
'Jeep'
UNIVERSAL
SERIES SERVICE
MANUAL
Dl
A 8
j
13415
FIG.
Dl-13—USING
PLASTIGAGE
TO
MEASURE
BEARING CLEARANCE
1— Plastigage
A—Start
2—
Scale
B—Flattened
install
cap with shell and tighten
bolts
80 to 110 lb-ft. [11,1 a 15,2 kg-m.] torque.
Caution:
Do not turn crankshaft with Plastigage
in
bearing.
b.
Remove bearing cap with bearing half. The
flattened Plastigage
will
adhere either to the bear ing half or the
journal.
Do not remove it.
c. Using the scale printed on the Plastigage en
velope,
measure Plastigage width at its widest
point. The number within the graduation which
most
closely corresponds to the width of Plasti
gage
indicates the bearing clearance in thousandths
of an inch.
DI-43.
Main Bearing
Fitting,
Feeler or
Shim
Stock
A
small strip of feeler or shim stock can be used
to check main bearing clearance. The method is
simple, but care must be taken to avoid damage
to the bearing surface from excessive pressure against the strip.
a.
Cut a rectangular piece of feeler or shim stock, .001"
[.0254
mm.] thick,
i/2"
[12,70
mm.] wide, and
Vs"
[3,175 mm.] shorter than the bearing width.
Position the bearing cap to the crankshaft journal
and
cylinder block, and install two cap
bolts
loosely.
b.
Tighten alternate cap bolts, a little at a time,
until
both have
been
tightened to 35 to 45 lb-ft. [4,8 a 6,2 kg-m.] torque.
c.
Turn
the crankshaft by hand, no more than one
inch
[2,5 cm.] in either direction.
Caution:
If the crankshaft is turned too far, it
will
embed the strip in the bearing surface.
This
will
damage the bearing and also cause a false indication of bearing clearance.
If
bearing clearance is correct, the strip should cause a light to heavy drag, or resistance to rotation.
If
there is little or no drag, clearance is too great;
if
the crankshaft cannot be turned, clearance is
insufficient. In either case, a different main bear ing must be
selected
to obtain proper clearance.
d.
Repeat
steps
a, b, and c, as necessary, to
select
proper main bearing size. After a bearing has
been
selected, remove the
test
strip from bearing on
crankshaft
journal surface; wipe both surfaces care
fully,
and apply clean
engine
oil to both surfaces. Position the bearing cap to the crankshaft journal
and
cylinder block, and install two cap
bolts
loosely.
Tighten
alternate cap bolts, a little at a time, to
final
specified torque of 80 to 110 lb-ft. [11,1 a 15,2 kg-m.]. The crankshaft should now rotate
freely.
Dl-44.
Piston
and
Connecting
Rod
Disassembly
a.
Remove two compression rings with a piston
ring
expander. To remove oil ring, remove the two
rails
and spacer-expander, which are separate
pieces
in
each piston third
groove.
b.
From
Tool Set W-338 use support base J-6047-1
with collar J-6047-5 and driver J-6047-4 with an
arbor
press to press piston pin from piston and con
necting rod. Mount support base and collar in press. Set driver in position and press out pin. Refer to
Fig.
Dl-14.
FIG.
Dl-14—PISTON
PIN
REMOVAL
1—
Arbor
Press
2—
Driver
3—
Piston
and Rod Assembly
4—
Collar
•
5—Support Base Dl-45.
Piston
and
Connecting
Rod
Cleaning
and Inspection
a.
Clean
carbon from piston surfaces and under
side of piston heads, and remove all pistons rings.
Clean
carbon from ring
grooves
with a suitable tool.
Remove any gum or varnish from piston skirts with a suitable solvent.
b.
Carefully examine pistons for rough or scored
bearing surfaces, cracks in
skirt
or head, cracked
or
broken ring lands, chipping and uneven wear 87

Pi
DAUNTLESS
¥-6
ENGINE
which
would cause rings to seat improperly or have
excessive clearance in
ring
grooves. Damaged or
faulty
pistons should be replaced,
c.
Inspect bearing surfaces of piston pins and check
for
wear by measuring worn and unworn surfaces
with
a micrometer. Rough or worn pins should be
replaced.
