Jeep cherokee 1989, Owner'S Manual

Page: 127 / 336

Chapter 2 Part D General engine overhaul procedures
2D-21
Bearing selection (four and six-cylinder engines)
Refer to illustrations and
8 If you have a four or six-cylinder engine and the oil clearances
are incorrect (see Section 22) or you are replacing the original bearings,
refer t o the accompanying charts t o select the correct new bearings
(see illustrations),
9
the crankshaft has been reground, new undersize bearings must
be installed. Disregard steps 1 1 through 1 3 and consult the automotive
machine shop that reground the crankshaft. They will provide or help
you select the correct size bearings.
1 0 Regardless of how the bearing sizes are determined, use the oil
clearance measured with Plastigage (see Section 22) as a guide t o en-
sure the proper size bearings are installed.
11 Four and six-cylinder engines are assembled at the factory
with various sizes of color-coded bearing inserts as listed in illustra-
tions through The color code appears on the edge of the
bearing insert.
1 2 The journal size codes are generally painted on the adjacent cheek
toward the flanged end (rear) of the crankshaft, except for the rear
main bearing journal, which is marked on the crankshaft rear flange.
1 3 To obtain a select fit, upper and lower bearing inserts of different
sizes may be used as
a pair, For example, a standard insert is sometimes
used in combination with a 0.001-inch undersize insert t o reduce
clearance by 0.0005-inch. Caution: Never use apair o f bearing inserts
with a greater size difference than 0.001 -inch. When replacing inserts,
the o d d sized inserts must be either all on the top or all on the bottom.
Crankshaft No. 1 Block No. 1
Journal Color and
Dlamrtrr In
2.5001 to 2.4996 (Standard)
(63.5025 to 63.4698 mm)
Bore Color
In (mm)
Yellow
-
2.6910
(66.3514 to 66.3641 mm)
Black
-
2.6915 to 2.6920
Color
Yellow
-
Standard Black
-
to 68.3768
Yellow Standard
I
Black
-
0,001-Inch
Underslze
-
(0.001 mm)
I
Underslze
Orange
-
2.4996 to 2.4991 (0.0005 Undersize)
(63.4898 to 63.4771 mm)
Black
-
0.001-Inch Black
Underslze (0.025 mm) Underslze (0,025 mm)
Yellow
-
2.6910 to 2.6915
(66.3514 to 68.3641 mm)
Black
-
2.6915 to 2.6920
(66.3461 to 66.3768
Black
-
2.4991 to 2.4966 (0.001 Underslze)
(63.4771 to 63.4644 mm)
Green
-
2.4986 to 2.4961 (0.0015 Underslze)
(63.4644 tc83.4517 mm)
Red
-
2.4901 to 2.4896
(63.2485 to 63.2358 mm)
G l o w - 2.6910 to 2.6915 Black
-
Black
-
0.001-Inch
(66.3514 to 66.3641 mm)
Black
-
2.6915 to 2.6920
(68.3461 to 68.3788
Yellow
-
2.6910 to 2.6915
(66.3514 to 68.3641
Yellow
-
2.6910 to 2.6915
(88.3514 to 68.3641 mm)
Underslze
-
(0.025 mm) Underslze
-
(0.025 mm)
I I
Black
-
Green
-
0.002-Inch
NOTE: Wlth Green and Red Coded Crankshaft Journals, Use Yellow Coded Cylinder Block Bores Only.
Red
-
0.010-Inch
Underslze (0.254 mm)
Red
-
Underslze
-
(0.254 mm)
Orange
-
to 2.4991 Underslze)
Yellow
-
Standard
(63.4896 63.4771
Journal
Color and Dlamrtrr In
(Journal
Yellow
-
2.5001 to 2.4996 (Standard)
(63.5025 to 83.4898 mm)
Black
-
0.001-Inch Underslze
I
Color
Green
-
2.4986 to 2.4961 Underslze) Black
-
0.001-Inch Underslze (0.025 mm) Green
-
0.002-Inch Underslze mm)
(63.4644 to 63.4517 mm)
Yellow
-
Standard
Black
-
2.4991 to (0.001 Underslze)
(63.4771 to 63.4844 mm)
Lowrr
Yellow
-
Standard
Main bearing selection chart
-
four-cylinder engines
Black 0.001-Inch Underslze (0.025 mm)
Red
-
2.4901 to 2.4896 (0.010 Underslze)
(63.2485 to 63.2358
Black
-
0.001-Inch Underslze (0.025 mm)
Red
-
0.010-Inch Underslze (0.054
I
Red
-
Underslze (0.254 mm)
The Motor Manual Guy