1953 JEEP CJ air condition

F2
EXHAUST EMISSION CONTROL SYSTEMS
F2-3L
EXHAUST EMISSION CONTROL SYSTEM
DIAGNOSIS
GUIDE

Pump Noisy
Hoses Touching Other Parts of Engine or Body (Hood).

Note:
The Air Pump is not completely noiseless.

Under
normal conditions, pump
noise
rises in pitch as
engine
speed
increases. It is desirable to allow
for normal break-in wear of the pump prior to re­
placement for
excessive
noise.
Pump Seized
Replace pump.
-
do not pry on housing.
Leak
In Hose

Check
for leaks; using
soap
and water, tighten clamps or replace
hoses.

Pump Inoperative
Loose Belt — tighten belt
-

Filter
Plugged — replace.

Exhaust
Backfire

Check
for vacuum leaks — correct as necessary.
Check
anti-backfire valve — replace as necessary
Induction System Backfire

Verify
engine
timing and distributor dwell.
Verify
accelerator pump charge.

F2-32.
EXHAUST EMISSION CONTROL SYSTEM MAINTENANCE CHART

Efficient
performance of the Exhaust Emission very important that all of the maintenance require-

Control
System is
dependent
upon precise main-
ments
are performed with extreme care at the
tenance. As indicated in the following chart, it is specific interval indicated.
Thousands of miles* or

OPERATION
number of months whichever occurs first 2 6 12 18 24 30
Inspect engine-driven
belts
for condition and tension R R
Replace positive crankcase ventilation valve
(PCV)
R R

Check
for free operation of exhaust manifold heat control valve O O O O O

Clean
carburetor air cleaner — Oil Bath O O O O O
Replace carburetor air cleaner
element
— Dry Type O
Check
heated air system O O

Engine
tune-up O O

Check
engine
timing R O O O
Adjust
carburetor idle
speed
and mixture R O O O

Perform
factory-recommended road
test
for evaluation of overall performance and handling O O O O O

R
— Required Services O — Recommended Services

*
Miles Kilometers
2,000
—
3,200

6,000
—
9,600

12,000
—
19,200 18,000
—
28,800
24,000
—
38,400
30,000
—
48,000

F2-33.
GENERAL SPECIFICATIONS
Air
Pump Belt Tension 60 lb.

Rotor
Ring Screw Torque . 37 lb-in.
Housing Cover Bolt Torque 10 lb-ft. Speed Ratio, Air Pump to Engine
1
\i to 1

F2-34.
EXHAUST EMISSION CONTROL SYSTEM CARBURETOR SPECIFICATIONS

Make
Rochester Model Designation 2G Code Number
7027082
—
7041185

Choke
Manual
Number of Barrels 2

Throttle
Bore... \W [3,65 cm.]
Main
Metering Jet Production .051" - 60° [1,29 mm.]
High
Altitude — over
5000
ft .049" - 60° [1,24 mm.]
—
over
10,000
ft .047" - 60° [1,19 mm.]

Float
Level
Adjustment* 1%," [2,94 cm.]
Float
Drop Adjustment l%" [4,76 cm.]
Pump Rod Adjustment** 1%" [2,94 cm.]
Engine
Idle
R.P.M.
(In Neutral) 650 to 700

Initial
Idle Speed-screw
setting
3 turns in

Initial
Idle Mixture-screw
setting
2 turns out
Dash
Pot Setting. Y%w [3,75 mm.]
*From
air horn gasket to top of float at toe.

**From
air cleaner ring to top of pump rod.
158

'Jeep*
UNIVERSAL SERIES SERVICE
MANUAL

G

FIG.
G-4—PRESSURE TESTING COOLING SYSTEM
1—Pressure Tester C-3499 previous radiator leakage. These
spots
may not be
damp if water only or methyl-alcohol-base anti­ freeze is in the cooling system since such coolants
evaporate readily. An ethylene-glycol-base anti­ freeze shows up existing leaks as it
does
not evapo­
rate.
The radiator may be tested for leaks by using

a
Pressure Tester Tool C-4080, as shown in Fig.

G-2.

When
the pressure cap opens, the sudden surge of

vapor
or liquid must blow out through the overflow
pipe. If the overflow pipe is dented or clogged,
the pressure caused by obstruction may cause dam­
age to the radiator or
hose
connections in the cool-
1
FIG.
G-5—RADIATOR PRESSURE
CAP
1—
Pressure
Cap

2—
Overflow
Tube

3—
Pressure
Seal 4—
Vacuum
Release Valve
5—
Radiator
Neck
FIG.
G-6—TESTING RADIATOR PRESSURE
CAP
1—
Radiator
Pressure Cap

2—
Adapter

3—
Pressure
Tester C-3499 ing system. To remove clogging material, run a
flexible wire through the overflow pipe.
G-6.
Radiator Removal
and
Replacement
a.
Drain
the radiator by opening the
drain
cock

and
removing the radiator pressure cap.

b.
Remove the upper and lower
hose
clamps and

hoses
at the radiator.

c.
Remove the four cap screws, lock washers and
flat washers that secure the radiator to the radiator
body support. Remove the radiator.

d.
To replace the radiator, reverse the removal

procedure.

