c
TUNE-UP
14011
FIG.
C-8—POSITIVE CRANKCASE VENTILATION VALVE
vacuum
hose
and insert a stiff wire into the valve
body and observe whether or not the plunger can be readily moved (Fig. C-8). The valve may be
cleaned, by soaking in a reliable carburetor clean
ing solution and drying with low pressure dry air.
b.
Hurricane
F4 Engine.
Ventilation
of the
Hurricane
F4
engine
is accom
plished in the same manner as the Dauntless V-6
engine
described above, the differences being that clean air enters the crankcase through a
hose
con nected
between
the top cover of the air cleaner and
the oil filler tube of the engine. The ventilation valve is screwed to a pipe fitting mounted in the
center of the intake manifold
between
number two
and
three cylinder inlet. A
hose
connects the venti
lation valve to a vapor
dome
on the rocker arm
cover. Service procedures are the same as
those
used on the Dauntless V-6 engine. The valve may be checked for vacuum
pull
by removing the
hose
from
the valve while running the
engine
at fast idle speed and placing a finger on the valve opening to
check the vacuum. (Refer to Fig. C-9).
C-7.
Service
Manifold
Heat
Control
Valve
The
Dauntless V-6
engine
is equipped with a manifold heat control valve (Fig. F-6). Test the valve
for free operation. Place a few drops of penetrating
oil
at each end of the shaft where it passes through
the manifold.
Then
move
the valve up and down
a
few times to work the oil into the bushing. When
the
engine
is cold, the valve should be in the closed
position to ensure a fast warm-up of the intake
manifold for better fuel vaporization. When the
valve is closed, the counterweight is in its counter clockwise position. As the
engine
warms the coun
terweight slowly rotates clockwise until the valve is fully open.
C-8.
Check
Valve
Tappet
Clearance
a.
Hurricane
F4 Engine.
With
the
engine
cold, check and adjust the intake
valve to .018"
[0,460
mm.] clearance and the ex
haust valves to .016" [0,406 mm.] clearance. The
intake valves are adjusted by removing the rocker
arm
cover mounted on the cylinder head.
Turn
the
engine
over until No. 1 cylinder piston is on top
dead center on its compression stroke, then using a
feeler
gauge
check the clearance
between
the valve stem and the toe of the rocker arm. If clearance is
less
or greater than .018"
[0,460
mm.] the valve
must be adjusted by turning the rocker arm nut
clockwise to decrease and counterclockwise to in crease the clearance. When No. 1 cylinder intake
valve has been properly set use the same proce
dures to check and reset, if necessary, the remaining
three cylinder valves. The exhaust valves are ad justed by removing the tappet cover located on
the right side of the engine. Place the cylinder to
be adjusted on top dead center (compression stroke) and check the clearance
between
the valve stem and tappet screw with a feeler
gauge.
If the
clearance is
less
or greater than .016" [0,406 mm.]
the valve must be adjusted by loosening the tappet
screw locknut and turning the screw until the proper clearance is obtained, then tighten the lock-
nut.
Note:
Always recheck the valve clearance after
tightening the locknut.
b. Dauntless V-6 Engine.
The
valve tappet clearance of the Dauntless V-6
engine
needs
no adjustment as the lifters are
hydraulic
and require no lash adjustment at time
of assembly or while in service.
C-9.
Check
Engine
Cylinder
Compression
a.
Hurricane
F4 Engine.
To
take the compression readings of the
engine
cylinders
remove all the
spark
plugs and disconnect
the high tension wire from the coil.
With
the throttle and choke open
turn
the
engine
with the
starter
motor while firmly holding the compression
gauge
in the
spark
plug port of the cylinder to be
checked. Allow at least four compression strokes
when checking each cylinder and record the first
and
fourth stroke reading of the
gauge.
When
pressure quickly
comes
up to specified pres
sure
and is uniform
between
all cylinders within 10 psi. [0,7 kg-cm2] it indicates that the
engine
is
operating normally with satisfactory seating of
rings,
valves, valve timing, etc.
When
pressure is low on the first stroke and builds
up to
less
than specified pressure it indicates com
pression leakage usually attributable to rings or
valves. To determine which is responsible, pour
Vz
oz. [15 cm3] of tune-up oil into each cylinder.
