TM 5-3895-376-14&P
5-20. CRANKSHAFT MAINTENANCE INSTRUCTIONS - Continued
measurement exceeds 1.1929 in. (30.300 mm),
replace the crankshaft assembly.
7.
Check for approximate radial end play of crank-
shaft at front main bearing as follows:
a.
Using vernier caliper, measure diameter (D1)
on crankshaft main bearing journal and re-
cord as X.
b.
With vernier caliper, measure inside diameter
of front main bearing still installed in the en-
gine housing and record as Y.
c.
Subtract X from Y value. If result is greater
than 0.0039 in. (0.10 mm), replace the crank-
shaft (10), and forward defective crankshaft
to general support maintenance.
NOTE
If radial end play is greater than 0.0039 in.
(0.10 mm), perform inspection of the front
main bearing as described in paragraph 5-
21.
8.
Radial end play at the connecting rod journal
(D2) is measured as instructed in paragraph 5-
13. If radial end play exceeds 0.0043 in. (0.110
mm), replace the crankshaft (10), and forward de
fective crankshaft to general support mainte-
nance.
INSTALLATION
NOTE
If you are installing a repaired crankshaft,
it is necessary to determire the proper
size front main bearing and connecting rod
bearings to use. Undersize bearings are
available for use when repaired crankshaft
has been properly reground. Table 5-1 pro-
vides dimensional data to determine cor-
rect size of undersized bearings to install.
Bearing
Journal
Front Main
Bearing
(D1)
1.
Lay the assembled seal housing (3) down on a
clean bench surface with the seal side up.
2.
install replacement seal (9), with seal lip towards
bearing, in seal housing (3), using an arbor press
with a pressing sleeve (at least 3.375 in. (85 mm)
RADIAL BEARING PLAY
NEW PARTS
MAX. LIMIT
D1
0.0004 - 0.0024 in.
0.0039 in.
(0.011 - 0.06 mm)
(0.10 mm)
D2
0.0012 - 0.0024 in.
0.0043 in.
(0.030 - 0.060 mm)
(0.110 mm)
Table 5-1. Crankshaft Undersized Bearing
Connecting
R o d
Bearing
(D2)
Selection Chart.
MIM.
MAX.
Bearing
Diameter
Diameter
Part
Number
1.5673 in.
1.5681 in.
775.033.04
(39.810 mm) (39.830 mm)
1.5575 in.
1.5583 in.
775.034.4
139.560 mm) (39.580 mm)
1.5657 in.
1.5661 in.
470.009.4
(39.770 mm) (39.780 mm)
5-59
