fuel cap JEEP CJ 1953 Service Manual

GENERAL
DATA
A-8. GENERAL SPECIFICATIONS

MODEL:
CJ-3B
CJ-5,
CJ-5A
DJ-5
CJ-6,
CJ-6A
DJ-6

Engine:.
Number
of
Cylinders

Bore.
.

Stroke.
Displacement
Compression
Ratio:
Late
Production —
Standard
—
Optional.
—
Optional.

Early
Production —
Standard

—
Optional.

—
Optional.

Compression
Pressure

Horsepower
(max.
Brake)
Horsepower
(SAE)

Torque
(Max. at 2000
rpm.).
. . .

Engine:
Number
of
Cylinders

Bore

Stroke

Displacement

Compression
Ratio

Horsepower
(max.
Brake).
Horsepower
(SAE)

Torque
(Max. at 2400
rpm.).
. . .

Wheelbase

Tread
(front and
rear)
,

Height
(Over
all)
Length
(Over
all).

Width
(Over
all)

Ground
Clearance
F-4

4
3.125 [7,93 cm.]
4.375 [11,11 cm.]
134.2 cu. in. [2,20 ltr.]
7.4:1 7.8:1
6.9:1
120 to 130 psi.
[8,4 a 9,2 kg-cm2] 75 <§ 4000 rpm.
15.63
114 lb-ft. [15,8 kg-m.]

80"
[2,03 m.]
487-'f6/' [1,23 m.|
6634" [1,68 m.j

129%"
[3,30 m.]
68%"
[1,75 m.] 8" [20,32 cm.]
F-4

4
3.125 [7,93 cm.]
4.375 [11,11 cm.]
134.2 cu. in. [2,20 ltr.]
6.7:1 7.1:1
6.3:1 7.4:1
7.8:1
6.9:1
120 to 130 psi.
[8,4 a 9,2 kg-cm2] 75 @ 4000 rpm. 15.63
114 lb-ft. [15,8 kg-m.]

V-6
6
3.750" [9,525 cm.]
3.400" [8,636 cm.]
225 cu.
in.
[3,69 ltr.] 9.0:1
160 @ 4200 rpm. 33.748
235 lb-ft. [32,49 kg-m.]
81"
[2,06 m.]

48K6"
[1,23 m.]

67"
[1,70 m.]

138%"
[3,51 m.]
71%"
[1,82 m.] 8" [20,32 cm.]
F-4

4
3,125 [7.93 cm.]
4.375 [11,11 cm.]
134.2 cu. in. [2,20 ltr.]
6.7:1 7.1:1
6.3:1 7.4:1
7.8:1
6.9:1
120 to 130 psi.
[8,4 a 9,2 kg-cm2] 75 @ 4000 rpm.
15.63
114 lb-ft. [15,8 kg-m.]

V-6
6
3.750" [9,525 cm.]
3.400" [8,636 cm.]
225 cu. in. [3,69 ltr.] 9.0:1
160 @, 4200 rpm. 33 748
235 lb-ft. [32,49 kg-m.]
101"
[2,57 m.]
48^6* ]1,23 m.]

67"
[1,70 m.]
1583/4" [4,02 m.]
71%"
[1,82 m.] 8" [20,32 cm.]

CAPACITIES:
U.S.

Imperial
Metric

Fuel
Tank
(Approximate):
Early
Models

Late
Models

Cooling
System

F4
Models

V-6
Models
Note: If not equipped
with
heater deduct 10.5 gal.
16 gal.
12 qt.
10 qt.
1 qt. 8.8 gal.
13.3 gal.
10 qt. 8 qt.
.8 qt. 39,75 ltr.
60,57 ltr.
11,4 ltr. 9,5 ltr.
0,9 ltr.

CJ-
3B

CJ-5
CJ-6
DJ-5

DJ
-6

lb. kg. lb.
kg. lb.
kg. lb.
kg. lb.
kg.