Allow
a few minutes for the oil to leak down past
the rings and then again
test
compression. If com
pression pressures improve over the first
test,
the trouble is probably worn piston rings and bores. If
compression pressures do not improve, the trouble
is probably caused by improper valve seating. If
this condition is noticed on only two cylinders that
are adjacent, it indicates that there is a possible gasket leak
between
these
cylinders. If inspection
of the
spark
plugs from
these
cylinders disclosed
fouling or surface cracking of electrodes, gasket leakage is probable.
When
pressure is higher than normal it indicates
that carbon
deposits
in the combustion chamber have reduced the side of the chamber enough to
give
the
effect
of a raised compression ratio.
This
will
usually cause a pinging sound in the
engine
when under load that cannot be satisfactorily corrected by timing. The carbon must be cleaned out
of the
engine
cylinders to correct this trouble.
Reinstall
the
spark
plugs. Torque with a wrench
to proper setting.
Advise
the vehicle owner if compression is not satisfactory. 24
c
TUNE-UP
meter during this
test
Connect the red lead
tc*
dis
tributor
primary
lead at the coil as shown in Fig.
C-21.
Connect black lead to the ground.
Turn
ignition switch on; with
engine
stopped, observe
dwell
meter. If the meter reads zero,
crank
the
engine
a fraction of a revolution to
close
the
breaker
points.
Distributor
resistance is normal, if dwell meter
pointer is within range of
black
bar. Distributor resistance is high, if
dwell
meter pointer is not
within
the black bar.
Remove test lead from
distri
butor terminal of coil and
connect
to
each
of the
following points to determine
where
the excessive resistance is:
Distributor
primary
terminal
Distributor
primary
terminal in the distributor
Breaker
point bracket
Ground
side of points
Distributor
housing
Where
a noticeable change occurs in the meter
reading
in
these
steps, make the necessary correc
tion and repeat the
test.
C-l 7. Distributor
Point
Dwell
Using
a dwell tester, connect red
lead
to the
distri
butor terminal at coil. Connect black lead to
ground.
Set selector switch to the number of
cylin
ders in the
engine
being tested. Operate
engine
speed at specified rpm. and
note
readings. Cam
dwell
angle must be 30° for the Dauntless V-6
Delco equipped engine, 29° ±: 3° Prestolite equipped
engine
and 42° for the
Hurricane
F4 engine. If the dwell reading is not to specifications,
trouble could be improper point spacing, point
rubbing,
defective block or breaker arm, or mis
aligned and worn distributor cam.
Adjust
dwell
as shown in Fig. C-14 for the Delco equipped
Dauntless V-6 engine. For cam dwell adjustment
of the Prestolite equipped V6 and
Hurricane
F4 engine, refer to Par. C-10,
step
a.
Dwell
variation is determined by noting any
dwell
change as the
engine
is operated at different
speeds.
Excessive
variation indicates a change in point opening that can result from shaft or bushing wear,
or
from the distributor plate shifting because of
wear
or
looseness.
Measure
dwell variation at idle speed, using same
test
hookup for checking dwell. Increase speed to 1750 rpm.;
note
dwell reading.
Then
slowly reduce
speed to idle while observing dwell meter. Dwell
variation
should not exceed 3°. If dwell variation
exceeds
3°
between
idle speed and 1750 rpm.,
probable wear in the distributor shaft, bushings, or
breaker
plate is indicated. Distributor should then be checked more thoroughly.
C-l8. Check Ignition Wires
and
Connections
Examine
and clean the insulation on all ignition
wires
and check all connections. Wires should be
firm,
flexible, and free from roughness and minute
cracks.
Bend wires to check for brittle,
cracked,
or
loose
insulation. Since defective insulation
will
per
mit
crossfiring or missing of the engine, defective
wires
should be replaced.
C-l9. Test Ignition
Cables
To
remove cables from
spark
plugs, use
Spark
Plug
Cable
Remover
Tool
W-274.
Twist
the
boot
slightly to break the seal and, grasping the rubber
protector
boot,
lift straight up with a steady even
pull.
Do not grasp the cable and
jerk
the cable off; this
will
damage the cables. Do not use a probe
on
these
wires; puncturing them may cause a
separation in the conductor. To remove ignition cables from the distributor cap or coil tower,
loosen
the nipple first, then grasp the upper part of the nipple and the cable and gently
pull
straight up.