Test fit the piston pins in piston
bosses.
Occasionally,
a pin
will
be tight due to gum or
varnish
deposits.
This
may be corrected by remov
ing
the deposit with a suitable solvent. If piston
bosses
are worn out-of-round or oversize, the piston
and
pin assembly must be replaced. Oversize pins
are
not
practical,
since the pin must be a press fit
in
the connecting rod bore. Piston pins must fit the
piston with an easy finger push at
70°F.
[21°C.].
They
should have .0004" to .0007"
[0,0178
a
0,0102
mm.] clearance.
Dl-46.
Piston Fitting
If
cylinder bores are rebored or heavily honed,
new and possibly oversize diameter pistons must be
installed.
A new piston must be fitted to its cylinder
bore.
A satisfactory method of fitting pistons is as
follows.
a.
Expand
a
telescope
gauge
to fit the cylinder bore at right angles to the piston pin and
between
1
Vi"
to 2" [3,7 a 5,1 cm.] from the top.
b.
Measure diameter of the piston to be fitted, as
shown in
Fig.
Dl-15. The piston must be measured
at
right angles to the piston pin, W [6,3 mm.] below the oil
ring
groove. The piston must be be-
FIG.
Dl-15—MEASURING
PISTON
1—90°
tween .001" and .0015" [0,025 a
0,038
mm.]
smaller
than the cylinder bore.
Note:
Both cylinder block and piston must be at
very
nearly the same temperature when measure
ments are made or
errors
due to expansion
will
occur.
A difference of 10°F.
[5,6°C]
between
parts
is sufficient to produce a variation of .0009"
[0,0023
mm.].
The
pistons are cam-ground, which means that the
diameter at a right angle to the piston pin is
greater
than the diameter
parallel
to the piston
pin.
When a piston is checked for size, it must be
measured
with a micrometer applied to the
skirt
along a line
perpendicular
to axis of the piston pin.
Dl-47.
Piston Ring Fitting
When
new piston rings are to be installed without
reboring
cylinders,
the glazed cylinder walls should
be slightly dulled. However, cylinder bore diameter
should
not increase more than necessary.
Cylinder
walls
should be honed with the finest grade of
stone
to remove any glaze.
New compression rings must be checked for clear ance in piston
grooves
and for gap in cylinder bores;
however, the flexible oil rings are not checked for gap. The cylinder bores and piston
grooves
must
be clean, dry, and free of carbon and
burrs.
With
rings installed on piston, check clearance in
grooves
by inserting feeler
gauge
between
each
ring
and
its lower
land.
Any
ring
groove
wear
will
form
a
step
at inner portion of the lower
land.
If the
piston
grooves
have worn enough that relatively
high
steps
exist on the lower lands, the piston
should
be replaced because the
steps
will
interfere
with
proper operation of new rings and the
ring
clearances
will
be excessive. Piston rings are not
furnished
in oversize widths to compensate for
ring
groove
wear.
When
fitting new rings to new pistons, the side
clearance
of the compression rings should be .002" to .0035"
[0,051
a
0,089
mm.] for number one (1)
ring,
.003" to .005" [0,076 a 0,127 mm.] for number
two (2)
ring,
and side clearance of the oil
ring
should
be .0015" to .0085" [0,038 a
0,220
mm.].
To
check the end gap of a compression
ring,
place
it
in the cylinder in which it
will
be used, square
it
in the bore by tapping with the lower end of
a
piston, then measure the gap with a feeler
gauge.
A
compression
ring
should not have
less
than .015"
[0,381
mm.] gap when placed in cylinder
bore.
If gap is
less
than specified value, file the
end of the
ring
carefully with a fine file to obtain
proper
gap.
Dl-48.
Piston and Connecting Rod Assembly
Note:
A connecting rod can spring out of alignment
in
shipping or handling. Always check a new con
necting rod for misalignment before installing pis
ton and pin.
a.
If a new connecting rod is to be installed, check
its alignment with an accurate rod alignment fix
ture.
b.
If the piston and connecting rod assembly is
to be installed in the left cylinder bank, it must be assembled as shown in
Fig.