WEIGHTS
(Approximate):
Gross
Vehicle
Weight
(GVW).
3500
1587 3750 1701 3900 1769 3200 1451 3200 1451

Shipping
— V6
Engine
—
'—
2240 1016 2302 1044 1900 862 2033 922

F4
Engine
2132
967 2163
981 2225
1009 1796 814 1858 842

Curb
— V6
Engine
— —

2351 1066 2413 1094 2011 912 2144 972

F4
Engine
2243
1017 2274 1031
2336 1060 1907 865 1969 893

For
Canvas
Half-Top
Model, add 35
17 38
17 38
17 38
17 38 17

For
Canvas
Full-Top
Model, add 56
25 56 25 60 27 56 25 60 27

For
Hard
Top Model, add
~~
340
154 340 154 6

'Jeep*
UNIVERSAL
SERIES
SERVICE
MANUAL

13330

FIG.
B-4—ENGINE
LUBRICATION
SYSTEM
—
DAUNTLESS
V-6
ENGINE

1—
Rocker
Arm Shaft
2—
Main
Oil
Line

3—
Oil
Inlet where it is connected by a drilled passage in the

cylinder
crankcase to an oil screen housing and
pipe assembly. The screen is submerged in the oil supply and has ample area for all operating condi­
tions. If the screen should
become
clogged
for any reason, oil may be drawn into the system over the
top
edge
of the screen, which is held clear of the

sheet
metal screen housing.

Oil
is drawn into the pump through the screen and
pipe assembly and a drilled passage in the
crank­

case, which connects to drilled passages in the
timing chain cover. All oil is discharged from the
pump to the oil pump cover assembly. The cover
assembly consists of an oil pressure relief valve,
an
oil filter bypass valve and a nipple for installa­
tion of an oil filter. The spring loaded oil pressure

relief
valve limits the oil pressure to a maximum
of 30 pounds [13.607 kg.] per square inch. The

oil
filter bypass valve
opens
when the filter has
become
clogged
to the
extent
that
4V2
to 5 pounds [2.04 a 2.27 kg.] pressure difference exists
between

the filter inlet and exhaust to bypass the oil filter
and
channel unfiltered oil directly to the main oil galleries of the engine.

A
full flow oil filter is externally mounted to the

oil
filter cover nipple on the right side of the en­ gine, just below the alternator. Normally, all
engine

oil
passes through the filter element; however, if
the element
becomes
restricted, a spring loaded bypass valve
opens
as mentioned above. The main

oil
galleries run the full length of the crankcase
and
cut into the valve lifter guide
holes
to supply

oil
at full pressure to the lifters. Connecting pas­
sages
drilled in the crankcase permit delivery of

oil
at full pressure to all crankshaft and camshaft
bearings.
Holes drilled in the crankshaft
carry
oil from the
crankshaft
bearings to the connecting rod bearings.
Pistons and cylinder walls are lubricated by oil
forced through a small notch in the bearing parting
surface on the connecting rod, which registers with
the
hole
in the crankpin
once
in every revolution. Piston pins are lubricated by splash.

Drilled
holes
in the camshaft connect the front camshaft bearing
journal
to the key slot in the front
of the camshaft. Oil flows from the
journal
into
the keyslot over the woodruff key in the space

between
the key and the camshaft sprocket and fuel pump eccentric.

The
forward end of the fuel pump eccentric in­ corporates a relief which allows the oil to escape

between
the fuel pump eccentric and the camshaft

distributor
gear. The oil stream strikes the distri­
butor shaft gear
once
each camshaft revolution, and provides ample lubrication of the timing chain and
sprockets by splash.

The
rocker arms and valves on each cylinder head

are
supplied with oil from the oil galleries through

holes
drilled in the front of the cylinder block and

cylinder
head. The
hole
drilled in the cylinder
head ends beneath the front rocker
arm
shaft brack­ et. A notch cast in the base of the rocker arm shaft

bracket
allows the oil to flow up inside the bracket

in
the space
between
the bracket and bolt, to the
hollow rocker arm shaft which is plugged at both
ends.
Each
rocker arm receives oil through a
hole

in
the underside of the shaft. Grooves in the rocker

arm
provide lubrication of the bearing surface. Oil
is metered to the push rod seat and valve stem
through
holes
drilled in the rocker arm. Excess
oil
drains off and returns to the oil pan through
passages in the cylinder head and block. Refer to
the
Lubrication
Chart
for lubrication frequency and

lubrication
type and grade.

