JEEP CJ 1953 Owner's Manual

'Jeep'
UNIVERSAL SERIES SERVICE
MANUAL

FIG.
C-3—SETTING SPARK PLUG
GAP
1—Wire
Gauge 2—Spark Plug
c.
Blow out all carbon and
dirt
from each
spark

plug hole with compressed air. If compressed air is
not available, start the engine and accelerate to 1000 rpm. to blow out the carbon and
dirt.
Stop
the engine.

d.
Remove the plugs carefully with a
spark
plug

wrench.

e. Inspect the plugs for serviceability. Especially
check
for burned and eroded electrodes, blistering
of porcelain at the firing tip, cracked porcelain, or

black
deposits and fouling. These conditions in­
dicate that the plugs have not been operating at
the correct temperature. Replace bad or worn plugs

in
sets.
f. Measure the electrode gap of each new or exist­
ing plug with a wire
gauge
as shown in Fig. C-3.

Adjust
each electrode gap to the specific gap by
bending the outer electrode mounted in the plug
shell.

g.
Clean
the plugs on a sand blast cleaner. Avoid
too much abrasive blast as it
will
erode the in­
sulator.
Clean
the threads with a wire
brush.

Deposits
will
retard
heat flow to the cylinder head.

h.
Clean
the electrode surfaces with a small flat
file. Dress the electrodes to secure flat parallel surfaces on both the center and side electrode.

i.
Champion J-8 are the replacement
spark
plugs
recommended for the F4-134 engine. Adjust elec­
trode gap to .030" [0,762 mm.] and should be
torqued to 25 to 33 lb-ft. [3,5 a 4,6 kg-m.].

j.
For the V6-225 engine, AC 44S or Champion

UJ12Y
spark
plugs are the replacement
spark

plugs recommended. The
spark
plugs should be gapped to .035" [0,889 mm.] and should be
torqued to 25 to 33 lb-ft. [3,5 a 4,6 kg-m.].
C-5. Torque Cylinder
Head(s)
and
Manifold
a.
Hurricane
F4 Engine.

Torque
the cylinder head bolts with a torque

wrench
to 60 to 70 lb-ft [8,3 a 9,7 kg-m.]. Follow
the sequence shown in Fig. C-4. Do not overlook
tightening the cylinder head bolt, No. 5, in the

intake
manifold directly under the carburetor
opening. 10102

FIG.
C-4—HURRICANE
F4
ENGINE CYLINDER HEAD BOLT TIGHTENING SEQUENCE
Torque
all manifold attaching nuts evenly to 29
to 33 lb-ft. [4,0 a 4,6 kg-m.].
b.
Dauntless V-6 Engine.

Torque
cylinder head bolts 65 to 85 lb-ft. [9,0 a 11,8 kg-m.]. Follow the sequence shown in Fig.

C-5.
Torque all intake manifold bolts 45 to 55 lb-ft. [6,2 a 7,6 kg-m.]. Torque all exhaust manifold bolts
15 to 20 lb-ft. [2,1 a 2,8 kg-m.]. Refer to Fig. Dl-
for tightening sequence. 14203

FIG.
C-5—DAUNTLESS
V-6
ENGINE CYLINDER HEAD BOLT TIGHTENING SEQUENCE C-6.
Service
Crankcase
Ventilating System

•
Refer to Fig. C-6 and C-7.
Positive crankcase ventilation is accomplished by

utilizing
the vacuum created in the intake mani­
fold to draw clean air through the crankcase and
valve chamber. A valve, in the vacuum line to the

intake
manifold, varies the air flow through the

crankcase
to
meet
changing conditions at all engine

speeds
and loads. The system
will
work effectively as long as all component parts are clean and free

from
sludge and carbon. Improper operation of the ventilating system can contribute to rough
idling,
power loss, and the formation of sludge and

varnish
in the engine.