Test
the cable with an ohmmeter. Resistance value
per
foot
is
3000-7000
ohms. The ignition cables
can
be checked for
circuit
continuity by removing
the cable from the
spark
plug and holding the cable
end Vi" [6,35 mm.] from the engine. A strong
spark
indicates
good
conductor continuity.
When
connecting the cable to the
spark
plug, be
certain
a
good
connection is made and that the
protector
boot
fits tight on the
spark
plug. A
partially
seated cable creates an additional gap in
the
circuit
and the resulting
spark
jump
will
cause
terminal
corrosion and cable damage.
C-20. Coil
When
an ignition coil is suspected of being defec tive, it should be checked on the car. A coil may
break
down after it has reached operating tempera
ture.
It is important that the coil be at operating
temperature when
tests
are made.
Note:
The ignition coil and ballast resistor for the
V-6
engine
must be of the same manufacturer.
Ballast
resistors and ignition coils of one manufac
turer
are interchangeable with both units of the
other.
C-21.
Service Air
Cleaner
Refer
to Par.
B-2 2
for the correct service of the
air
cleaner.
C-22.
Check Fuel Lines and
Screens
Check
all fuel line connections to guard against
leakage.
Check
fuel pump filter F4
engine
and
fuel
line filter V-6 engine. Replace fuel filter if
necessary.
C-23. Check Fuel Pump a.
Fuel
pump pressure is important, for low pres
sure
will
seriously affect
engine
operation and high
pressure
will
cause excessive fuel consumption and
possibly flood the carburetor. Should there be any doubt of normal operation, check the pressure with
a
gauge
as shown in Fig.
C-2 2.
The minimum and
maximum
allowable pressures are 2% to 3% lbs. [0,176 a
0,264
kg-cm2], for the
Hurricane
F4 en
gine.
Fuel
pump pressure at carburetor (inlet) on
the Dauntless V6-225
engine
should be 3% lbs.
[0,264
kg-cm2] minimum at specified
R.P.M.
idle
with
the vapor
return
hose
squeezed off.
With
the
vapor
return
hose
open pump pressure should be
2
V2
lbs. [0,176 kg-cm2] minimum.
b.
Test for volume, as a pump may build up suffi
cient pressure but
fail
to produce sufficient volume.
Turn
down the carburetor fuel line fitting on the
pump and with the tank line connected, pump out
30
'Jeep'
UNIVERSAL
SERIES
SERVICE
MANUAL
C
FIG.
C-22—-CHECKING
FUEL
PUMP
PRESSURE
—
DAUNTLESS
V-6
ENGINE a
couple of strokes to be sure the pump is primed.
Using
a half-pint
bottle
or similar measure, pump
Vi
pint [0,24 It] of fuel by cranking the
engine
with
the starter motor. Count the strokes neces
sary
to
fill
the measure. If more than 20 strokes
are
required, the fuel pump is inefficient, the tank
line is leaking air, or the fuel supply is restricted.
Check
fuel filter in the fuel tank if line is restricted.
C-24.
Check Manifold Vacuum
To
check the intake manifold vacuum on the
Hurri
cane F4 engine, remove the ventilation valve and
L
fitting from the manifold and install special adapter. On the Dauntless V-6
engine
remove the
pipe plug located in the right
rear
of the intake
FIG.
C-23—CHECKING MANIFOLD VACUUM
—
HURRICANE
F4
ENGINE
manifold and install special adapter. Connect the
vacuum
gauge
tube to the special adapter as shown
in
Fig. C-23 for the
Hurricane
F4 engine.
Start
the engine. Connect a Tachometer
Tool,
C-3896,
from the distributor
primary
terminal to ground and set the
engine
speed at the specified
rpm.
given in Par. C-30. Observe the vacuum
read
ing and interpret as follows:
a.
A steady reading from 18" to 20" [457 a 508
mm.] of mercury is a normal reading, indicating
that valve and
spark
timing, valve seating, and
piston ring sealing are all satisfactory.
b. A steady but below normal reading indicates
a
condition common to all cylinders such as a
leak
at the carburetor gasket, late ignition or valve
timing, or uniform piston ring and bore wear.
c.
A slowly fluctuating or drifting reading in dicates that the carburetor idle mixture is incorrect
Look
for the cause in the fuel system.
d.