B-7.
Chassis
Lubrication

Chassis
and
engine
should be serviced at periodic
intervals.
Most chassis lubricating points, whether
long-life or conventional, have standard lubrication
fittings. Refer to the
Lubrication
Specifications and

Service
Maintenance Schedule for specific points

and
lubricating time intervals. It is not necessary
to disassemble prepacked joints to lubricate them.

Merely
add new lubricant, as described in Par.
B-3,
to remove all old lubricant.

At
the appropriate interval, clean each lubrication
fitting indicated on the Lubrication
Chart
and
Service
Maintenance Schedule. Use a pressure gun
to lubricate. Be sure the grease channels are open
to provide complete lubrication of bearing surfaces.
In
some
cases it may be necessary to disassemble
to clear plugged channels.

When
vehicles are driven primarily in abnormally dusty or wet areas or when a vehicle is subject to
severe operating conditions, perform
these
services
more frequently. Under
these
conditions, no definite interval can be recommended because of the great variety of
uses
and conditions of use. 11

'Jeep'
UNIVERSAL
SERIES SERVICE
MANUAL

B
e.
Check
for the presence of
excess
water in the

oil
that might indicate an internal leak from the
cooling system.

f.
Pour oil into the oil filler tube. Replace the oil

filler
cap.

B-10.
Engine Oil
Filter
Service —
Hurricane
F4 Engine

The
engine
oil filter assembly should be replaced at each
2000
miles
[3.200
km.] of normal
engine

use. To remove the filter, use oil filter wrench
C-4065.
To install a new filter, wipe the gasket —
contact surface with
engine
oil, screw on the unit

until
gasket contacts the sealing surface, and then tighten at least one
half
turn
more. DO NOT USE

TOOLS.
Turn
by hand only. When refilling the
engine
crankcase after filter has been changed be

sure
to add one extra quart [1 ltr.] of oil to
fill

filter
and oil passages. Run
engine
to make sure there is no leak at oil filter.

B-l 1.
Engine Oil
Filter
Service — Dauntless V-6 Engine

To
replace the oil filter, use oil filter wrench, Tool

C-4065,
to remove the filter. After the filter has
been removed from the oil pump housing located
on the right front side of the engine, wipe the
housing surface clean and oil the gasket on the base of the new filter to make a
good
seal. Screw
the new filter in position until its gasket contacts
the pump housing surface, then tighten at least
one-half
turn
until filter fits snug.

Note:
Tighten by hand only, do not use a tool to
tighten.

Replace
oil filter each
6000
miles
[9.600
km.] at

engine
oil change.

B-12.
Exhaust
Manifold
Heat
Control
Valve
— Dauntless V-6 Engine

A
thermally-actuated heat control valve is located at
rear
of the right exhaust manifold of the Daunt­

less
V-6 engine.
This
valve has a bimetal thermo­
static spring which holds the valve closed when
the
engine
is cold.

Each
time the vehicle is lubricated place a few drops of penetrating oil on the valve shaft bushings

and
then work the valve by hand making sure that
the lubricant is worked into the bushings.

Note:
If the valve shaft
does
not operate freely
penetrating oil should be used to free the shaft.

B-l 3.
Positive
Crankcase
Ventilation
System

Service
the ventilation system of the
engine
each
multiple of
6000
miles
[9.600
km.] on the odometer
after
initial
2000
miles
[3.200
km.] service. Re­
place the ventilation valve each
12,000
miles
[19.200
km.].

For
information on servicing the positive crankcase
ventilation system on the
Hurricane
F4
engine
and
the Dauntless V-6 engine, refer to the Tune-up Section.

B-l4.
Distributor
— Hurricane F4 Engine

The
distributor shaft is lubricated through an oiler mounted on the side of the housing. Place three or four drops of light
engine
oil in the oiler each
2,000

miles
[3.200
km.]. Also place one drop of light
engine
oil on the wick located on the top of the
shaft, which is made accessible by removing the
rotor
arm. Sparingly apply cam lubricant to the
breaker
arm cam and place a drop of oil on the

breaker
arm pivot.

