6.6.4 Engine Maintenance.
The main bearings are of the thin-shell type.
installation requires that webs in crankcase be in
alignment and for bearing bores to be preloaded. No
attempt should be made to adjust or recondition bearing
Check bearing bores as follows:
(1) position bearing caps, making sure that their identification numbers
match with those stamped in crankcase.
Torque down bolts in accordance
with appendix G.
(2) Using inside micrometer, measure each main bearing base at points 1 and 2
in plan "a", then in the same manner in plane "b" offset by 90 degrees
(see figure 6-14), in order to determine any contraction, out-of-
roundness or conicity.
See table 6-1 for wear limits.
(3) Install new bearings.
(4) Position bearing cap, then preload and torque according to instructions
given in Table 6-1.
(5) Using inside micrometer, measure each bearing bore and compare
measurements to table 6-1.
Install deflector plate (figure 6-11, 11), notched nail (10) and sleeve
Install plug (8), washer (7), nozzle (6), plug (5), washer (4), and plug (3).
Install two washers (2) and plugs (1).
Install crankshaft (figure 6-10, 9) as follows:
Check locating pin in crankcase gearwheel.
It should project 0.67 inch
(17mm) from side opposite bearing identification mark. If necessary
install new locating pin.
Install crankcase gearwheel with face bearing identification mark
directed away from crankshaft (9).
Install bearing halves (10) and bearing caps (6 and 7), making sure that
identification marks are correct.
Coat ring stops (11 and 12) with grease and stick them by their smooth
faces to first bearing web and first bearing cap.
Install eight dowel bushings (8).
Using oil, lubricate crankshaft journels and install crankshaft (9) with
crankshaft gear match mark positioned.
Ensure bearing shells are seated in main bearing caps and bearing webs.