The
system also prevents crankcase vapors from
entering the atmosphere. Engine vapors are drawn
into the carburetor through the ventilation valve
and
burned with the normal fuel mixture. 21

c

TUNE-UP
I

FIG.
C-6—CRANKCASE VENTILATION
VALVE
SYSTEM, V6 ENGINE

1—
Hose
Clamp
2— Hose, Breather to Air Cleaner
3— Grommet, Valve1 Cover

4—
Crankcase
Ventilation Valve 5— Hose. Valve to Carburetor
.
...-.X
;

urn

FIG.
C-7—POSITIVE
CRANKCASE VENTILATION
VALVE
LOCATION —- DAUNTLESS V-6 ENGINE

1—Hose
on Engines with
Fuel
Evaporization
Emission
Control System Only 22

'Jeep'
UNIVERSAL SERIES SERVICE
MANUAL

C The
valve, connecting pipes, and
hoses
must be
inspected and serviced at intervals of
2,000
[3.200

km.],
6,000
[9.600 km.] and 12,000 [19.300 km.]
miles, continuing each
6,000
miles [9.600 km.] of
vehicle operation thereafter. It may be necessary to inspect and clean the system more frequently

under
adverse driving or weather conditions.
Replace
the valve each 12,000 miles [19.300 km.],

a.
Dauntless V-6 Engine.

Filtered
air from the carburetor air cleaner enters the engine crankcase through a hose. The ventila­tion valve is mounted on the right cylinder bank
rocker
arm cover (Fig. C-7) and is connected by a

hose
to a fitting at the base of the carburetor at the

intake
manifold opening. The valve varies the air
flow through the crankcase to
meet
changing condi­
tions at all engine
speeds
and loads. To check the operation of the system, remove the valve with the

hose
attached from the rocker arm cover.
With
the engine running at fast idle, a vacuum must be felt
at the open end of the ventilation valve. If no

vacuum
is present, the valve and
hose
should be
inspected and cause of the restriction determined.

To
check the valve disconnect it from the air
13334

FIG.
C-9—POSITIVE CRANKCASE VENTILATION SYSTEM
— F4
ENGINE (TYPICAL)
1—Valve
Open 2—Valve Closed
23

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

'Jeep*
UNIVERSAL SERIES SERVICE
MANUAL

COMPRESSION PRESSURE LIMIT CHART

Maximum
Pressure
Minimum

Pressure
Maximum

Pressure
Minimum

Pressure

psi.
kg-cm2
psi.
kg-cm2
psi.

kg-cm2

psi.

kg-cm2

134 9,42 101 7,10
188
13,22 141
9,91
136 9,56 102 7,17 190
13,36 142
9,98
138 9,70 104 7,31 192
13,50 144 10,12
140 9,84 105 7,38 194
13,64 145
10,19
142 9,98 107 7,52 196
13,78 147 10,33
144 10,12 108 7,59 198
13,92
148 10,40
146 10,26 110 7,73 200
14,06 150 10,55
148 10,40 111 7,80
202
14,20 151
10,62
150 10,55 113 7,94 204
14,34 153
10,76
152 10,68 114 8,01 206
14,48 154 10,83
154 10,83
115 8,08 208
14,62 156
10,97
156 10,97 117 8,23
210
14,76 157 11,04
158 11,11 118 8,30 212
14,90
158 11,11
160 11,25 120
8,44 214
15,04 160
11,25
162 11,39 121 8,51 216
15,18 162 11,39
164 11,53
123 8,65 218
15,32 163
11,46
166 11,67 124 8,72 220
15,46 165 11,60
168 11,81 126 8,86 222
15,61 166
11,67
170 11,95 127 9,83 224
15,75 168 11,81
172 12,09 129 9,07 226
15,89 169
11,88
174 12,23 131 9,21 228
16,03 171 12,02
176 12,37 132 9,28 230
16,17 172
12,09
178 12,51 133 9,35 232
16,31
174 12,23
180 12,65 135 9,49
234
16,45 175 12,30
182 12,79 136 9,56 236
16,59 177 12,44
184 12,94 138 9,70
238
16,73 178 12,51
186 13,08 140 9,84
b.
Dauntless V-6 Engine.