B-l
5.
Distributor
— Dauntless V-6 Engine

The
distributor has a lubricant reservoir that
car­

ries
sufficient
lubricant
for the life of the distributor.
When
servicing breaker points, place one drop of
light
engine
oil on the wick located on the top of the shaft Also, apply cam lubricant sparingly to
the breaker arm cam, and place a drop of oil on the

breaker
arm pivot.

B-l6.
Generator

On
early production vehicles oilers are provided
at each end of the generator, for lubrication
pur­

pose.
On late production vehicles one oiler is pro­
vided at the
rear
(bushing end) of the generator for lubrication purpose. Place two to four drops of
light
engine
oil in each oiler every
2,000
miles
[3.200
km.].

B-l
7. Spark Plugs

Replace
spark
plugs. Refer to Section C.

B-18.
Starting
Circuit

Check
the starting
circuit.
Refer to Section H.

B-l
9. Charging
Circuit

Check
the charging
circuit.
Refer to Section H.

B-20.
Engine Tune-Up

Refer
to Section C of this manual.

B-21.
Adjust
Fan
Belt

Refer
to Section C.

B-22.
Exhaust Emission
Control
System or
Controlled
Combustion System

•
Refer to the appropriate section in this manual.

B-23.
Exhaust System

Check
the exhaust system for leaks. Refer to Section F.

B-24.
Fuel Evaporative Emission
Control
Canister Air
Filter

The
only service required for the
F.E.E.C.
system
is cleaning the air cleaner filter mounted at the
bottom
of the canister. The filter requires replace­
ment at
12,000
mile intervals. Refer to Section

E,
Par. E-9 for service procedure.

B-25.
Oil Bath Air Cleaner
Some 'Jeep' Universal vehicles are equipped with

an
oil bath type air cleaner.
This
type air cleaner
thoroughly removes all dust from the air before it enters the carburetor, if it is properly serviced.

When
the vehicle is operated under normal condi­
tions the air cleaner must be serviced at regular

intervals
as care of the air cleaner is extremely 13

Jeep*
UNIVERSAL SERIES SERVICE
MANUAL

c
TUNE-UP

Contents

SUBJECT
PAR.

GENERAL
C-l

TUNE-UP
.C-2
Air
Cleaner
C-21

Battery
. C-3
Carburetor
Adjustments
C-2 5

Coil
C-20
Crankcase
Ventilation C-6

Cylinder
Compression C-9

Cylinder
Head(s) .C-5

Dash
Pot Adjustments .C-26

Distributor
Service C-10
thru
C-13

Distributor
Resistance Test C-l6

Fan
Belt
C-2 7
Fuel
Lines
and Screens
C-2
2

C-l.
GENERAL
An
engine tune-up should be performed for all
Jeep Vehicles each 6000 miles [9.600 km.] or at the end of each 250 hours off-the-road operation,
to ensure best possible performance at all times.
The
tune-up should follow the sequence given in
this section.
Because of federal laws limiting exhaust emissions,

it
is even more important that the engine tune-up is
done
accurately, using the specifications listed
on the tune-up sticker found in each engine com­

partment.

Note;
To ensure proper operation and effectiveness
of the exhaust emission control system, and to
comply with
Federal
and State requirements, a
recheck
of ignition timing, idle speed and idle mix­

ture
and necessary adjustments must be performed
after the first
2,000
miles [3.200 km.] of vehicle
operation.

A
minor engine tune-up should be performed every
6,000
miles [9.600 km.] or at the end of 250 hours
of off-the-road use.
Major
engine tune-up should
be performed every 12,000 miles [19.300 km.].

The
parts of units which affect power and perform­
ance may be divided into three groups:
(1) Units affecting compression
(2) Units affecting ignition
(3) Units affecting carburetion

The
tune-up procedure should cover
these
groups
in
the order given. While the items affecting com­
pression and ignition may be handled according
to personal preference, correction of items in the
carburetion
group should not be attempted until

all
items affecting compression and ignition have
been satisfactorily corrected.