A rhythmic pulsating reading is caused by a
condition affecting one or more cylinders, but not
all,
and indicates leaky valve, gasket blowby, re
stricted intake port, or an electrical miss.
e. An intermittent pulsating reading is caused by
an
occasional malfunction, such as a sticking valve
(all
valves may be
erratic
in operation if the valve
springs are weak), electrical miss caused by insuffi
cient distributor point tension or low coil
voltage
coupled with inconsistent
spark
plug
gaps
or fouled
plugs, or
dirt
in the fuel system finding its way into
passages of
critical
size or valve
seats
in the
car
buretor.
f.
A normal reading that quickly falls off (with
engine
running at
2000
rpm.) indicates exhaust
back
pressure caused by a restriction in the exhaust
system.
g.
Make indicated corrections to bring vacuum to 18" to 20" [457 a 508 mm.] of mercury normal
reading.
C-25.
Carburetor Adjustments
•
Refer to Fig. C-24, C-25 and C-26.
Carburetor
adjustments should not be attempted
until
it is known that
engine
ignition and com
pression are in
good
order. Any attempt to adjust
or
alter the carburetor to compensate for faulty conditions elsewhere
will
result in reduced econ
omy and overall performance.
Caution:
If an
engine
is idling too slow or rough,
this may be caused by a
clogged
ventilator valve
or
hose;
therefore, never adjust the carburetor idle
without first checking the crankcase ventilator
check valve and
hose.
The
air cleaner must be left in place while making
idle speed and mixture adjustments. All lights and accessories, must be turned off. The positive
crank
case ventilator system should also be in
good
oper
ating condition when making carburetor adjust ments.
Either
of
these
items noticeably affects the
air
fuel ratio at idle.
•
Hurricane
F4 Engine.
Note:
The idle mixture adjustment procedure for
the late model
YF-4941S
and
YF-6115S
Carter
31
c
TUNE-UP
Carburetor
equipped with the
External
Idle Mix
ture
Limiter
Cap is the same as outlined below
in
Pars.
"A"
through
"D";
however, because of the
Idle
Limiter
Cap,
the idle mixture screw
CANNOT
be adjusted in the counter-clockwise
(rich)
direc
tion. The adjustment is made from the
rich
stop
position and the mixture screw is turned in (clock
wise) approximately 3A turn to
"Lean
Best Idle."
Refer
to Fig. C-25.
The
"Lean
Best Idle" method of idle setting is as follows:
a.
Any scheduled service of ignition system should
precede this adjustment.
b.
Connect tachometer or vacuum
gauge
to engine.
c.
Warm
up
engine
and stabilize temperatures.
d.
Adjust
engine
idle to speed desired, using throt
tle idle speed adjusting screw.
e.
Carburetors without Idle
Limiter
Cap turn idle
mixture screws out (counterclockwise) until a
loss
of
engine
speed is indicated; then, slowly turn mix
ture screw in (clockwise-leaner) until maximum speed (RPM) is reached. Continue turning in (clockwise) until speed
begins
to drop; turn mix
ture adjustment back out (counterclockwise-richer)
until
maximum speed is just regained at a "lean as possible" mixture adjustment. Refer to
Fig.
C-24.
FIG.
C-24—CARBURETOR —
HURRICANE F4 ENGINE,
EARLY
MODEL 1—
Choke
Clamp Bracket
2—
Choke
Shaft and
Lever
Assembly
3—
Fuel
Inlet Elbow
4—
Bowl
Vent Tube 5— idle Air Adjusting
Needle
6—
Throttle
Lever
and Shalt Assembly
7—
Idle
Speed Adjusting Screw
8—
Fast
Idle Connector Rod
FIG.
C-25—CARBURETOR —
F4 ENGINE,
LATE
MODEL 1—
Choke
Clamp Bracket
2—
Throttle
Lever
and Shaft
3—
Choke
Shaft and
Lever
4 Bowl Vent Tube 5—
Fuel
Inlet Elbow 6—
Dash
Pot Bracket 7—
Throttle
Lever
8—
Dash
Pot Plunger
9—
Dash
Pot Assembly
10—
Lock
Nut
11— Stop Pin
12—
Idle
Mixture
Limiter
Cap 13—
Idle
Speed Adjusting Screw
14—
Fast
Idle Connecting Rod
Note:
When adjusting the mixture screw never
seat the screw tight during the adjustment proce
dure
as this can damage the screw needle.
•
Dauntless V-6 Engine.
The
"Lean
Best Idle" method of idle setting is
as follows:
a.
