Jeep Wrangler 1997 Manual page 703

TJ
REMOVAL AND INSTALLATION (Continued)
CAMSHAFT BEARINGS
The camshaft rotates within four steel-shelled,
babbitt-lined bearings that are pressed into the cyl-
inder block and then line reamed . The camshaft
bearing bores and bearing diameters are not the
same size . They are stepped down in 0 .254 mm
(0 .010 inch) increments from the front bearing (larg-
est) to the rear bearing (smallest) . This permits , eas-
ier removal and installation of the camshaft. The
camshaft bearings are pressure lubricated .
NOTE : It is not advisable to attempt to replace
camshaft bearings unless special removal and
installation tools are available.
Camshaft end play is maintained by the load
placed on the camshaft by the oil pump and distrib-
utor drive gear . The helical cut of the gear holds the
camshaft sprocket thrust face against the cylinder
block face .
CRANKSHAFT MAIN BEARINGS
REMOVAL
(1)
Disconnect negative cable from battery.
(2) Remove the spark plugs .
(3) Raise the vehicle .
(4) Remove the oil pan and oil pump .
(5) Remove only one main bearing cap and lower
insert at a time (Fig. 46) .
CONNECTING
ROD JOURNAL
MAIN BEARING CAPS
J8909-144
Fig. 46 Removing Main Bearing Caps and Lower
Inserts
(6)
Remove the lower insert from the bearing cap .
2 .5L ENGINE 9-41
(7)
Remove the upper insert by LOOSENING (DO
NOT REMOVE) all of the other bearing caps. Now
insert a small cotter pin tool in the crankshaft jour-
nal oil hole. Bend the cotter pin as illustrated to fab-
ricate the tool (Fig. 47) . With the cotter pin tool in
place, rotate the crankshaft so that the upper bear-
ing insert will rotate in the direction of its locking
tab. Because there is no hole in the No .3 main jour-
nal, use a tongue depressor or similar soft-faced tool
to remove the bearing insert (Fig. 47) . After moving
the insert approximately 25 mm (1 inch), it can be
removed by applying pressure under the tab .
(8) Using the same procedure described above,
remove the remaining bearing inserts one at a time
for inspection .
Fig. 47 Removing Upper inserts
INSTALLATION
(1)
Lubricate the bearing surface of each insert
with engine oil .
(2) Loosen all the main bearing caps . Install the
main bearing upper inserts .
(3) Install the lower bearing inserts into the main
bearing caps.
(4) Install the main bearing cap(s) and lower
insert(s) .
(5) Clean the rear main bearing cap (No .5) mating
surfaces .
(6) Apply Loctite 518, or equivalent on the rear
bearing cap (Fig. 48) . The bead should be 3 mm
(0.125 in) thick. DO NOT apply Loctite 518, or equiv-
alent to the lip of the seal .
(7) Install the rear main bearing cap. DO NOT
strike the cap more than twice for proper engage-
ment.