores are clean. Foreign material under the inserts will distort the bearing and cause a failure.
    10.  
    11. Place the upper main bearing inserts in position in the bores with the tang fitted in the slot provided.
    12.  

    Lubricate the bearing surfaces with Oil Conditioner part No. D9AZ-19579-CF or equivalent. Conditioner is needed for lubrication at initial start up.

    1. Install the lower main bearing inserts in the bearing caps.
    2.  
    3. Carefully lower the crankshaft into place.
    4.  
    5. Check the clearance of each main bearing. Select fit the bearings for proper clearance.
    6.  
    7. After the bearings have been fitted, apply a light coat of oil conditioner to journals and bearings. Install all the bearing caps and torque to proper specifications. Tighten the main bearing cap bolts to 52-66 ft. lbs. (70-90 Nm) and the connecting rod cap nuts to 21-26 ft. lbs. (28-35 Nm).
    8.  

    The main bearing caps must be installed in their original positions.

    Click image to see an enlarged view

    Fig. Fig. 3: Torque the main bearing cap bolts to specification

    1. Align the upper thrust bearing.
    2.  
    3. Check the crankshaft end play, using a dial indicator mounted on the front of the engine.
    4.  
    5. If the end play exceeds specification, replace the upper thrust bearing. If the end play is less than the specification, inspect the thrust bearing faces for damage, dirt or improper alignment. Install the thrust bearing and align the faces. Check the end play.
    6.  
    7. Install the new bearing inserts in the connecting rods and caps. Install rubber hoses on the rod bolts to prevent crankshaft journal damage. Check the clearance of each bearing using a piece of Plastigage®.
    8.  
    9. If the bearing clearances are to specification, apply a light coat of Oil Conditioner part No. D9AZ-19579-CF to the journals and bearings.
    10.  
    11. Turn the crankshaft throw to the bottom of the stroke. Push the piston all the way down until the rod bearings seat on the crankshaft journal.
    12.  
    13. Install the connecting rod cap and nuts. Torque the nuts to specifications
    14.  
    15. After the piston and connecting rod assemblies have been installed, check all the connecting-rod-crankshaft journal clearances using a piece of Plastigage®.
    16.  
    17. Turn the engine on the work stand so the front end is up. Install the timing chain, sprockets, timing chain tensioner, front cover, oil seal and the crankshaft pulley.
    18.  
    19. Clean the oil pan, oil pump and the oil pump screen assembly.
    20.  
    21. Prime the oil pump by filling the inlet opening with oil and rotating the pump shaft until oil emerges from the outlet opening. Install the oil pump. Install the oil pan.
    22.  
    23. Position the flywheel on the crankshaft. Apply Pipe Sealant with Teflon D8AZ-19554-A (ESG-M4G194-A and ESR-M18P7-A) or equivalent oil resistant sealer to the flywheel attaching bolts using a cross tightening sequence. Torque the bolts to 54-64 ft. lbs. (73-87 Nm).
    24.  

    On the flywheel, if equipped with manual transmission, locate clutch disc and install pressure plate.

    1. Turn the engine on the work stand so the engine is in the normal upright position. Install the oil level dipstick. Install the accessory drive pulley, if so equipped. Install and adjust the drive belt and the accessory belts to specification.
    2.  
    3. Remove the engine from work stand. Install the engine in the vehicle. Fill the crankcase with the correct amount and type of oil, then connect the negative battery cable.
    4.  

    3.0L Engine-Except SHO

    See Figures 4 and 5

    1. With the engine removed from the vehicle and placed on a workstand, loosen the idler pulley and the alternator belt adjusting bolt.
    2.  
    3. Remove the oil pan and gasket.
    4.  
    5. Remove the front cover assembly.
    6.  
    7. Check the timing chain deflection. Remove the timing chain and sprockets.
    8.  
    9. Invert the engine on the workstand. For vehicles through 1993, remove the flywheel. For 1994-95 vehicles remove the pushrod. Remove the oil pump inlet and the oil pump assembly.
    10.  
    11. Ensure all bearing caps (main and connecting rod) are marked so that they can be installed in their original positions. Turn the crankshaft until the connecting rod from which the cap is being removed is up. Remove the connecting rod cap. Push the connecting rod and piston assembly up in the cylinder. Repeat the procedure for the remaining connecting rod assemblies.
    12.  
    13. Remove the main bearing caps.
    14.  

    Handle the crankshaft with care to avoid possible damage to the finished surfaces or the engine.

    1. Carefully lift the crankshaft out of the block so that the upper thrust bearing surfaces are not damaged.
    2.  



    Click image to see an enlarged view

    Fig. Fig. 4: Exploded view of the crankshaft, main bearing caps, and bearings-3.0L engine (except SHO)

    To install:

    If the bearings are to be reused they should be identified to ensure that they are installed in their original positions.