Any scheduled service of ignition system should
precede this adjustment.
b. Connect tachometer to engine.
c.
Warm
up
engine
and stablize temperatures.
d.
Adjust
engine
idle to speed desired, using throt
tle idle speed adjusting screw.
Note:
The
Carter
YF-6115S
Carburetor
has a throt
tle return spring attached from the carburetor
main
body to the carburetor throttle shaft The purpose of this spring is to return the throttle
to idle speed position should a linkage failure
occur.
FIG.
C-26—CARBURETOR —
DAUNTLESS V-6 ENGINE 1—
Fuel
Inlet
2—
-Choke
Housing
3—
Choke
Cable Bracket
4—
Idle
Speed Adjusting Screw
5—
Idle
Fuel-Air
Mixture Screws 32
'Jeep9
UNIVERSAL SERIES SERVICE
MANUAL
D HURRICANE
F4
ENGINE
Contents
SUBJECT
PAR.
GENERAL...
D-l Description D-2
Engine
Ground Strap D-4
Engine
Mountings D-3
ENGINE REMOVAL
D-5
ENGINE DISASSEMBLY
D-6
Camshaft
.......
D-28
Clutch
D-24
Crankshaft.
D-26
Crankshaft
Pulley. D-l2
Cylinder
Head. .D-17
Distributor.
.D-13
Exhaust
Manifold D-8
Exhaust
Valves and Springs D-2
7
Flywheel.
. D-25
Front
End Plate D-23
Oil
Filler
Tube D-9
Oil
Gallery Plugs D-30
Oil
Pan. . ...D-19
Oil
Pump D-l4
Piston and Connecting Rods. . . D-20
Ream
Cylinder Bore Ridges. D-l8
Rocker
Arm Assemblies D-l6 Thermostat D-ll
Timing
Gear
Cover . . D-21
Timing
Gears D-22
Valve
Tappets D-29
Ventilation Valve D-l5
Water
Outlet Fitting D-10
Water
Pump D-7
ENGINE INSPECTION
AND
REPAIR.
.D-31
Camshaft
and Bearings. D-51
Camshaft
End-Play
. . .D-53
Camshaft
Front Bearing Replacement..... D-52
Checking
Connecting Rod
Crank
Pins D-42
Checking
Crankshaft Alignment .
.
D-40
Checking
Main Bearing Journals. D-41
Cleaning.
. D-33 Connecting Rod Bearing Inspection D-48
Connecting Rod Bearings D-47 Connecting Rod Side Play D-50
Core
Hole Expansion Plug D-72
Crankshaft
.
.
D-38, 39
Crankshaft
Main Bearing Inspection D-44
Crankshaft
Main Bearings D-43
Crankshaft
Rear
Bearing Seal D-63
Cylinder
Block D-32
Cylinder
Bores D-35
Cylinder
Head. . . D-73
Exhaust
Valve Seat Insert Replacement. .
.
D-60
Fitting
Crankshaft Main Bearings
Using
Plastigage
D-45
Fitting
Crankshaft Main Bearings
Using
Shim Stock D-46
Floating
Oil Intake D-64
Flywheel.
. . .D-67
Flywheel
Housing D-71
SUBJECT
FAR.
Flywheel
Inspection. D-6 8
Flywheel
Pilot Bushing D-70 Inspection D-3 4
Inspection of Valves, Springs and Guides. .D-57
Installing
Connecting Rod Bearings....... D-49
Oil
Pan D-66
Oil
Pump D-65
Piston Ring Application
Chart
D-3 7
Pistons, Rings, and Connecting Rods..... D-36
Refacing
Valves
.
D-58
Ring
Gear
Replacement D-69
Rocker
Arm Shaft Disassembly. D-75, 76
Rocker
Arm Shaft Reassembly.
.
D-77
Rocker
Arms D-74
Tappets and Cover. . D-62
Timing
Gears and Cover D-54, 55
Valve
Guide Replacement D-61
Valve
Seat Inspection and Refacing D-59
Valve,
Springs and Guides D-56
ENGINE REASSEMBLY
D-78
Camshaft
and
Thrust
Plate .D-81
Camshaft
Timing
Gear
D-91
Check
Crankshaft
End-Play.
............D-83
Clutch.
...D-89
Crankshaft
and Bearings................ D-82
Crankshaft
Pulley D-96
Crankshaft
Rear
Bearing Seal.. .