Dl-16. If the piston and
connecting rod assembly is to be installed in the
right
cylinder bank, it must be assembled as shown
in
Fig. Dl-17.
Note
that
these
two assemblies are
mirror-images
of each other.
c.
Lubricate
piston pin to avoid damage when
pressing
through the connecting rod.
d.
To install piston pin in piston and connecting
rod,
use
Tool
Set W-338.
Install
collar J-6047-5,
spring
J-6047-3, and pilot J-6047-20 into the base
support
J-6047-1 and place in
arbor
press. Using
driver
J-6047-4 press piston pin into piston and 88

DAUNTLESS
V-6
ENGINE
Note:
The rib on
edge
of cap and the conical
boss
on web of connecting rod must be toward
rear
of
engine
in all connecting rod assemblies of left
cyl
inder
bank and toward front of
engine
in all connecting rod assemblies of right cylinder bank.
Dl-50.
Oil
Pump Intake
and
Screen Cleaning
a.
Pry screen from housing and examine for clog
ging due to deposit of sludge or other foreign
material.
b.
Clean
the screen and housing thoroughly in sol
vent; dry with compressed air.
c.
Install
screen in housing.
Dl-51.
Oil Pan Cleaning and Inspection
Inspect
the oil pan for corrosion, dents, leaks, and
other damage. Inspect its mounting flange carefully
for damage or distortion to be certain that it
will
give
a
good
seal.
Dl-52.
Flywheel Cleaning
and
Inspection
Clean
the flywheel with suitable cleaning solvent;
dry
with compressed air. Inspect clutch face for
burned
or scuffed condition and for rivet grooves.
Inspection
for run out or improper mounting is de
scribed
in installation procedure.
Inspect
teeth
of the flywheel
ring
gear for
burrs,
nicks,
and minor distortion. If necessary and pos
sible, use a small emery wheel to remove
burrs
and
reshape teeth. If gear
teeth
are broken,
cracked,
seriously
burred
or deformed, the
ring
gear must be replaced.
Dl-53.
Ring Gear Replacement
a.
Drill
a
hole
between
two
ring
gear teeth; then
split
the gear with a cold chisel. Be careful not to
damage
ring
gear shoulder or seat surfaces of fly
wheel.
b.
Polish several
spots
on the new
ring
gear to be
installed.
With
a hot plate or slowly moving torch,
heat the new
ring
gear until polished
spots
become
blue, about
600°F.
[312°C.].
Caution:
Do not heat the
ring
gear to a temperature
greater than
800°F.
[424°C.].
Excessive heat
will
destroy heat treatment given to
ring
gear during
manufacture.
c.
Quickly
install
ring
gear on flywheel. Chamfered
edge
of
ring
gear must be toward
ring
gear shoulder
of flywheel. Be certain that
ring
gear is seated prop
erly.
Allow
ring
gear to cool slowly, so that it
will
be held tightly in place.
Dl-54.
Flywheel Housing Cleaning and Inspection
Both
flywheel and clutch are enclosed by a fly
wheel housing. Its front surface is bolted to the
engine
cylinder block, and its
rear
surface acts as
front
support to the transmission.
Clean
the fly wheel housing with a suitable cleaning solvent; dry
with
compressed air. Inspect front and
rear
surfaces
for distortion and improper alignment with each
other;
these
planes must be
parallel
to assure
proper
alignment
between
engine
and transmission.
Dl-55.
Camshaft Cleaning
and
Inspection
Clean
both camshaft and camshaft bearing surfaces
with
a suitable cleaning solvent; dry with com
pressed air.
Note:
The steel-backed babbitt-lined camshaft
bearings are pressed into the crankcase.
From
front
to
rear,
each bearing is .030" [0,76 mm.] smaller
in
diameter than the preceding bearing.
From
front
to
rear,
each camshaft
journal
is correspondingly
smaller
in diameter.
The
camshaft bearings must be line reamed to
proper
diameter after being pressed into crankcase.
Since
this operation requires special reaming equip
ment, the original bearings should be retained un
less
they are severly damaged. Slightly scored cam
shaft bearings are satisfactory if the surfaces of camshaft journals are polished, bearings are
polished to remove
burrs,
and
radial
clearance
between
camshaft and bearings is within .0015"
to .004" [0,038 a 0,102 mm.].