    1. Remove the main bearing inserts from the block and bearing caps.
    2.  
    3. Remove the connecting rod bearing inserts from the connecting rods and caps.
    4.  
    5. Inspect all the machined surfaces on the crankshaft for nicks, scratches, scores, etc., which could cause premature bearing wear.
    6.  
    7. If the crankshaft main bearing journals have been refinished to a definite undersize, install the correct undersize bearings.
    8.  

    Ensure that the bearing inserts and the bearing bores are clean. Foreign material under the inserts will distort the bearing and cause a failure.

    1. Place the upper main bearing inserts into position in the bores with the tang fitted in the slot provided.
    2.  
    3. Install the lower main bearing inserts in the bearing caps.
    4.  
    5. Carefully lower the crankshaft into place.
    6.  
    7. Check the clearance of each main bearing. Select fit the bearings for proper clearance.
    8.  
    9. After the bearings have been fitted, apply a light coat of Oil Conditioner part No. D9AZ-19578-CO or heavy engine oil, SAE 50 weight, to the journals bearings and rear seal surface. Install all the bearing caps. Apply RTV to the gap between the rear main bearing and the block. Take care to keep RTV from the parting surfaces between the block and the cap.
    10.  

    Ensure the main bearing caps are installed in their original positions and orientation.

    1. Lubricate the journal with oil conditioner or heavy engine oil 50 SAE weight. Install the thrust bearing cap with the bolts finger-tight. Pry the crankshaft forward against the thrust surface of the upper half of the crankshaft thrust main bearing. Hold the crankshaft cap to the rear. This will align the thrust surfaces of both halves of the bearing to be positioned properly. Retain the forward pressure on the crankshaft. Tighten the cap bolts to 55-63 ft. lbs. (75-85 Nm).
    2.  



    Click image to see an enlarged view

    Fig. Fig. 5: Crankshaft bearing alignment-3.0L engine (except SHO)

    1. Check the crankshaft end play with a dial indicator mounted on the front of the engine.
    2.  
    3. If the end play exceeds specification, replace the upper and lower thrust bearings. If the end play is less than specification, inspect the thrust bearing faces for damage, dirt or improper alignment. Install the thrust bearing and align the faces. Recheck the end play.
    4.  
    5. Install the new bearing inserts in the connecting rods and caps. Check the clearance of each bearing by using a piece of Plastigage®.
    6.  
    7. If the bearing clearances are to specification, apply a light coat of Oil Conditioner part No. D9AZ-19579-C or heavy engine oil, SAE 50 weight, to the journals and bearings.
    8.  
    9. Turn the crankshaft throw to the bottom of the stroke. Push the piston all the way down until the rod bearings seat on the crankshaft journal.
    10.  
    11. Install the connecting rod cap.
    12.  
    13. After the piston and connecting rod assemblies have been installed, check all the connecting rod crankshaft journal clearances using a piece of Plastigage®.
    14.  
    15. Turn the engine on the work stand so that the front end is up. Install the timing chain, sprockets, front cover, new oil seal and crankshaft pulley. Turn the engine on the work stand so that the rear end is up. Install the rear oil seal.
    16.  
    17. Clean the oil pan, oil pump and the oil pump screen assembly.
    18.  
    19. Prime the oil pump by filling the inlet opening with oil and rotating the pump shaft until the oil emerges from the outlet opening. Install the oil pump, baffle and oil pan.
    20.  
    21. Position the flywheel on the crankshaft. Tighten to 54-64 ft. lbs. (73-87 Nm).
    22.  
    23. Turn the engine on work stand so that the engine is in the normal upright position. Install the accessory drive pulley. Install and adjust the accessory drive belts to specification.
    24.  
    25. Install the torque converter, as required.
    26.  
    27. Remove the engine from the work stand. Install the engine in the vehicle.
    28.  

    3.8L Engine

    See Figure 6

    If the bearings are to be reused, they should be identified to ensure that they are installed in their original positions.