.
D-85
Crankshaft
Timing
Gear
D-84
Cylinder
Head D-98
Distributor
D-l
00
Flywheel
®. . .. D-87
Flywheel
Housing D-88
Front
End Plate D-86
Manifold.......
D-101
Oil
Filler
Tube D-102
Oil
Gallery Plug. D-79
Oil
Pan. D-97
Oil
Pump D-93
Pistons and Connecting Rods D-95
Rocker
Arm Assembly D-99
Spark
Plugs. .D-100
Tappets D-80
Timing
Gear
Cover D-94
Timing
Gear
Oil Jet D-92
Valves
and Springs ... D-90
Water
Outlet Fitting D-104
Water
Pump D-103
ENGINE INSTALLATION.
............D-105
FINAL IN-VEHICLE
ADJUSTMENTS.
.D-106
Check
Valve Timing . . D-109
Crankcase
Ventilation Valve. D-l 10
Oil
Filter
, . .
...D-lll
Valve
Adjustment D-107
Valve
Adjustment Procedure D-l08
SERVICE
DIAGNOSIS
D-112
SPECIFICATIONS D-l
13 37
D
HURRICANE
F4
ENGINE
against the hub of the crankshaft pulley.
Timing
gears are accessible for inspection or replacement
with
the
engine
installed in the vehicle after re moving the radiator, belt drive pulley, and timing
cover.
Should
it be necessary to replace the timing gears, attention must be given to the end float of both
the camshaft and crankshaft and to the running
clearance
of both gears. It is also advisable to
check
both the oil jet and oil passage to the
crank
shaft front bearing to be sure that they are clear.
D-55.
Inspection and
Repair
Check
the general condition of both gears and
inspect for evidence of excessive wear. Replace
excessively worn or damaged gears. Inspect the
cover and replace if bent or damaged. It is recom mended that the crankshaft oil seal in the cover
be replaced when the cover is removed to ensure a
good
seal around the crankshaft. To replace this
seal
with the
engine
in the vehicle
requires
removing
the radiator and water pump.
D-56.
Valves, Springs, and Guides
The
exhaust valves seat on the top of the cylinder
block
with the
stems
extending down through
replaceable valve guides. The exhaust valves are actuated by the camshaft through exhaust valve
tappets. The exhaust valve springs are assembled
and
locked on the lower end of the exhaust valve
stems. The retaining locks are the split type, which
fit in a recess on the valve
stems
and into the taper
in
the valve spring retainers.
Adjustment
of exhaust valves is by means of the
adjusting
screw threaded into the upper end of the
exhaust valve tappets. An exhaust valve rotator used as a valve spring retainer is installed on the
lower end of the exhaust valve.
This
valve rotator,
known
as "Roto Cap", is a spring-loaded
ball
bearing
device. On each lift, or opening stroke of
a
valve, the rotator
gives
the valve a slight positive
clockwise rotation.
The
intake valves operate in valve
guides
in the
cylinder
head and are actuated by rocker arms.
The
rocker arms are actuated by valve push rods
and
the intake valve tappets. The intake valve
springs,
the intake valve spring retainers, and the
intake
valve spring retainer locks make up the
remainder
of the valve operating parts. An intake
valve spring retainer oil seal which encircles the
upper
end of the intake valve
between
the valve
locks and the upper end of the valve spring re
tainer,
controls the passage of oil along the valve
stem and guide.
Note:
When
engine
trouble indicates defective
valves as a possible source of trouble, also check
all
vacuum line connections for possible leaks.
D-57.
Inspection of Valves, Springs,
and
Guides
Clean
the valves on a wire wheel, making sure that
all
carbon is removed from the top and the under
side of the heads and that all gum and varnish
deposits
are removed from the stems.
Polish
the valve
stems
with steel wool or crocus
cloth.
Visually
inspect all valves for warpage,
cracks,
or excessive burning and discard if one of
these
conditions exists. Replace any worn, pitted,
or
corroded valves that cannot be cleaned with a
wire
brush.
Replace any valves when
seats
are pitted, burned, or corroded so badly that they
cannot be cleaned up with a light refacing on a valve refacing machine.
Replace
valves with marks of scoring or abrasion visible on the stem. Replace any valves with bent
stems
which
will
be apparent when the valve is
mounted in the valve refacing machine.