Note:
To make sure hydro-carbon and carbon
monoxide emissions
will
be within limits, it is very

impotrant
that the adjustments be followed exactly
as listed on the sticker found in each engine compartment.
SUBJECT
PAR.

Fuel
Pump . . C-23

Heat
Control
Valve C-7

Ignition
Cables C-19

Ignition
Timing
. C-14

Ignition
Wires C-l8

Manifold
C-5

Manifold
Vacuum C-24

Point
Dwell C-17

Primary
Circuit
Tests
.................
C-15
Spark
Plugs C-4

Tappets
C-8

ROAD TEST C-2
8

SERVICE
DIAGNOSIS
. : C-29

TUNE-UP SPECIFICATIONS..
C-30

Minor
engine tune-up consists of the following.
Inspect
and correct as required:
Battery
cables and connections.
Alternator
and regulator wiring.

Primary
— Secondary wiring, distributor cap.

Cylinder
head torque.

Contact
point dwell.

Vacuum
and centrifugal advance.

Ignition
timing.
Spark
plugs for correct air gap.

Adjust
idle speed and idle air mixture.

Adjust
all drive belt tensions.
Clean
carburetor air cleaner.

Lubricate
exhaust manifold damper.

Major
engine tune-up includes the following.
Inspect
and correct as required:
Battery
condition and charging
circuit.
Clean,
lubricate
and tighten battery cable connec­
tions.

Ingition
system.
Spark
plugs; replace if necessary or clean and gap.

Compression
check.

Primary—Secondary
wiring, distributor cap.

Replace
contact points and condenser.

Lubricate
distributor cam with cam grease.
Adjust
contact points.

Check
vacuum and centrifugal advance. Set ignition timing.

Torque
cylinder head.
Adjust
idle speed and idle air mixture.

Replace
fuel filter element (every 12,000 miles [19.300
km.]).

Adjust
all drive belt tensions.

IMPORTANT: SPECIFICATIONS
FOR EN-

GINE
RPM.
DISTRIBUTOR POINT DWELL,
AND IGNITION TIMING GIVEN
IN
TUNE- UP SECTION
C
REFER
TO
VEHICLES
WITH
AND WITHOUT EXHAUST EMISSION CON­

TROL
SYSTEMS.

FOR
VEHICLES
EQUIPPED WITH EXHAUST
EMISSION CONTROL SYSTEMS ALSO
REFER
TO
SECTION
Fl (F4-134
ENGINE)
AND
F2 (V6-225
ENGINE).
19

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

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

TUNE-UP

C-29.
SERVICE
DIAGNOSIS

POOR
FUEL ECONOMY Ignition Timing Slow or Spark Advance Stuck

Carburetor
Float High
Accelerator Pump Not Properly Adjusted High Fuel Pump Pressure

Fuel
Leakage

Leaky
Fuel Pump Diaphragm Loose Engine Mounting Causing High Fuel Level in Carburetor

Low
Compression
Valves Sticking
Spark
Plugs Bad

Spark
Plug Cables Bad
Weak
Coil
or Condenser Improper Valve Tappet Clearance

Carburetor
Air Cleaner Dirty
High Oil Level in Air Cleaner Dragging Brakes

Front
Wheels Out of Alignment

Tires
Improperly Inflated Inaccurate Odometer

Faulty
Fuel Tank Cap
Clogged
Muffler or Bent Exhaust Pipe Sticking Exhaust Manifold Valve

LACK
OF POWER
Low
Compression Ignition System (Timing Late)
Improper Functioning Carburetor
or Fuel Pump

Fuel
Lines
Clogged

Air
Cleaner Restricted Engine Temperature High Improper Tappet Clearance
Sticking Valves
Valve Timing Late

Leaky
Gaskets
Muffler
Clogged

Bent Exhaust Pipe Sticking Exhaust Manifold Valve —
Dauntless V-6 Engine

LOW
COMPRESSION
Leaky
Valves Poor Piston Ring Seal Sticking Valves
Valve Spring Weak or Broken
Cylinder
Scored or Worn
Tappet Clearance Incorrect Piston Clearance too Large