To
check the
engine
cylinder compression use the
following procedures:

Firmly
insert compression
gauge
in
spark
plug
port
(Fig.
C-10).
Crank
engine
through at least four
compression strokes to obtain highest possible

reading.

Check
compression of each cylinder. Repeat com­
pression check and record highest reading obtained on each cylinder during the two pressure checks.

Note:
The recorded compression pressures are to
be considered normal if the lowest reading cylinder
is more than seventy-five percent of the highest

reading
cylinder. See the following example and
the "Compression Pressure
Limit
Chart".
Example:

Cylinder
No. 1 2 3 4 5 6

Pressure
(psi.) 129 135 140 121 120 100
Seventy-five percent of 140 (highest) is 105.
Thus,

Cylinder
No. 6 is
less
than seventy-five percent
of
Cylinder
No. 3.
This
condition, accompanied by low speed missing, indicates an improperly seated
valve or worn or broken piston
ring.

If
one or more cylinders read low, inject about

a
tablespoon of
engine
oil on top of pistons in low

reading
cylinders through
spark
plug port. Repeat compression check on
these
cylinders.

If
compression improves considerably, rings are

worn.
If compression
does
not improve, valves are

sticking
or seating poorly.

If
two adjacent cylinders indicate low compression

and
injecting oil
does
not increase compression, the
cause may be a head gasket leak
between
the

cylinders.
Engine coolant and/or oil in cylinders could result from this
defect.
FIG.
C-10—CHECKING ENGINE CYLINDER
COMPRESSION
—
DAUNTLESS
V-6
ENGINE
FIG.
C-l
1—CONTACT
POINTS
MATERIAL
TRANSFER

25

c

TUNE-UP
C-10.
Distributor
Service

The
distributor cap should be inspected for
cracks,

carbon runners and evidence of arcing. If any
of
these
conditions exists, the cap should be re­
placed.
Clean
any corroded high tension terminals. Inspect the rotor for cracks or evidence of
exces­

sive burning at the end of the metal strip. After

a
distributor rotor has had normal use the end
of the rotor
will
become
burned. If burning is found
on top of the rotor it indicates the rotor is too
short and
needs
replacing. Usually when this con­
dition is found the distributor cap
segment
will

be burned on the horizontal face and the cap
will

also need replacing.
Check
the condenser lead for broken wires or

frayed
insulation.
Clean
and tighten the connec­
tions
on the terminal
posts.
Be sure the condenser
is mounted firmly on the distributor for a
good
ground connection. Should a condenser tester be available the capacity
should be checked. In the absence of a tester check
by substituting a new condenser.
Examine
the distributor
points
(Fig.
C-ll).
If
they

show wear, poor mating, transferred metal, or pitting, then new
ones
should be installed.
Clean

the
points
with a suitable solvent and a stiff
bristled brush.
Check
the alignment of the point for a
full,
square
contact. If not correctly aligned, bend the station­
ary
contact bracket slightly to provide alignment,

a.
Hurricane F4 Engine (Prestolite).

The
contact gap of the distributor point on the

Hurricane
F4
engine
should be set at .020"
[0,508

mm.],
measured with a wire
gauge.
Adjustment of
the gap is accomplished by
loosening
the lock screw and turning adjusting eccentric screw (Fig.
C-12)
until correct gap is secured. Be sure that the
fiber block on the breaker arm is resting on the
highest point on the cam while the adjustment is being made. Recheck the gap after locking the
adjustment.

Apply
a thin film of cam lubricant to the cam to
lessen fiber block wear. Should a condenser tester be available the capacity
should check from .21 to .25 microfarads. In the
absence of a tester check by substituting a new
condenser.