Note:
Use only hard-face exhaust valves for
replacement.
Examine
the
stems
of valves which employ the
ball
bearing rotators.
Wear
marks around the
cir
cumference of the
stems
indicates that the valve is
rotating satisfactorily.
Vertical
heavy pressure
areas
indicate that the valve is not rotating and the valve spring retainer (Roto
Cap)
should be replaced
if
at fault.
Check
the diameter of the valve stem at two or three places along the length of the stem
with
a micrometer. The intake valve stem diameter is .3733" to .3738" [9,482 a
9,495
mm.]. The
exhaust valve stem diameter is .371" to .372"
[9,423
a
9,449
mm.].
Note:
Exhaust
and intake valve springs are
similar
in appearance. They must not be inter
changed as they have different spring
charac
teristics.
Wash
the valve springs thoroughly in solvent.
Visually
examine the springs and replace any that
are
deformed or obviously damaged. Examine for
corrosion
from moisture or acid etching which might
FIG.
D-19—TESTING
VALVE
SPRING
1—
Torque
Wrench
2—
Spring
Testing
Fixture
3—
Valve
Spring
54
D
HURRICANE
F4
ENGINE
D-101.
Install
Manifold
If
manifold studs were removed for replacement,
apply sealer on the stud threads
before
installing
a
new stud.
See Section Fl for exhaust emission controlled
engines.
Make
certain that no foreign objects are inside the manifold and that all
passages
are clear. Place a
new set of manifold
gaskets
in position on the side
of the cylinder block.
Then,
carefully slide the manifold
onto
the studs and against the cylinder block being careful not to damage the gaskets.
Torque
all manifold attaching nuts evenly 29 to
35 lb-ft. [4,0 a 4,8 kg-m.].
D-102.
Install
Oil
Filler
Tube
When
installing the oil filler tube, be sure that the
beveled lower end is away from the crankshaft.
Place a
piece
of
hard
wood
over the top of the
tube
to prevent damage to the cap gasket seat.
D-103.
Install
Water Pump
Make
certain that the mating surfaces of the water pump and the cylinder block are clean and smooth.
Install
the gasket on the
flange
of the pump and
install
the pump in position on the cylinder block.
Torque
the water pump attaching
bolts
alternately
and
evenly 12 to 17 lb-ft. [1,7 a 2,3 kg-m.].
D-104.
Install
Water Outlet Fitting
Install
the thermostat and the water
outlet
fitting.
Torque
the water
outlet
fitting attaching
bolts
20
to 25 lb-ft. [2,8 a 3,4 kg-m.].
FIG.
D-42—INSTALLING HURRICANE F4 ENGINE
IN
VEHICLE
1—
Lifting
Sling
2— Hoist
Cable
3—
Hurricane
F4 Engine
4— Dowel Bolt
5—
Flywheel
Housing
D-105.
ENGINE INSTALLATION
a.
Install
lifting sling to
engine
and using suitable hoist raise the
engine
from its blocking or stand
and
then slowly lower it
into
the
engine
compartment of the vehicle.
Note:
When installing the
Hurricane
F4 Engine,
two % x 4 inch
guide
bolts
or
dowels
should be
used to properly
guide
and align the
engine
to the
flywheel housing (See Fig. D-42).
b. Slightly tilt the
engine
downward and at the
same time slide the
engine
rearward
while lining up the transmission main gear shaft with the clutch
throw-out bearing and disc spline.
Note
:The
engine
crankshaft may have to be turned
slightly to align the transmission main gear shaft
with the clutch disc spline.
c. Remove the
guide
bolts
or
dowels
and secure
the
engine
to the housing.
d.
Secure the front
engine
mounts to the frame brackets and
bolt
ground cable to
engine.
e. Remove lifting sling from
engine.
f. Connect exhaust pipe to
engine
manifold flange.
g. Connect throttle and choke cables to carburetor.
h.
Install
fan to water pump pulley.
i.
Connect fuel pump line to main fuel line,
j.
Replace starting motor assembly. k. Connect
engine
wiring harness connectors at
front of cowl.
I.
Connect wires to starting motor assembly, water
temperature and oil pressure sending units and alternator.
NOTE:
ON
ENGINES EQUIPPED WITH EX
HAUST
EMISSION CONTROL,
REPLACE
THE
AIR
PUMP,
AIR
DISTRIBUTOR
MANI
FOLD,
AND
ANTI-BACKFIRE (DIVERTER)
VALVE.