Leaky
Cylinder Head Gasket

BURNED
VALVES AND SEATS Sticking Valves or too Loose in Guides
Improper Timing
Excessive Carbon Around Valve Head and Seat Overheating
Valve Spring Weak or Broken
Valve Tappet Sticking
Valve Tappet Clearance Incorrect
Clogged
Exhaust System

Defective
Valve
Lifter
— Hydraulic
VALVES
STICKING
Warped Valve Improper Tappet Clearance Carbonized or Scored Valve
Stems

Insufficient Clearance Valve Stem to Guide
Weak or Broken Valve Spring Valve Spring Cocked Contaminated Oil

OVERHEATING
Inoperative Cooling System
Theromstat Inoperative Improper Ignition Timing
Improper Valve Timing
Excessive Carbon Accumulation
Fan
Belt too Loose

Clogged
Muffler or Bent Exhaust Pipe
Oil
System Failure Scored or Leaky Piston Rings
Sticking Exhaust Manifold Valve — Dauntless V-6 Engine

POPPING-SPITTING-DETONATION
Improper Ignition Improper Carburetion
Excessive Carbon
Deposit
in
Combustion Chambers
Poor Valve Seating Sticking Valves
Broken Valve Spring Tappets Adjusted too Close
Spark
Plug Electrodes Burned
Water or Dirt in Fuel
Clogged
Lines Improper Valve Timing

Clogged
Fuel Filter Sticking Exhaust Manifold Valve —
Dauntless V-6 Engine

EXCESSIVE
OIL CONSUMPTION Piston Rings Stuck in Grooves, Worn or Broken Piston Rings Improperly Fitted or Weak Piston Ring Oil Return
Holes
Clogged

Excessive Clearance, Main and
Connecting Rod Bearings

Oil
Leaks at Gaskets or Oil Seals
Excessive Clearance, Valve Stem
to Valve Guide (Intake)

Cylinder
Bores Scored, Out-of-
Round or Tapered
Too Much Clearance, Piston to Cylinder Bore
Misaligned Connecting Rods
High Road
Speeds
or Temperature
Crankcase
Ventilator Not Operating

BEARING
FAILURE
Crankshaft
Bearing Journal Out-of-Round

Crankshaft
Bearing Journal Rough

Lack
of Oil
Oil
Leakage

Dirty
Oil

Low
Oil Pressure or Oil Pump Failure

Drilled
Passages
in Crankcase or Crankshaft
Clogged

Oil
Screen Dirty
Connecting Rod Bent 34

HURRICANE
F4
ENGINE

D-1.
GENERAL

This
section describes service and repair of the
F4
engine. The
engine
code
number shown in Fig.
A-3
is provided to identify the four cylinder engine.
The
meaning of the coded letters and numbers that

are
stamped on the water pump boss, at the front of the cylinder block, is given below.
Letter
to
Designate
Market

M
—
Military
E
—
Export

D
— Domestic
I
—
Industrial
&
Marine

Letter
to
Designate
Engine
Letter
to
Designate
Year
Built
R
— 1969

S
— 1970

T
— 1971
U—
1972

V
— 1973

W
— 1974

Numbers
to Designate
Compression
Ratio

F
— F4-134
Engine
63
67
•

71
-
6.3 to 1

•
6.7 to 1

-
7.1 to 1

Market
-
D
S F

(Domestic)

(1970)

Engine-
EXAMPLE

123 A B S
(F4-134)

Day- "L

Compression
Ratio

(6.7)
-
Service Engine (S)
Short
Block
(R)

-.010*
Oversize Pistons

(123rd)
-.010*
Undersize
Main

and
Rod Bearings
All
disassembly and assembly procedures are
presented in logical order, assuming a complete

engine
overhaul with
engine
removed from the vehicle. However, many of
these
procedures can
also be performed as on-vehicle services if vehicle
or
engine
components are removed to gain access
to parts involved.