    1. Disconnect the negative battery cable, then drain the engine oil. Remove the engine from the vehicle and mount it on a suitable work stand.
    2.  
    3. Tag and disconnect the ignition wires from the spark plugs, then remove the distributor cap and ignition wires as an assembly. Remove the spark plugs.
    4.  
    5. On Taurus Police vehicles, remove the oil pan baffle.
    6.  
    7. Remove the oil pan and oil pickup tube.
    8.  
    9. Remove the front cover and water pump as an assembly.
    10.  
    11. Remove the distributor drive gear,.
    12.  
    13. Remove the camshaft and crankshaft sprockets and the timing chain.To do this: pull back on the ratcheting mechanism of the timing chain vibration damper, then install the pin through the hole to relieve the tension against the chain.
    14.  
    15. Remove the flywheel and the engine rear cover.
    16.  
    17. Remove the connecting rod bearing nuts and caps. Identify each bearing cap to insure that they are installed in their original positions. Push the pistons up into the cylinder and put pieces of rubber hose on the connecting rod bolts so the crankshaft journals do not get damaged.
    18.  
    19. Inspect all the machined surfaces on the crankshaft for nicks, scratches, scores, etc., which could cause premature bearing wear.
    20.  

    Because the engine crankshaft incorporates deep rolling of the main journal fillets, journal refinishing is limited to 0.25mm undersize. Further refinishing may result in fatigue failure of the crankshaft. Ensure the bearing inserts and the bearing bores are clean. Foreign material under the inserts will distort the bearing and cause a failure.

    1. Remove the main bearing caps and identify each bearing cap to insure that they are installed in their original positions.
    2.  
    3. Carefully lift the crankshaft out of the block to prevent damage to bearing surfaces. Remove rear oil seal and discard. Before installation, lightly oil all bolt and stud threads.
    4.  



    Click image to see an enlarged view

    Fig. Fig. 6: Exploded view of the crankshaft, main bearing caps and bearings-3.8L engine

    To install:
    1. Make sure all crankshaft bearing journals and bearing caps are clean. Contaminants under a bearing will cause distortion. Contaminants on the bearing surface will cause damage to the bearing journals.
    2.  
    3. If the crankshaft journals have been refinished to a definite undersize, make sure the proper undersize is being used.
    4.  
    5. Install the used main bearings to their original positions. If using new ones, install the tabs on the bearings into the slots in the cap and the block.
    6.  
    7. Carefully lower crankshaft into position in the cylinder block. Be careful not to damage the thrust bearing surfaces.
    8.  
    9. Apply a 3mm bead of Silicone Sealer part No. D6AZ-19562-A or equivalent to the rear main bearing cap-to-cylinder block parting line.
    10.  
    11. Lubricate the bearing surfaces and journals with Oil Conditioner part No. D9AZ-19579-CF or equivalent heavy engine oil 50 SAE weight.
    12.  
    13. Install the main bearing caps in the proper direction. Tighten the retaining bolts as follows:
      1. Do NOT jam the pry bar into position. Carefully tap on the pry bar until it holds the crankshaft toward the front of the engine. Wedge a pry bar between the cylinder block web and crankshaft cheek in front of the No. 3 crankshaft main bearing.
      2.  
      3. Tighten the main bearing cap retaining bolts to 65-81 ft. lbs. (88-110 Nm), then remove the prybar.
      4.  

    14.  
    15. Check crankshaft end-play. If the end play exceeds specification, replace the upper and lower thrust bearings. If the end play is less than specification, inspect the thrust bearing faces for damage, dirt or improper alignment. Install the thrust bearing and align the faces. Recheck the end play.
    16.  
    17. Install a new crankshaft rear oil seal.
    18.  
    19. Install the used connecting rod bearings to their original positions. If using new ones, install the tabs on the bearings into the slots in the cap and the rod.
    20.  
    21. Rotate the crankshaft as necessary to bring each throw to the lowest point of travel. Pull the piston downward until the connecting rod seats on the crank throw. Install the connecting rod caps and torque in three steps:
      1. Tighten retaining nuts to 31-36 ft. lbs. (42-49 Nm).
      2.  
      3. Loosen the nuts 2-3 turns.
      4.  
      5. Final tighten the nuts to 31-36 ft. lbs. (42-49 Nm).
      6.  

    22.  
    23. Install the timing chain assembly, distributor gear, oil pan baffle, oil pan, rear cover and flywheel, and spark plugs.
    24.  
    25. Install the distributor cap, then connect the ignition wires as tagged during removal.
    26.  
    27. Install the engine in the vehicle. Connect the negative battery cable, then fill the crankcase with the correct amount and type of engine oil.
    28.  

    CLEANING & INSPECTION



    See Figures 7, 8 and 9

    1. Clean the crankshaft with solvent and a brush. Clean the oil passages with a suitable brush, then blow them out with compressed air.
    2.  
    3. Inspect the crankshaft for obvious damage or wear. Check the main and connecting rod journals for cracks, scratches, grooves or scores. Inspect the crankshaft oil seal surface for nicks, sharp edges or burrs that could damage the oil seal or cause premature seal wear.
    4.  