SEE
SECTION
Fl.
m. Replace radiator and radiator grille support
rods and connect coolant
hoses
to
engine.
Note:
Replace heater
hoses
if vehicle is equipped
with hot water heater.
n. Fill
radiator with coolant and
engine
with oil
(see
Lubrication
Chart).
o.
Install
air cleaner and connect carburetor air
hose.
p. Connect battery cables and start
engine,
q.
Install
hood
and road
test
vehicle.
D-103.
FINAL
IN-VEHICLE
ADJUSTMENTS
a.
Clean
battery terminals and check battery. b.
Check
ignition terminals and check battery.
c. Service carburetor air cleaner.
d.
Service positive crankcase ventilation valve.
e.
Check
fuel lines. f. Gap and install new
spark
plugs.
g.
Check
distributor
points
and capacitor; replace
if
necessary. 68
'Jeep9
UNIVERSAL
SERIES
SERVICE
MANUAL
h.
Check
ignition (distributor) timing; reset if
necessary.
i.
Check
carburetor
adjustments; reset if necessary,
j.
With
engine
fully warmed up, tighten cylinder
head and manifold
bolts
and nuts to specified
torque.
Check
cylinder head gaskets and
bolts
for
air
or coolant leaks.
Note:
Tightness of cylinder head
bolts
should be
checked and corrected after 500 to 600 miles [800
a
960 km.] of normal operation.
k.
Check
fan belt tension; adjust if necessary.
I.
Check
for and correct any oil leak, fuel leak or
coolant leak.
D-107.
VALVE
ADJUSTMENT
Proper
valve adjustment is important to prevent
burning
of valves and poor
engine
performance.
This
adjustment consists of obtaining a specified
lash
in the valve mechanism. The exhaust valve
tappets and the intake valve rocker arms should be adjusted to the proper clearance with the
engine
cold (at room temperature). Valve clearance can
be properly adjusted only when the tappet is on the
heel or low portion of the cam.
INTAKE
OPENS
9°
BTC?
FIG.
D-43-
10270
-VALVE
TIMING
D-108. Valve Adjustment Procedure
The
exhaust valve tappets are adjusted by turning
the adjusting screw in or out of the tappet as neces
sary
to obtain the proper clearance. Where special
wrenches can be obtained, they should be used to facilitate the adjustment. The proper clearance is .016" [0,406 mm.]
between
the end of the adjusting
screw and the
bottom
of the exhaust valve.
Crank
the
engine
over to
close
a valve and check
the clearance with a feeler
gauge.
To adjust, hold
the tappet with one wrench and
turn
the adjusting
screw,
with the other.
Check
and adjust each of
the tappets in proper sequence.
Adjust
each intake valve by adjusting the rocker
arm
screw at the push rod to obtain .018" [0,457 mm.] clearance
between
the rocker arm and the
valve stem with tappet on the heel of the cam.
D-109.
Check
Valve
Timing
To
check the valve timing, carefully set the intake
valve rocker arm adjustment for No. 1 cylinder to .026"
[0,6604
mm.]
between
the rocker arm and the
valve stem. Rotate the crankshaft clockwise until
the piston in No. 1 cylinder is ready for the intake stroke. The intake valve
opens
9° before top center
(BTC).
Note
the distance
between
the
"TC"
and
"5°"
marks on the indicator on the timing gear
cover and estimate the 9° before top center position.
See
Fig.
D-43.
With
the crankshaft in this position, timing is correct if the rocker arm is just tight
against the intake valve stem. Do not overlook resetting the rocker arm adjustment to the correct
running
clearance.
D-110. Positive
Crankcase
Ventilation
Be
sure there are no air leaks at the tube connec
tions
between
the air cleaner and the oil filler tube,
and
that the oil filler tube cap gasket is in
good
condition. Always keep the cap locked securely in
place. When tuning the
engine
or grinding valves, remove the control valve and clean it thoroughly.
If
the valve is blocked with carbon, the ventilating
system
will
not operate and, should the valve
fail
to seat, it
will
be impossible to make the
engine
idle satisfactorily. Refer to Par. C-6 for servicing.
D-111. Oil
Filter
The
engine
is equipped with a throw-away type
oil
filter.
This
oil filter must be serviced periodi
cally
as outlined in the
Lubrication
Section. 69