Note:
Some
engines
are equipped with an exhaust
emission control system. Service information on
the components of this system is given in Section

F-l.
D-2.
Description

The
Hurricane
F4-134
engine
is an F-head, four-
cyiinder
engine
of combination valve-in-head and valve-in-block construction.
Large
intake valves
mounted in the head allow
rapid,
unobstructed
flow of fuel and air to the combustion chambers through short, water-jacketed intake passages.The
intake valves are operated by push rods through

rocker
arms. The exhaust valves are mounted

in
the block with through water jacketing to provide
effective
cooling. The exhaust valves are
operated by conventional valve tappets.
The
engine
is pressure lubricated. An oil pump

driven
from the camshaft forces the lubricant
through oil channels and drilled passages in the

crankshaft
to efficiently lubricate the main and
connecting rod bearings.
Lubricant
is also force
fed to the camshaft bearings, rocker arms, timing
gears, etc.
Cylinder
walls and piston pins are

lubricated
from spurt
holes
in the "follow" side of
the connecting rods.
Circulation
of the coolant is controlled by a
thermostat in the water
outlet
elbow cast as part
of the cylinder head.

The
cylinder head assembly when installed on the

engine
consists of the inlet valve guides, inlet valves, inlet valve springs, rocker arm and shaft assemblies, spark plugs, temperature indicator
fitting, water
outlet
fitting, and other assembled

parts.
The carburetor and air cleaner assembly
bolt to the top of the cylinder head. The rocker

arm
cover is attached to the top of the head to
enclose
the inlet valve mechanism.
The
engine
is equipped with a fully counterbalanced
crankshaft
supported by three main bearings. To better control balance, the counterweights are in­
dependently forged and permanently attached to
the crankshaft with dowels and cap screws that are tack-welded.
Crankshaft
end play is adjusted by
shims placed
between
the crankshaft thrust washer

and
the shoulder on the crankshaft.
The
exhaust manifold is a separate unit. The intake
manifold is cast as an integral part of the cylinder
head and is completely water jacketed.
This
con­
struction transfers heat from the cooling system
to the intake passages and assists in vaporizing
the fuel when the
engine
is cold. Therefore, there
is no heat control valve required in the exhaust manifold. Individual exhaust ports in the cylinder
block direct
gasses
into the exhaust manifold for unobstructed flow through the exhaust system.

The
pistons have an extra
groove
directly above
the top ring which acts as a heat dam or insulator.
As
is common practice with manufacturers,
some

engines
are built with oversize cylinder bores or undersize crankshaft journals. These
engines
are
considered standard as replacement parts of the

correct
sizes are supplied. Before ordering parts or
doing any work with a particular engine, it is important to check the
engine
code
number to
determine if oversize or undersize parts are re­

quired.
Definite identification is given by a letter
stamped after the
engine
code
number. See Fig.

A-5
for location. The letters used and their mean­ ings are given here:

A
— .010*
[0,254
mm.] undersize main and
connecting rod bearings.

B
— .010"
[0,254
mm.] oversize pistons.

AB
—
Combination
of A and B.

S
—
Service
engine.

R
—
Short
Block.
Detailed specifications for the
Hurricane
F4
engine

are
at the end of this section.
Torque
specifications
for
engine
service are at the end of this manual in Section U. When adjustments are necessary, refer to
these
specifications so that factory clearances

are
maintained.

D-3.
Engine Mountings

The
front of the
engine
is supported by two rubber
Text continued on
page
41. 38

'Jeep'
UNIVERSAL
SERIES
SERVICE
MANUAL

D
satisfactory bearing replacement cannot be made

and
it
will
be necessary to regrind the crankshaft.