    Click image to see an enlarged view

    Fig. Fig. 7: Checking the crankshaft for excessive run-out

    1. If the crankshaft passes a visual inspection, check journal run-out using a dial indicator. Support the crankshaft in V-blocks as shown in the figure and check the run-out as shown. Compare to specifications.
    2.  
    3. Measure the main and connecting rod journals for wear, out-of-roundness or taper, using a micrometer. Measure in at least 4 places around each journal and compare your findings with the journal diameter specifications.
    4.  
    5. If the crankshaft fails any inspection for wear or damage, it must be reground or replaced.
    6.  



    Click image to see an enlarged view

    Fig. Fig. 8: Checking the main bearing journal using a micrometer



    Click image to see an enlarged view

    Fig. Fig. 9: Checking main bearing bore diameter with the bearings installed

    BEARING REPLACEMENT



    See Figures 10 and 11

    The following procedure requires the use of Plastigage® or a micrometer set consisting of inside and outside micrometers, and a dial indicator.

    1. Inspect the bearings for scoring, chipping or other wear.
    2.  
    3. Inspect the crankshaft journals as detailed in the Cleaning and Inspection procedure.
    4.  
    5. If the crankshaft journals appear usable, clean them and the bearing shells until they are completely free of oil. Blow any oil from the oil hole in the crankshaft.
    6.  
    7. To check the crankshaft/rod bearing clearances using a micrometer, perform the following procedures:
      1. Set the crankshaft on V-blocks. Using a dial indicator set on the center bearing journal, check the crankshaft run-out. Repair or replace the crankshaft if out of specification.
      2.  
      3. Using an outside micrometer, measure the crankshaft bearing journals for diameter and out-of-round conditions; if necessary, regrind the bearing journals.
      4.  
      5. Install the bearings and caps, then torque the nuts/bolts to specifications. Using an inside micrometer, check the bearing bores in the engine block. If out of specification, regrind the bearing bores to the next largest oversize.
      6.  
      7. The difference between the two readings is the bearing clearance. If out of specification, inspect for the cause and repair as necessary.
      8.  

    8.  
    9. To inspect the main bearing surfaces, using the Plastigage® method, perform the following procedures:
    10.  

    NOTE: The journal surfaces and bearing shells must be completely free of oil to get an accurate reading with Plastigage®.

    Click image to see an enlarged view

    Fig. Fig. 10: Apply a strip of gauging material to the bearing, then install and tighten the cap



    Click image to see an enlarged view

    Fig. Fig. 11: As with the connecting rod bearings, remove the cap and compare the gauging material to the provided scale

    1. Place a strip of Plastigage® or equivalent gauging material, lengthwise along the bottom center of the lower bearing shell, then install the cap with the shell and torque the connecting rod nuts or main cap bolts to specification.When the Plastigage® material is installed on the bearing surfaces, DO NOT rotate the crankshaft.
    2.  
    3. Remove the bearing cap with the shell. The flattened Plastigage® will either be sticking to the bearing shell or the crankshaft journal.
    4.  
    5. Using the printed scale on the Plastigage® package, measure the flattened material at its widest point. The number on the scale that most closely corresponds to the width of the Plastigage® indicates the bearing clearance in thousandths of an inch or hundredths of a millimeter.
    6.  
    7. Compare your findings with the bearing clearance specification. If the bearing clearance is excessive, the bearing must be replaced or the crankshaft must be ground and the bearing replaced.NOTE: Bearing shell sets over standard size are available to correct excessive bearing clearance.
    8.  
    9. After clearance measurement is completed, be sure to remove the Plastigage® from the crankshaft and/or bearing shell.
    10.  
    11. For final bearing shell installation, make sure the connecting rod and rod cap and/or cylinder block and main cap bearing saddles are clean and free of nicks or burrs. Install the bearing shells in the bearing saddles, making sure the shell tangs are seated in the notches.
    12.  

    NOTE: Be careful when handling any plain bearings. Your hands and the working area should be clean. Dirt is easily embedded in the bearing surface and the bearings are easily scratched or damaged.

    CRANKSHAFT END-PLAY/CONNECTING ROD SIDE PLAY



    1. Place a prybar between a main bearing cap and crankshaft casting taking care not to damage any journals. Pry backward and forward, measure the distance between the thrust bearing and crankshaft with a feeler gauge.
    2.  
    3. Compare reading with specifications, 0.10-0.20mm. If too great a clearance is determined, a main bearing with a larger thrust surface or crank machining may be required. Check with an automotive machine shop for their advice.
    4.  
    5. Connecting rod clearance between the rod and crankthrow casting can be checked with a feeler gauge. Pry the rod carefully on one side as far as possible and measure the distance on the other side of the rod. Check the crankshaft and connecting rod specification table.
    6.  

     
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