Check
point contact spring pressure, which should
be
between
17 and 20
ounces
[0,487
a 0,56 kg.].
Check
with a spring scale hooked on the breaker

arm
at the contact and pull at right
angle
to the

breaker
arm. Make the reading just as the
points

separate. Adjust the point pressure by
loosening
the stud holding the end of the contact arm spring

and
slide the end of the spring in or out as neces­

sary.
Retighten the stud and recheck the pressure. Too low a pressure
will
cause
engine
missing at
high
speeds.
Too high a pressure
will
cause rapid wear of the cam, block, and points.
b. Dauntless V-6 Engine (Delco).

The
spark advance is fully automatic being con­
trolled by built-in centrifugal weights, and by a vacuum advance system (Fig.
C-13).
The same
checking procedures are used as (a)
above
except,

the capacity of the condenser must be .18 to .23 microfarads and the contact gap should be set at
.016"
[0,406
mm.]. Adjustment of the gap is made
by rotating the socket head adjustment screw with
a
Vs" [3,86 mm.] Allen wrench (Fig.
C-14).

The
contact spring pressure must be 19 to 23 ozs.
[0,538
a
0,652
gr.] and the cam dwell
angle
is

30°,
with distributor vacuum line disconnected.
The
preferred method of adjusting cam dwell re­
quires turning of the adjusting screw until the specific dwell
angle
is obtained as measured by a
dwell
angle
meter. Refer to Par. C-l7. To adjust
the cam dwell by an alternate method, turn the adjusting screw in (clockwise) until the
engine

FIG.
C-12—PRESTOLITE DISTRIBUTOR HURRICANE F4 ENGINE
1— Condenser
2—
Lubricating
Wick

3—
Breaker
Cam
4—
Breaker
Arm Pivot 5—
Distributor
Cap (Rotation &
Firing
Order)
6—
Distributor
Points 7— Adjustment
Lock
Screw
8—
Adjusting
Eccentric
Screw
9—
Oiler

10—Primary
Wire
26

'Jeep*
UNIVERSAL
SERIES SERVICE
MANUAL

C
12763

FIG
C-13—
DELCO
DISTRIBUTOR —
DAUNTLESS V-6 ENGINE
1—
Rotor
8—Access Passage

2—
Breaker
Plate Assembly 9—Shaft Bushing
3—
Lubrication
Reservoir 10—Vacuum Assembly
4—
Primary
Terminal
11—Cam
5—
Distributor
Housing 12—Weight Assembly 6—
Shaft
Bushing 13—Cap
7—
Gear
begins
to misfire, then
give
the wrench one-half

turn
in the
opposite
direction (counterclockwise),
thus giving the approximate cam dwell angle re­
quirement

Note:
Prestolite and Delco distributors are inter­
changeable on V-6
engine
equipped vehicles.

c.
Dauntless V-6 Engine (Prestolite).
•
Refer to Fig. C-l5.

The
Prestolite distributor installed on the V-6
engine
is similar in construction to the distributor
installed on the F4
engine
except for the addition
of a vacuum advance mechanism.

The
spark advance is fully automatic being con-
FIG.
C-14—ADJUSTING CONTACT POINT GAP —
DAUNTLESS V-6 ENGINE (DELCO) trolled by built-in centrifugal weights, and by a

vacuum
advance system.

The
same service checking procedure outlined
in
Par.
C-lOa,
are used for the Prestolite V-6

distributor
with exception of specifications. 12963

FIG.
C-15—-PRESTOLITE DISTRIBUTOR V-6 ENGINE
1—
Vacuum
Advance Unit
5—Lubricating
Wick

2—
Distributor
Points 6—Condenser

3—
Breaker
Arm Pivot 7—Adjusting
Eccentric
Screw
4—
Distributor
Cap 8—Adjusting
Lock
Screw
(Rotation
&
Firing
Order)
Specifications for the V-6 Prestolite distributor are
as follows. The condenser capacity must be .25 to 28 mfd., contact breaker arm tension 17 to 22
ounces [482 a 624 gr.], and breaker point gap .016" [0,406 mm.]. The cam angle must be set
at 29° ±3° with distributor vacuum line discon­
nected.

