1953 JEEP DJ fuel pressure

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

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

'Jeep*
UNIVERSAL
SERIES
SERVICE
MANUAL

C

FIG.
C-2
7—FAN
BELT
—
DAUNTLESS
V-6
ENGINE
e. Adjust mixture by turning idle mixture screws
out (counterclockwise) until a loss of engine speed
is indicated; then, slowly
turn
both mixture screws

in
clockwise (leaner) until maximum speed (RPM)
is reached. Continue turning in (clockwise) until a slight drop in speed (RPM) is noted. Make certain
both mixture screws are adjusted equally.
This
will

ensure a "lean as possible" mixture adjustment.

Readjust
idle
stop
screw to idle engine at the
specified
R.P.M.

Note:
This
method of adjusting idle mixture must
be used to keep hydrocarbon and carbon monoxide
emissions to a minimum.

Note:
No fast idle speed adjustment is required.

Fast
idle is controlled by the curb idle speed ad­ justment screw. If the curb idle speed is correctly set, the fast idle speed
will
be correct.
C-26.
Dash
Pot
Adjustment

Refer
to Section
E, Par.
E-44 for proper carburetor

dash
pot adjustment procedure.

C-27.
Check
Fan
Belt

The
fan belt drives the fan, alternator, and water

pump.
See Fig. C-27.

Inspect
the fan belt for serviceability and proper
tension. The tension should be checked with the
Belt
Tension Gauge, W-283. The correct tension on a used belt is 70 to 80 pounds [31,7 a 36,2 kg.]

and
on a new belt 110 to 120 pounds [49,8 a 54,5 kg.]. When preparing for delivery of new car,
the belt strand tension should be 80 to 110 pounds [36,2 a 49,8 kg.]. When installing a new belt, adjust
the strand tension 110 to 120 pounds [49,8 a 54,5 kg.].

Adjust
the fan belt tension by loosening the clamp
bolt on the alternator brace and swinging the alter­

nator
away from the engine until proper belt ten­
sion is obtained.
Then
tighten the clamp bolt.

Note:
If no
gauge
is available approximate correct
tension is obtained when the thumb pressure mid­
way between the pulleys causes the belt to flex
y%
inch
[IV4
cm.].

C-28.
ROAD TEST VEHICLE

After
completing the tune-up, road
test
the vehicle for power and overall performance. Make neces­
sary
adjustments.

Note:
Engine run on or "dieseling" is a condition

in
which combustion continues to take place after
the normal ignition
spark
from the distributor has
been shut off by turning off the ignition switch. It is generally caused by excessive engine idle speed

in
combination with retarded ignition timing, en­ gine heat soak or the use of low octane fuel.

Should
engine dieseling (engine running after igni­
tion key is turned off) be experienced on V-6 engine equipped vehicles, installation of Idle Stop
Valve
Kit
Part
No. 991722
will
correct the

difficulty.
33

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