Dl-56.
Valve Lifter
and
Push
Rod
Cleaning and Inspection
a.
Examine the cam contact surface at lower end of each valve lifter body. If surface is excessively
worn,
galled, or otherwise damaged, discard the
valve lifter. Also examine the mating camshaft
lobe
for excessive wear or damage.
b.
Disassemble one or two valve lifters, as de
scribed
below, and inspect them for
dirt
or
varnish.
If
they are dirty or have a varnish deposit, clean
and
inspect all twelve valve lifters. Otherwise,
service
only
those
valve lifters which do not operate
properly.
c.
To disassemble each valve lifter, depress the
push
rod seat with a push rod, and remove the
plunger retainer from the valve lifter body with
a
retainer remover. Remove push rod seat and
plunger from valve lifter body. If plunger sticks
in
valve lifter body, place body in large end of
a
plunger remover tool, with plunger downward.
While
holding lifter with thumb, rap the open end
of remover against a block of wood with just enough force to jar the plunger from body. Refer to
Figs.
Dl-20, Dl-22 and Dl-23.
d.
Drain
oil from valve lifter and remove the check
valve retainer,
ball,
valve spring, and plunger
spring.
e. Keep all parts of each valve lifter separated
during
part cleaning and inspection. The valve
lifter
body and plunger are selectively fitted to each other and must not be interchanged with parts
of other valve lifters.
f. Rinse all valve lifter parts in kerosene to remove as much oil as possible.
This
will
reduce contamina
tion of the cleaning solvent. Immerse all parts in cleaning solvent for approximately one hour. The
time required
will
depend on varnish
deposits
and
effectiveness
of the solvent. After the varnish has
dissolved or has
softened
sufficiently to permit re
moval
by wiping, allow parts to
drain.
Varnish
can
then be cleaned from the valve lifter body
with
a
brush.
Rinse the parts in kerosene to dissolve 90

'Jeep'
UNIVERSAL
SERIES SERVICE
MANUAL
Dl
12712
FIG.
D1-20—REMOVING
PLUNGER
FROM
VALVE
LIFTER
BODY
1— Body 3—Support Tool
2—
Plunger
4—Wood Block the cleaning solvent. Wipe all parts, as necessary,
to dry them and remove any traces of varnish.
Note:
To promote cleanliness, it is advisable to
inspect and assemble each valve lifter before clean
ing the next valve lifter.
g. Inspect inner and outer surfaces of valve lifter
body for blow
holes
and scoring. Replace valve lifter assembly if body is roughly scored or grooved,
or
if it has a wall blow
hole
which would permit oil
leakage from lower chamber. The prominent wear
pattern just above lower end of body is not a
defect
unless it is definitely grooved or scored; it is caused
by side thrust of cam against body while the lifter
moves
vertically in its guide. A valve lifter body
which
has rotated in its guide
will
have a horizontal
wear
pattern, while a non-rotating body
will
have
a
square wear pattern with a very slight depression
near
the center. Inspect the cam contact surface on lower end of lifter body. Replace the valve lifter
assembly if this surface is excessively worn, galled
or
otherwise damaged.
Note:
Fig. Dl-21 illustrates the wear pattern of the
rotating and non-rotating valve lifters. The two
illustrations shown under B, "Normal Wear Pat
terns"
are the conditions encountered under general
use and replacement is not warranted unless the depth of the
groove
formed by the cam
lobe
is in
excess
of .020" [0,51 mm.] or the lifters do not
operate properly. The two illustrations shown under
A,
"Incorrect Wear Patterns" are normally accom panied by excessive wear or scoring of the respec
tive camshaft lobe.
This
type of wear is unsatis
factory and lifter replacement is necessary.
h.
Inspect outer surface of plunger for scratches
or
score marks.
Small
score marks with rough
satiny finish
will
cause the plunger to seize when 12751
FIG.
D1-21—HYDRAULIC
VALVE
LIFTER
WEAR PATTERNS
A—Incorrect
Wear Patterns B—Normal Wear Patterns
1—
Galled
and Pitted 3—Wear .020" Maximum
2— Soft 4—Rotating
5—Non-Rotating
hot but operate normally when cool. Using a magni
fying glass, inspect the check ball seat for defects.