C-11.
Replacement and Adjustment of Prestolite

Distributor Point
Set — V-6
Engine

Replace
the Prestolite distributor contact set as
follows:
a.
Remove the distributor cap from the distributor.
Remove the rotor.
b. The condenser and primary leads are retained
by breaker point spring tension. Refer to Fig.

C-12
and C-15. Relieve spring tension to remove
the leads.
c. Remove the contact set retaining screw and remove the contact set.

d.
Remove the condenser screw and remove the condenser.
e.
Install
new parts by reversing the removal pro­
cedure. Relieve spring tension of the breaker point

spring
to install the primary and condenser leads.

f.
Rotate the crankshaft until the distributor cam
holds the distributor points to a wide-open position.

Check
the gap
between
the points. Then slightly

loosen
the contact set mounting screw and adjust
the contact point gap to the proper dimension.

Tighten
the mounting screw when correct gap is attained.
C-12. Breaker
Lever
Spring Tension
One
of the most important items to check is the

breaker
lever spring tension.
This
is checked with

a
spring scale hooked immediately behind the

breaker
lever contact. Spring tension required to
open the contact points are given in Par. C-10. 27

c

TUNE-UP
C-13. Replacement and Adjustment of

Delco
Distributor Point Set

When
inspection of the contact points show re­ placement to be advisable, the following procedure
should be used. See Fig. C-13.

Note:
The service replacement contact point set
has the breaker spring tension and point alignment
adjusted at the factory.

Removal
of
Contact Point
Set

a.
Remove distributor cap by inserting a screw­

driver
in upper slotted end of cap retainers,
press

down and turn 90° counterclockwise. Push distri­
butor cap aside and remove rotor. Disconnect the condenser and primary leads from their terminal
by loosening the retaining screw. If there is no

retaining
screw, simply slip leads out.
b. Loosen two screws and lock
washers
which hold
the contact point set in place. Then remove point
set.

Installation
of
Contact Point
Set.

a.
Slide contact point set over
boss
on breaker
plate and under the two screw heads. Tighten two
screws and lock washers.

b.
Install
condenser and primary leads.

Note:
Leads must be properly positioned so they

will
not
come
in contact with
bottom
of weight
base or rotor.

c.
If
engine
does
not start readily, position contact

arm
rubbing block on peak of cam lobe, insert
V%"
[3,86 mm.] Allen wrench in adjusting screw and

turn
screw in (clockwise) until contact points

just
close. Then back screw out (counterclockwise)
V2
turn
(180°)
to obtain a point gap of approxi­
mately .016" [0,406 mm.] for a preliminary setting.

Adjustment
of
Contact Points
—
Engine Running
Note:
When adjusting contact point dwell angle,
always follow the instructions which
come
with the

dwell
meter.

a.
Connect dwell tester leads: red to distributor
side of coil, black to ground.

b. Turn
selector switch to position for
6-lobe
cam.

Turn
ignition switch on.

c.
Start engine.
Lift
adjustment window and insert
Vs"
[3,86 mm.] Allen wrench in adjusting screw.
Set dwell angle at 30 degrees. See Fig. C-14.

d.
After adjusting dwell angle, always check
ignition timing.

C-14.
Check
Ignition
Timing

a.
Hurricane F4 Engine.
If
a neon timing light is available, use it to check
igntion timing following the instructions of the
timing light manufacturer.

In
the absence of a timing light, remove No. 1

spark
plug and turn the
engine
over until No. 1
piston is on compression stroke as indicated by
air
being forced from No. 1 spark plug opening.
Turn
the
engine
slowly until the specified
degree
mark
on the timing gear cover is in alignment with
FIG.
C-l6—HURRICANE
F4
ENGINE

TIMING
MARKS
the notch on the crankshaft pulley. Fig. C-l6 shows
the timing pointer arrangement of the Hurricane
F4
engine. Refer to Ignition Timing Specifications
Par.
C-30. When the piston is positioned 5°
BTC,

timing is correctly set if the distributor rotor arm
points to No. 1 terminal in the distributor cap and
the distributor points are just ready to break. See
Fig.
C-12. Timing may be altered by loosening the

distributor
mounting clamp and turning the distri­
butor.
Turn
the distributor clockwise to advance
the timing and counterclockwise to retard the tim­
ing.
Do not overtighten the mounting clamp screw.
FIG.
C-l7—DISTRIBUTOR ROTATION
AND

FIRING
ORDER,
F4
ENGINE b.
Dauntless V-6 Engine.

