Rear Crankshaft Main Bearing Seal: Service and Repair

Fig. 13 Crankshaft rear oil seal installation. 1982 4-140 engine:

1982
1. Remove oil pan.
2. Remove rear main bearing cap.
3. Loosen remaining bearing caps, allowing crankshaft to drop down about {1-32} inch.
4. Install a sheet metal screw into seal and pull screw to remove seal.
5. Carefully clean seal groove in block with a brush and solvent. Also clean seal groove in bearing cap.
6. Dip seal halves in clean engine oil.
7. Carefully install upper seal half in its groove with locating tab toward rear of engine, Fig. 13, by rotating it on shaft journal of crankshaft until approximately {3-8} inch protrudes below the parting surface. Be sure no rubber has been shaved from outside diameter of seal by bottom edge of groove.
8. Retighten main bearing caps and torque to specifications.
9. Install lower seal in main bearing cap with undercut side of seal toward front of engine, and allow seal to protrude about {3-8} inch above parting surface to mate with upper seal upon cap installation.
10. Apply suitable sealer to parting faces of cap and block. Install cap and torque to specifications. If difficulty is encountered in installing the upper half of the seal in position, lightly lap (sandpaper) the side of the seal opposite the lip side using a medium grit paper. After sanding, the seal must be washed in solvent, then dipped in clean engine oil prior to installation.