Defects in check ball seat, or scores or scratches on
outer surface of plunger which can be felt with
a
fingernail, are reason to replace the valve lifter
assembly.
This
does
not apply to the slight
edge
which
may
sometimes
be present when the lower end of plunger
extends
below the ground inner
sur
face of the body.
This
edge
is not detrimental un
less
it is sharp or burred. A blackened appearance
is not necessarily a defective condition. Sometimes
such
a discoloration
gives
the outer surface of
plunger a ridged or fluted appearance. If the condi
tion
does
not cause improper operation, it may be
disregarded.
i.
Replace the push rod seat if the area contacted
by the push rod is rough or otherwise damaged.
Replace
any push rod which has a rough or dam
aged ball end.
j.
Using a magnifying glass, carefully examine the
check valve ball for nicks, imbedded material or
other
defects
which would prevent proper seating.
Such
defects
would cause intermittently noisy
operation.
Even
though no
defects
are found, it is
always advisable to discard the old ball and use
a
new one when reassembling the valve lifter,
k.
Examine check valve spring for wear or damage.
Replace
spring if it is distorted or shows evidence
of wear.
I.
Replace a check valve retainer if cracked or if
it
has heavily pounded area
between
the two holes.
A
small bright
spot
where the ball contacts the
retainer
is the normal condition.
m.
Replace the plunger spring only if it is distorted
or
damaged. Tests have shown the plunger springs
seldom break down in service.
n.
Rinse lifter plunger in kerosene. Hold plunger
in
vertical position with
feed
hole
upward, then 91

'Jeep'
UNIVERSAL
SERIES SERVICE
MANUAL
Dl Caution:
Oil ports of the rocker arm shaft must
coincide with oil return passages of the rocker
arms.
If they do not,
engine
oil has no return path
from
the cylinder head to the crankcase; in that
case,
engine
oil flows down the valve
stems
and
burns
in the cylinders.
There
is a notch at one end of each rocker arm shaft. When rocker arms
are
properly installed on the shaft, this notch
will
be at front of right rocker arm shaft and at
rear
of left rocker arm shaft. Refer to
Figs.
Dl-25 and
Dl-26.
a.
Position center support on rocker arm shaft;
insert
one shaft assembly attaching bolt through
support and shaft to hold support in position.
b.
Install
center
pair
of rocker arms with notched
faces touching support.
Install
front and
rear
spacer
FIG.
Dl-25—FRONT
OF RIGHT
ROCKER
ARM SHAFT
1—Alignment Notch
FIG.
Dl-26—REAR OF
LEFT
ROCKER
ARM SHAFT 2—Alignment Notch springs and one rocker arm each of front and
rear
rocker
arm pairs on shaft. Be certain that notched
faces of rocker arms are outward.
Install
outer shaft supports on shaft; compress spacer springs
to position supports. Insert one shaft assembly bolt
through each support and shaft to hold supports in
position.
c.
Install
remaining rocker arms of front and
rear
pairs,
each with notched face touching shaft sup
port.
Install
a spring retaining ring and flat washer at each end of shaft; secure each of
these
with a
new cotter pin.
D1 -61.
Valve Removal
a.
Place cylinder head on clean, smooth surface.
b.
Remove each valve assembly from cylinder
head as follows. Using suitable spring compressor, compress valve spring and remove two valve re
tainers
from valve stem. Release spring compressor,
and
remove spring retainer and valve spring from
valve stem. Refer to Fig. Dl-27.
Note:
Valve retainers are copper-colored for identi
fication purposes only.
c.
Withdraw valve from
bottom
of cylinder head.
Valves
should be identified so they can be installed
in
original location.
D1-62.
Cylinder
Head and Valve Cleaning
and
Inspection
a.
Remove carbon from combustion chamber of
cylinder
heads, using care to avoid scratching the head of valve seat surfaces. A
soft
wire brush is
suitable for this purpose.
b.
Clean
carbon and gum
deposits
from valve guide
bores with a standard-size valve guide reamer.