Install
the bearing lower
half
and the connecting

rod
cap and draw the cap bolt nuts down equally
and
only slightly tight. Move the connecting rod
endwise, one way or the other, on the crankshaft to be sure the bearing is not tight.
Pull
the nuts tighter, first one then the other, a little at a time,

and
keep trying the fit of the rod on the crankshaft by hand until the recommended torque of 35 to 45 lb-ft. [4,8 a 6,2 kg-m.] is reached. If the
bearings are of the correct size, and have been
properly
lubricated with light
engine
oil before in­

stallation,
the connecting rod should be easy to
slide back and forth parallel to the
crankpin.
If
the connecting rod is tight on the crankshaft, a

larger
bearing is required. If there is no binding

or
tightness, it is
still
necessary to check clearance
to guard against too
loose
a fit. The use of "Plasti­

gage"
or shim stock of the proper size to measure .001" [0,025 mm.] clearance is recommended for

checking
connecting rod bearing clearances.
This

is the same material recommended for checking
crankshaft
main bearings and the method of check­
ing is
similar.
Refer to
Par.
D-45 or D-46. Connect­
ing rod bearings are fitted to the same clearance as the main bearings but the torque specified for con­
necting rod cap
bolts
is different.

D-50.
Connecting
Rod
Side Play

Check
the connecting rod side play with a feeler
gauge
as shown in Fig. D-l8. The side clearance is .004" to .010"
[0,101
a
0,254
mm.].

D-51.
Camshaft and Bearings

The
camshaft is supported at four points in the

cylinder
block. The front is supported in a re­ placeable, steel-shell, babbit-lined bearing. The

bearing
is pressed into place The other three bear-
FIG.
D-18—CONNECTING
ROD
SIDE
PLAY
ing surfaces are precision machined in the cylinder
block. The camshaft bearings are pressure
lubri­

cated through drilled passages in the crankcase.

End
thrust of the camshaft is taken by a thrust plate bolted to the crankcase. The camshaft is

driven
by a silent helical-cut
tooth
timing gear at
the front of the engine. A worm gear, integral with
the camshaft, drives the oil pump and distributor.

The
fuel pump is actuated by an eccentric forged

onto
the camshaft.

Clean
the camshaft thoroughly in cleaning solvent.
Inspect
all camshaft bearing surfaces to determine

if
they are scored or rough. The cam faces must be
perfectly smooth throughout their contact face

and
must not be scored or worn.

D-52.
Camshaft
Front Bearing Replacement

Use
a suitable driver to remove the camshaft front
bearing
from the cylinder block. To install a new
bearing,
align the oil
hole
in the bearing with the
bored oil
hole
in the cylinder block and drive the

bearing
in until the front end of the bearing is

flush
with the front surface of the cylinder block.

Make
sure the oil
hole
is open and clear. It is not
necessary to line-ream the bearing after installation because bearings for replacement are precision
reamed
to the finished size. Do not stake the

bearing.

D-53-
Camshaft End Play

End
play of the camshaft is determined by running
clearance
between
the
rear
face of the camshaft gear and the thrust plate and is established by the

spacer
thickness. The standard clearance is .004"
to .007"
[0,101
a 0,178 mm.] and can be measured by a
dial
indicator. As a general rule this clearance

will
change but little through wear or when a new gear is installed. To predetermine the correct end
float with the gear, spacer, and thrust plate re­
moved, measure the thickness of both the thrust
plate and spacer with a micrometer. The thickness
of the spacer should be approximately .006" [0,152 mm.] greater than that of the thrust plate.

When
this is correct and the parts are assembled

and
drawn tightly
together
by the gear retaining

screw,
the end play should
come
within standard
limits.

D-54.
Timing Gears
and
Cover

The
timing gears are mounted at the front of the
engine. Camshaft drive is through helical-cut
timing gears; a steel gear on the crankshaft and a
pressed fiber gear on the camshaft. The gears are keyed to their respective shafts. The camshaft

driven
gear is secured on the front end of the
camshaft by means of a capscrew and a plain

washer.
The crankshaft gear is secured on the
front end of the crankshaft by a nut threaded
onto
the front end of the crankshaft holding the
crank­

shaft pulley, crankshaft oil slinger, and the
crank­

shaft drive gear spacer. The timing gears are

lubricated
through a jet threaded into the
crank­
case directly above the gear contact and oil supplied
through a drilled passage from the front main

bearing.
The timing gears are enclosed by the
sealed timing cover. The oil seal in the cover bears 53

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