Bearing shells should be marked to indicate top or bottom and number of the rod
Remove connecting rod setscrews, caps, and bearing shells (see paragraph 5-18).
The bearing seal half housing setscrews must be removed to remove the rear
main bearing cap.
(7) Remove main bearing cap.
(8) Remove crankshaft (2, Appendix F, Figure 52).
(9) Remove top half of main bearing shells (5).
(10) Remove top half of oil seal housing (20, Appendix F, Figure 49).
Crankshaft Installation (see Appendix E Figure 52).
· Ensure that the crankshaft oil ports are unplugged.
· Unless the bearing shells are being replaced they must be Installed In their
(1) Install three top bearing shells (5, Appendix F, Figure 52) and lubricate them with clean engine oil.
(2) Set crankshaft (2) in place.
(3) Install upper thrust washer (see Figure 5-14).
(4) Install three lower bearing shells (5) and lubricate them with clean engine oil.
(5) Install main bearing cap.
Ensure that the two lower thrust washer halves are located correctly on either side
of the rear main bearing.
(6) Check the main bearing setscrews for signs of stretch or thread damage. Replace the setscrews if
(7) Install setscrews and torque to 85 lb.-ft. (115 Nm).
If the crankshaft end float is not within limits, install oversized thrust washers.
(8) Ensure that the crankshaft (2) rotates freely. Check the crankshaft end float with feeler gage.
Acceptable end float is 0.002-0.015 (see Figure 5-15).
(9) Install new sealing strips to the rear main bearing oil seal housing (see paragraph 5-16/).
(10) Oil crankpins with clean engine oil and install connecting rod bearing shells. Ensure that they are
returned to their correct positions. Install connecting rod caps (see paragraph 5-18).
(11) Install oil pump and oil pan assembly. Replace gaskets and seals (see paragraph 5-21).
(12) Install timing case back plate, injector pump drive hub, timing gears, timing gear cover, and crankshaft
pulley (see paragraph 5-19).
(13) Install and align flywheel housing and flywheel (see paragraph 5-17).
(14) Install starter and solenoid (see paragraph 4-52).
Rear Oil Seal Installation.
This sealing arrangement consists of two half housings bolted around the rear of the crankshaft. The
bore of these housings is machined to accommodate a rubber cored asbestos strip that, in conjunction
with a right-hand helix machined between the thrust collar and the flywheel mounting flange, acts to
return the surplus oil reaching the seal. The two half housings fit over this helix. The contact of the
sealing strips with the crankshaft prevents leakage beyond this point.
When traces of oil become apparent from behind the flywheel and a faulty rear oil seal is suspected, first
ensure that the crankcase is breathing normally. Any buildup in crankcase pressure could cause oil to be
forced past the rear sealing arrangement.