Refer
to Fig. Dl-28.
c.
Clean
valves with a wire
brush.
Inspect valve
faces and
seats
for pits, burned
spots
or other evi dence of poor seating.
FIG.
D1 -2 7—REMOVING
VALVE
RETAINERS
1—
Valve
Stem 3—Valve Spring Retainer
2—
Valve
Lock
4—Valve Spring
93

'Jeep*
UNIVERSAL
SERIES
SERVICE
MANUAL
Dl
Dl-65.
Rocker Arm Cover Cleaning
and Inspection
a.
Clean
both rocker arm covers with suitable
cleaning solvent and dry thoroughly.
b.
Inspect each rocker arm cover visually for
scratches,
bends, dents, and tears. Replace cover
if
unserviceable.
Dl-66.
Timing Chain
and
Sprocket Inspection
Inspect
the timing chain and both sprockets for
damage or excessive wear. Replace unserviceable
parts.
Dl-67.
Timing Chain Cover Cleaning and Inspection
a.
Clean
the timing chain cover with suitable clean
ing solvent and dry with compressed air.
b.
Inspect the cover visually for breaks,
cracks,
and
other damage.
With
a straightedge, check cylinder
block, water pump, and oil pump faces for bends
and
distortion.
c.
Install
oil pump gears in oil pump cavity of
timing gear cover.
With
a straightedge and feeler
gauge,
check gear and clearance. Refer to Fig.
Dl-30.
Clearance
should be
between
.0023"
[0,0584
mm.] and .0058"
[0,1358
mm.]. If it is lower
than
.0018" [0,0457 mm.], inspect thrust surfaces
of cover which touch gears for wear.
d.
Replace the timing chain cover if unserviceable.
FIG.
Dl-30—CHECKING
OIL
PUMP
GEAR
END
CLEARANCE
1—
Feeler
Gauge
2—
Straight
Edge
3—
Pump
Body
4—
Pump
Gears
Dl-63.
Oil Pump Cleaning and
Inspection
a.
Clean
gears with suitable cleaning solvent and
dry
thoroughly. Inspect for wear, scoring, and other damage. Replace either or both gears if unservice
able.
b.
Remove the oil pressure relief valve cap, spring
and
plunger. Refer to Fig. Dl-31. Oil filter bypass
valve plunger and spring are staked in place and should not be removed. 12719
FIG.
Dl-31—OIL
PUMP
PRESSURE
RELIEF
VALVE
1—
Valve
Cap
2—
Gasket
3—
Spring
4—Valve
5—
Oil
Pump
Cover
c.
Wash valve parts thoroughly. Inspect the relief
valve plunger for wear or scoring.
Check
the spring to see that it is not worn or collapsed. Replace any
relief
valve spring that is questionable. Thoroughly
clean
the screen staked in the cover.
d.
Insert the relief valve plunger into its bore in
the cover. The plunger should have no more clear ance than an easy slip fit. If there is any perceptible
sideways movement, the plunger and/or the cover should be replaced.
e.
Check
oil filter bypass valve plunger for
cracks,
nicks,
or warping. The plunger should be flat and free of nicks or scratches.
f.
Lubricate
and install pressure relief valve plung
er
and spring in bore of oil pump cover.
Install
cap and gasket. Torque cap to 30 to 40 lb-ft. [4,1 a 5,5 kg-m.]. Do not over-tig1 n.
Note:
Pressure relief valve cap has no tapped
hole
for installation of oil pressure switch.
H1
-69.
Crankshaft Vibration
Damper
Inspection
Inspect
the crankshaft vibration damper for
cracked,
broken, distorted, or otherwise damaged
condition. If damaged, replace.
Dl-70.
Crankshaft Pulley Inspection
Inspect
the crankshaft pulley for damage or exces
sive wear. Replace if visibly worn or damaged.
Dl-71.
ENGINE REASSEMBLY
The
engine
assembly procedure in the following
paragraphs
is given in the sequence to be followed
when the
engine
is being completely overhauled.
Individual
inspection,
repair,
and fitting operations
previously covered in detail are made throughout
the assembly procedure. The assembly procedure
does
not cover accessories. If a new cylinder block
fitted with pistons is used, many of the operations
will
not be required.
