Jeep UNIVERSAL CJ-2A - Page 43

D
L4-134 ENGINE
D-60. Crankshaft Rear Bearing Seal
Oil leakage through the rear main bearing is pre-
vented by a metal supported neoprene lip type
seal which can readily be installed without remov-
ing the crankshaft.
Should trouble be experienced with oil leaking
from the rear main bearing there are several points
which should be checked.
a. Be sure that the identifying paint daub on the
bearing cap is the same as that appearing on the
center bearing web.
b. The bearing to crankshaft clearance must not
exceed .0029" [0,0736].
c. Place sealer on the faces of the rear bearing cap
from the rear oil groove to the oil seal grooves.
d. Be sure the rubber oil seals extend about .74:"
[6 mm.] below the bottom face of the cap.
e. Be sure the oil pan gasket is not leaking.
f. Check to be sure the oil leak is not at the cam-
shaft rear bearing expansion plug or from the
crankcase.
D-61. Floating Oil Intake
The floating oil intake is attached to the bottom
of the crankcase with two screws. The float and
screen causes it to ride, raise and lower with the
amount of oil in the pan. This prevents water or
dirt, which may have accumulated in the bottom
of the oil pan, from circulating through the engine
because the oil is drawn horizontally from the top
surface. Whenever removed, the float, screen, and
tube should be cleaned thoroughly to remove any
accumulation of dirt. Also clean the oil pan.
Fluctuating oil pressure can usually be traced to
an air leak between the oil float support and the
crankcase.
Be sure the float support flange is flat. Clean both
the flange and the crankcase surfaces thoroughly
before installing a new gasket. Be sure the retaining
screws are tight.
42
FIG. 51-FLOATING OIL INTAKE AND PAN
1-0il Float
2-Gasket
3-0il Float Support
4-Sc:rew and Lockwasher
5-Qil Pan Gasket
6-0il Pan .
7-Bolt and Lockwasher
8-Drain Plug
9-Drain Plug Gasket
D-62. Oil Pump
The oil pump is located externally on the left side
of the engine. In operation oil is drawn from the
crankcase through the floating oil intake then
passes through a drilled passage in the crankcase
to the pump from which it is forced through
drilled passages to the crankshaft and camshaft
bearings. When it is necessary to remove an oil
pump, first remove the distributor cover and note
the position of the distributor rotor so that the
pump may be reinstalled without disturbing the
ignition timing. To install the pump without dis-
turbing the timing, the pump gear must be cor-
rectly meshed with the camshaft driving gear to
allow engagement of the key on the distributor
shaft with the pump shaft slot, without changing
the position of the distributor rotor. Distributor
can be installed only in one position as the slot and
driving key are machined off-center.
Effective with engine S/N 44417 a different oil
pump was installed in production. The early pro-
duction pump shown in Fig. 53 and the later pro-
duction pump shown in Fig. 52 are similar in design.
The major differences are that the later pump
employs an inner and outer rotor within the pump
body in place of gears and that the oil relief valve
is mounted on the pump body instead of on the
cover. To disassemble the later type of pump, first
remove the gear which is retained by a gear retain-
ing pin. It will be necessary to file off one end of
the pin before driving it out with a small drift.
By removing the cover, the outer rotor and the
inner rotor and shaft may be removed through the
cover opening.
Failure of the pump to operate at full efficiency
may be traced to excessive end float of the rotors,
excessive clearance between the rotors, or excessive
clearance between the outer rotor and the pump
body.
Match the rotors together with one lobe of the
inner rotor pushed as far as possible into a notch
of the outer rotor. Measure the clearance between
the lobes of the rotors as shown in Fig. 54. This
clearance should be .010" [0,254 mm.] or less. If
more, replace both rotors. Measure the clearance
between th~ outer rotor and the pump body as
shown in Fig. 55. Should this clearance exceed .012"
[0,305
mm.] the fault is probably in the pump body
and it should be replaced.
End float of the rotors is controued by the thickness
of the cover gasket which is made of special material
that can be only slightly compressed. Check the
cover to be sure the inner surface is not rough
or scored and that it is flat within .001" [0,025 mm.].
Measure with feeler gauges as shown in Fig. 56.
Measure the thickness of the rotors which must
be within .001" of each other. Assemble the rotors
in the pump body and install the cover without
its gasket. When the cover screws are tightened to
normal tension there should be interference be-
tween the rotors and the cover making it impossible
to turn the pump shaft by hand. Remove the cover
and replace it with the gasket in position. The
rotors should then rotate freely, proving that end
float of the rotors is less than the thickness of the
gasket when compressed or .004" [0,102 mm.].