Check
timing with a timing light connected to the

spark
plug of No. 1 cylinder (front cylinder, left

bank).
Yellow timing
mark
on the vibration damper must align with the specified
degree
mark

on the timing indicator (Fig.
C-18).
Refer to
Igni­

tion Timing Specifications Par. C-30. With the
engine
running at correct idle speed and the vacu­

um
advance
hose
disconnected from the distributor

and
the line plugged, check for correct timing
set­

ting. If necessary,
loosen
the distributor clamp bolt

and
rotate the distributor until proper alignment of timing marks is attained. Tighten mounting

screw.
After correct setting is made, unplug the

vacuum
line and reconnect it, operate the
engine
and
check operation of the vacuum advance.

Note:
Turn
the distributor counterclockwise to ad­
vance timing; turn clockwise to retard timing. 28

'Jeep'
UNIVERSAL
SERIES
SERVICE
MANUAL

C

FIG.
C-18—DAUNTLESS
V-6
ENGINE
TIMING
MARKS
C-15.
Primary
Circuit
Tests

Excessive
voltage
drop in the primary circuit
will

reduce the secondary output of the ignition coil,
resulting in hard starting and poor performance. Inspect all primary wiring for
loose
or corroded
terminals, worn insulation, and broken strands,
a.
Connect voltmeter positive (-J-) lead to the
positive battery terminal, as shown in Fig. C-20.
The
negative
lead (—) is connected to the ignition
side of the resistor on Dauntless V-6
engine.
The

negative
lead (—) is connected to the ignition
pri­

mary
of the coil on Hurricane F4
engine.
Con­
nect a jumper wire from the distributor primary

terminal
of the coil to the ground. Be sure all lights and accessories are off. b. With the ignition switch on, the
voltage
should
not
exceed
.4 volts. More than .4
volts
indicates

excessive
resistance
exists
in the battery cable, ignition switch wiring, or the ignition switch. The

excessive
resistance may be located with voltmeter checks across each section of the circuit.
c. Remove the jumper wire from the coil. Connect
the voltmeter positive (-f) lead to the distributor
terminal
of the ignition coil. Ground the
negative
(—) lead of the voltmeter.
12156
FIG.
C-20—IGNITION
PRIMARY
CIRCUIT

RESISTANCE
CHECK

1—
Distributor

2—
Distributor
Primary
Terminal

3—
Coil

4— Ignition Resistor 5— Ignition Switch 6— Ignition Switch Side of Resistor 7— Positive Battery
Terminal

8—
Battery

9—
Jumper
Wire
d.
Note
the
voltage
with the ignition switch on.

If
battery
voltage
is indicated, the distributor

breaker
points
are open. Rock the
engine
to
close

the points. Voltage
less
than .2 volt indicates the

points
are satisfactory. Voltage more than .2 volt indicates burned or high resistance in the ignition

points
or a poor distributor ground.

C-l
6. Distributor
Resistance
Test

A
dwell tester is used for the following
tests.
Ex­
cessive resistance in the ignition primary circuit,
from the distributor side of the coil through the

points
and to the distributor ground,
will
prevent
the coil from producing sufficient output for
good
overall
ignition. Any resistance in this portion of
the ignition system
will
be indicated on the dwell
FIG.
C-21—DISTRIBUTOR
RESISTANCE
CHECK

14242

FIG.
C-19—DISTRIBUTOR
ROTATION
AND
FIRING
ORDER,
V-6
ENGINE

29

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