Mount
the cylinder block in an
engine
repair stand.
If
an
engine
stand is not available, perform the
following assembly operation in a manner designed to protect personnel against an accident, and the
engine
and its parts against damage. 95

Dl
DAUNTLESS
V-6
ENGINE
Note:
During
engine
reassembly, use Perfect Seal
Aerosol
Spray Sealer
Part
No.
994757
on all en
gine
gaskets to ensure against vacuum, oil, gasoline
and
water leaks. Apply to head gaskets, valve covers, water pumps, oil pan gaskets, radiator and
heater
hose
connections, felt gaskets, gasoline and
oil
line connections, stud bolts, spark plug threads,
and
grease retainer washers. Refer to manufac
turer's
instructions on container for proper appli
cation procedure.
Dl-72.
Cylinder
Block
and Crankshaft
Rear
Oil Seals
Braided
fabric seals are pressed into
grooves
of
cylinder
block and
rear
main bearing cap, to
rear
of the oil collecting groove, to seal against oil leak age at the crankshaft. Refer to Fig. Dl-32.
FIG.
Dl-32—INSTALLING
CRANKSHAFT REAR
OIL
SEAL
1—Neoprene
Seal
2—Fabric
Seal
A
neoprene composition (stick) seal is installed in
grooves
in the sides of the
rear
main bearing cap
to seal against leakage in the joints
between
the
cap and cylinder block. The neoprene composition
expands in the presence of oil and heat.
This
seal
is undersize when newly installed. Refer to Fig.
Dl-32.
a.
The braided fabric seal can be installed in the
cylinder
block only when the crankshaft is re moved; however, the seal in the cap can be replaced
whenever the cap is removed. Remove oil seal and place new seal in groove, with both ends projecting
above parting surface of cap. Force seal into
groove
by rubbing down with hammer handle or smooth
stick
until seal projects above the
groove
not more
than
[1,59 mm.]. Cut ends off flush with
sur
face of cap, using sharp knife or razor blade.
Lubricate
the seal with heavy
engine
oil just before
installation.
Caution:
The
engine
must be operated at slow
speed when first started after new braided seal
has been installed.
b. The neoprene composition seal is slightly longer
than
the
grooves
in the bearing cap. The seal must
not be cut to length. The seals are installed after the bearing cap is installed in the block and torqued
firmly
in place. Dip the neoprene seals in kerosene
approximately IV2 minutes, then install seals into
bearing cap grooves. The protruding ends of the seals are, again, squirted with kerosene, wiped off,
and
peaned over with a hammer to be sure of a
seal
at the upper parting line
between
the cap and
cylinder
block.
Dl-73.
Main
Bearing and Crankshaft
Installation
Refer
to Fig. Dl-6.
This
procedure assumes that crankshaft main bear
ings have been inspected and proven satisfactory,
or
that new crankshaft main bearings of appropriate size have been selected. If necessary, check or select
main
bearings as described in Par. Dl-41 and
Pars.
Dl-42 and Dl-43.
a.
Install
four upper main bearing halves in
seats
of cylinder block so that prong of each bearing half
fits into corresponding notch of seat. Flanged thrust
bearing must be installed in the second seat from
front of engine.
Install
a new upper crankshaft
rear
oil seal in the cylinder block as described in
Par.
Dl-72.
Caution:
Upper main bearing halves have an oil groove, while lower halves are plain. They must
not be interchanged.
b. Apply
engine
oil to upper bearing surfaces.
Install
the crankshaft so that its four journals rest
in
the upper bearing halves.
c. Seat all four lower main bearing halves in cor
responding bearing caps.
Install
a new lower
crank
shaft
rear
oil seal and cylinder block
rear
oil seal
described in
Par.
Dl-72, a and b.
Lubricate
all lower
main
bearing surfaces with
engine
oil. Position bear ing caps to cylinder block and crankcase journals.
Install
two cap bolts,
loosely,
at each cap.
d.
