Crankshaft Main Bearings

NOTE: If crankshaft main bearings (6333) need to be replaced, crankshaft (6303) should be removed to check crankshaft journals for damage. Refer to Section 03-00 for inspection procedures.

Do not file or lap bearing caps or use shims to obtain the proper bearing clearance.

Bearings are available for service in standard sizes or 0.010 and 0.020 inch undersize. Refer to the Parts Catalog for the available sizes. Undersize bearings are available for use on journals that have been refinished.

If the rear main bearing is to be replaced, it will be necessary to remove the engine, install it on a work stand, replace the rear main bearing and replace the crankshaft rear oil seal (6701).

Removal

1. Drain the crankcase. Remove the oil pan (6675), oil pump (6600) and oil pump screen cover and tube (6622). Refer to Oil Pan and/or Oil Pump Screen Cover and Tube and to Oil Pump in the In-Vehicle Service portion of this section.

2. NOTE: Loosen all main bearing caps until just finger-tight. This will loosen the crankshaft and ease installation of new bearings.

   Replace one crankshaft main bearing at a time, leaving the other bearings securely fastened. Remove the main bearing cap to which new bearings are to be installed.

3. Insert Main Bearing Insert Tool TOOL-6331-E or equivalent in the oil hole in the crankshaft journal.

   

4. Rotate the crankshaft in the direction of engine rotation to force the bearing out of the cylinder block (6010).

5. Clean the crankshaft journal. When replacing standard bearings with new bearings, try to obtain the proper clearance with standard bearings or a combination of a standard bearing and a 0.010- or 0.020-inch undersize bearing.

Installation

NOTE: The upper and lower bearing halves are not interchangeable. The upper half is drilled and grooved to provide entry of oil.

1. Be sure bearings and surfaces are clean. Foreign material under the inserts will distort the bearings and cause premature wear.

2. To install the upper main bearing, place the plain end of the bearing over the shaft on the locking tang side of the cylinder block and partially install the bearing so that Main Bearing Insert Tool TOOL-6331-E or equivalent can be inserted in the oil hole in the crankshaft journal. With tool positioned in the oil hole, rotate the crankshaft slowly in the opposite direction of engine rotation until the bearing is seated. Remove the tool.

3. Check bearing clearance. Refer to Section 03-00.

4. NOTE: Select-fit the bearing for proper clearance. Refer to Section 03-00.

   When the bearing clearance has been found to be within specifications, apply a light coat of engine oil to the journal and bearings. Then, install the bearing cap.

5. Tighten the cap bolts to 82-94 Nm (60-69 lb-ft).

6. Repeat the procedure for the remaining bearings that require replacement.

7. If the thrust bearing cap (No. 5 main bearing) has been removed, install it as follows:

   1. Install the thrust bearing cap with the bolts finger-tight.
   2. Pry the crankshaft forward against the thrust surface of the upper half of the bearing.
   3. Hold the crankshaft forward and pry the thrust bearing cap to the rear. This will align the thrust surfaces of both halves of the bearing. Retain the forward pressure on the crankshaft.
   4. Tighten the cap bolts to 82-94 Nm (60-69 lb-ft).

      Thrust Bearing Cap Installation

      

8. If the rear main bearing is replaced (on a work stand), clean the mating surfaces of the bearing cap and the cylinder block with Ford Metal Surface Cleaner F4AZ-19A536-RA or equivalent meeting Ford specifications WSE-M5B392-A.

9. NOTE: When applying RTV sealant, always use the bead size specified and join the components within 15 minutes of application. After this amount of time, the sealant begins to set-up and its sealing effectiveness may be reduced.

   Apply a 1.6mm (1/16-inch) bead of RTV sealer, Silicone Rubber F4AZ-19562-B or equivalent meeting Ford specifications WSE-M4G323-A1 in each corner of the rear main bearing cap saddle the full length of the saddle. Be sure the main bearing is fitted and the cap bolts tightened to 82-94 Nm (60-70 lb-ft) before installing the new crankshaft rear oil seal.

10. Clean the oil pump screen cover and tube. Prime the oil pump by filling the inlet opening with oil and rotate the oil pump intermediate shaft (6A618) until the oil emerges from the outlet opening.

11. Install the oil pump and oil pan. Refer to Oil Pump and Oil Pan and/or Oil Pump Screen Cover and Tube in the In-Vehicle Service portion of this section.

12. Fill crankcase with oil specified in Section 00-03. Fill cooling system. Refer to Section 03-03. Start the engine (6007) and check for oil pressure. Operate the engine at fast idle and check for oil and coolant leaks.