Allis-Chalmers C - Crankshaft and Bearings

ALLIS-CHALMERS
Crankpin diameter ... .1.499-l.SOO
Running clearance 001S-.002
Renew if clearance
exceeds 004
Side clearance 006-.010
Renew if side clearance
exceeds 014
Cap screw torque 20-2S ft. lbs.
CRANKSHAFT AND BEARINGS
All Except Model G
97. Shaft is supported on three
slip-in type bearings provided with
shims for a very limited range of ad-
justment. Bearings are renewable from
below without removing crankshaft.
Remove the engine to remove the
crankshaft.
To remove the front bearing shell
upper half on WC, WD, WD45, and WF
only, it will be necessary to first re-
move timing gear cover, so as to lower
shaft enough to disengage the shell
from locating dowel (3—Fig. AC42).
Loosen center and rear main bearing
caps and remove front main bearing
cap. Tap front main bearing upper half
down and away from dowel pin and ro-
tate shell around and off of crankshaft
journal. All mains may be renewed on
B, C, CA, and RC without disturbing
the timing gear cover.
For new bearing shells and crank-
shaft installation, use the standard
shim pack of four shims on each side
which will automatically provide the
correct running clearance and the cor-
rect bearing crush of .OOIS.
Bearings are available in .002S, .040,
.042S and .04S undersize as well as
standard for service.
Oil wick (5—Fig. AC41 or AC42) for
shaft pilot bearing lubrication which is
inserted in the center of the rear
main bearing journal can be renewed
after removing engine clutch and oil
pan. Insert wick from rear of journal
and avoid stretching as a stretched
wick will permit an excessive amount
of oil to pass. The wick should be fiush
with front face of journal and extend
1 2
Paragraphs 97-98
5
Fig, AC41-Models B, C, CA, and RC crankshaft assembly rotates on three slip-in typm
bearings which are provided with shims for a very limited range of ad'iustment.
1, Pulley
2. Set Bcrew
3. Crankshaft gear
4. Key
5. Pilot bushinsr wick
6. Flywheel
7. Pilot bushing
8. Pulley key
11 10
Fig, AC42-Models WC, WD, and WF crankshaft assembly. Front main bearing dowel (3)
is used to prevent rotation of upper half of flanged front main bearing. Clutch pilot
bearing wick (5) is not used in WD engines after W253200, and all WD45 engines.
1. Gear key
2. Crankshaft gear
5. Bearing dowel pin
6. Wick
7. Rear oil seal
8. Lower bearing insert
9. Front oil se«]
10. Pulley lock screw
from the rear only enough to contact
the clutch shaft. On WD beginning
with engine W310920 and WD4S mod-
els the crankshaft has no oil wick or
clutch shaft pilot bearing.
BEARING ADJUSTMENT. Crank-
shaft main bearing shims which are
provided for a very limited range of
adjustment do not fit between the
bearing sliell parting surfaces, but only
between the bearing cap and its mat-
ing surface, as shown in Fig. AC40.
Refer to paragraph 9S for further in-
formation.
Fig, AC40-Models B,
C, CA, kC, WC, WD,
WD45 & WF main
bearing shell installa-
tion. Note that shims
do not fit between
bearing shell parting
surfaces. Connecting
rod bearing construe*
tion and adiustment
are similar.
Check the crankshaft journals for
wear, scoring and out-of-round con-
dition against the values listed below:
B-C WC
CA WD
WD45
Journal Diameter: RC WF
Front (mean) 2.249S 2.436
Center & rear (mean) 2.249S 2.477S
Running clearance 1-2 2-3
Crankpin
diameter (mean) ... 1.937 2.374S
WC (prior #366S)... 1.9995
Renew or regrind if out-
of-round more than.. .002S .0025
Mains bolt torque
(ft. lbs.) 80 85
Model G
98. Shaft is supported on two
shimless, non-adjustable, slip-in, pre-
cision type main bearings, renewable
from below, without removing the
crankshaft. Bearing caps are installed
with the numbers facing the camshaft.
Crankshaft end play is controlled by
shims (9—Fig, AC43), at number one
journal and should be checked with
all parts in place, including the crank
jaw. Recommended end play is .003-
21