It is necessary to align thrust surfaces of the
second main bearing whenever it has been removed
from
the engine. To do this, pry the crankshaft
back
and forth several times, throughout its entire end travel, with cap
bolts
of second main bearing
only finger tight.
e. Tighten alternate cap
bolts
of each main bearing
cap,
a little at a time, until they have been tight ened to 80 to 110 lb-ft. [11,1 a 15,2 kg-m.] torque.
D1-74. Crankshaft End Play Check
To
measure crankshaft end play, mount a dial
indicator
on the cylinder block and index its plung
er
to either a front or
rear
face of one crankshaft
counterweight. Pry the crankshaft to one limit
of its end travel and adjust the dial indicator to
zero. Pry the crankshaft to its
opposite
end travel
limit
and
note
end play as indicated by the dial
indicator.
Crankshaft end play tolerances are .004"
to .008" [0,102 a
0,204
mm.]. If end play is too great, it can be corrected only by replacement of
the second main (thrust) bearing.
Dl-75.
Piston and Connecting Rod
Installation
This
procedure assumes that connecting rod bear ings have been inspected and proven satisfactory,
or
that new connecting rod bearings of appropriate 96

'Jeep'
UNIVERSAL
SERIES SERVICE
MANUAL
Dl
size have
been
selected. If necessary, check or
select
connecting rod bearings as described in Par. Dl-49.
Note:
When a piston and connecting rod assembly
is properly installed, the oil spurt
hole
in the con necting rod
will
face the camshaft. The rib on the
edge
of the bearing cap
will
be on the same side
as the conical
boss
on the connecting rod web;
these
marks (rib and boss)
will
be toward the other
connecting rod on the same crankpin. The notch
on the piston
will
face the front of the
engine.
a.
Be certain that cylinder bores, pistons, connect
ing rod bearings and crankshaft journals are absolutely clean. Coat all bearing surfaces with
engine
oil.
b. Before installing a piston and connecting rod as
sembly into its bore, rotate the crankshaft so that
the corresponding crankpin is moved downward, away from the cylinder bore.
c. Remove bearing cap from connecting rod. With
upper bearing half seated in connecting rod, install connecting rod guides. These
guides
hold the upper
bearing half in place and prevent damage to the
crankshaft
crankpin during installation of the con
necting rod and piston assembly.
d.
Be certain that the gap in the oil ring rails faces
upward,
toward center of
engine.
Gaps of the com
pression rings shall not be aligned with each other
or
with the oil ring
rails.
e. Lubricate the piston and rings. Compress the
rings with a suitable piston ring compressor; install
the piston and connecting rod assembly from top of cylinder bore. Refer to Fig. Dl-33.
f.
Install
bearing cap, with lower bearing half, on connecting rod. Torque bolt nuts to 30 to 40 lb-ft. [4,1 a 5,5 kg-m.].
g.
Install
all other piston and connecting rod as
semblies in same manner.
h.
Check
end clearance
between
connecting rods
on each crankpin with a feeler
gauge.
Clearance should be .005,/ to .012" [0,127 a
0,305
mm.].
Dl-76.
Install
Oil
Pump
Intake
Pipe
and
Screen Assembly
Check
mating surfaces of oil pump intake pipe
and
engine
cylinder block to be certain that they
are
clean. Secure the pipe and screen assembly,
with a new gasket, to
engine
cylinder block with two attaching screws. See Fig. Dl-34. Torque screws 6 to 9 lb-ft. [0,83 a 1,24 kg-m.].
Dl-77.
Install
Oil Pan
Refer
to Fig. Dl-35.
Be
certain the flange surface of oil pan and cor
responding surface of
engine
cylinder block are
clean.
Install
a new oil pan gasket on the cylinder
block.
Secure
oil pan to cylinder block with mount ing bolts. Torque
bolts
10 to 15 lb-ft [1,4 a 2,1
kg-m.].
Dl-78.
Install
Flywheel
Refer
to Fig. Dl-7.
a.
Check
flywheel flange of
engine
crankshaft and corresponding surface of flywheel to
be
certain that
FIG.
Dl-33—INSTALLING
PISTON
AND
CONNECTING
ROD
ASSEMBLY
1—Ring
Compressor
FIG.
Dl-34-^-OIL
PUMP
INTAKE PIPE
AND
SCREEN
INSTALLATION
1—Pipe and Screen
97