G-7.
Radiator
Hoses
and
Heater Hoses

Air,
heat, and water deteriorate radiator and heater

hoses
in two ways: by hardening or cracking which
destroys flexibility and causes leaks; by softening
and
swelling which produces lining failure and
hose

rupture
and clogging. Examine
hoses
spring and

fall
for possible need of replacement or tightening.

If
hoses
are collapsed, cracked, or indicate a
soft

condition on the inside they should be replaced.
Correct
installation of a new heater
hose
is impor­
tant to prevent contact between the
hose
and the
exhaust manifold. On the
Hurricane
F4 engine the
molded curved end of the
hose
connects to the
hot water intake of the heater; the flexible end to the hot water valve on top of the cylinder head.
On
the Dauntless V-6 engine the heater inlet
hose

is connected to the
rear
of the intake manifold 165

G
COOLING SYSTEM and
the outlet
hose
is connected to the water pump
housing.
When
installing a new hose, clean the pipe connec­
tions and apply a thin layer of nonhardening seal­
ing compound. Hose clamps should be properly
located over the connections to provide secure fastening. The pressurized cooling system pressure

can
blow off improperly installed hoses.

G-8.
Cylinder
Block

Any
coolant leaks at the engine block water joints

are
aggravated by pump pressure in the water

jacket
and by pressure developed in the cooling system when the pressure cap is in place.
Small
leaks showing up only as moist
spots
often
cannot
be detected when the engine is hot except by the
appearance of rust, corrosion, and dye stains where
leakage evaporated. Also, expansion and contrac­ tion of the engine block resulting from extreme
temperature changes can aggravate leaks. For
these

reasons, when checking for coolant leaks inspect
the block when it is cold and while the engine is

running.
A
leaking
drain
cock or plug that cannot be stopped

leaking
by tightening should be replaced.
Leaking

core-hole expansion plugs should be replaced.
If
tightening gasketed joints
will
not correct leak­
age, install new gaskets. Use a sealing compound
where recommended.

G-9.
Thermostat
a.
The cooling system of the engine is designed
to provide adequate cooling under most adverse conditions. However, it is necessary to employ
some

device to provide quick warming and to prevent
overcooling during normal operation. Automatic
control
of engine operating temperature is provided
by a water flow control thermostat installed in the
water
outlet of the
Hurricane
F4 engine. The ther­
mostat is a heat-operated valve. It should always
be maintained in working order and the vehicle
should never be driven without one installed as there would then be no control of engine tempera­

ture.
The temperature at which the thermostat
opens
is preset and cannot be altered.

b.
The thermostat on the
Hurricane
F4 engine is
located in a housing on the top front of the cylinder

head.
On the Dauntless V-6 engine it is located
in
the thermostat housing of the air intake manifold.

The
standard engine thermostat for the
Hurricane

F4
and Dauntless V-6 engine has a normal rating
of
190°F.
[87.8°C]
and should begin to open at

a
coolant temperature between
180°F.
[82°C]
to
192°F.
[89°C]
and be fully open at
202°F.
[94°C.].
See Fig. G-7 for method of testing.

When
the thermostat is not operating properly, the engine may
run
too hot or too cold. Overheating

may
damage the thermostat so that its valve
will

not function properly, and a cold engine
will
not achieve
full
efficiency.
Rust
can also interfere with
thermostat operation. To
test
the thermostat, place

it
in water heated approximately
25°F.
[17°C]
above the temperature stamped on the thermostat

valve.
Submerge the bellows completely and agitate
the water thoroughly. The valve should open fully.
Next, place the thermostat in water heated approxi-
FIG.
G-7—THERMOSTAT
TEST

mately 10°F.
[11°C]
below the temperature
stamped on the thermostat valve. Submerge the bellows completely and agitate the water thorough­
ly.
The valve should close completely. If the ther­
mostat fails either of
these
tests, it should be re­ placed with a new one of the same type and rating.

G-10. Temperature
Sending Unit

The
sending unit incorporates a temperature sens­ ing element that when it is surrounded by cold engine coolant, the unit provides the highest resist­
ance in the temperature
gauge
indicator
circuit.
Resultant
low current flow in the circuit causes the

indicator
on the instrument panel to read at the low (C) end of the
gauge.
As engine coolant tem­

perature
increases, the resistance of the unit is
decreased allowing an increased current flow in
the
circuit,
making the instrument panel
gauge

register in proportion to the temperature of the engine coolant.

To
test
the sending unit, first run the engine until

it
has had time enough to warm up.
If
no reading is indicated on the
gauge,
check the
sending unit to
gauge
wire by removing the wire

from
the sending unit and momentarily grounding
the wire. If the
gauge
now indicates, the sending

unit
is faulty. If the
gauge
still
does
not indicate, the wire is defective.
Repair
or replace the wire,

a.
Hurricane
F4 Engine.

The
thermo-couple coolant temperature sending
unit
is mounted in the right
rear
of the cylinder head (Fig. G-8) and is connected by a single wire
to the dash unit of the instrument cluster. 166

'Jeep'
UNIVERSAL
SERIES SERVICE
MANUAL

G
cation period. It is
good
preventive maintenance to
replace a badly frayed, worn or cracked fan belt
before it breaks in operation.

To
replace the fan belt,
loosen
the attaching
bolts

at each generator or alternator brace-to-engine mounting and pivot the alternator or generator to­

ward
the
engine
to gain slack needed to install the new belt Remove the old belt. Position the new
belt over the fan pulley, over the crankshaft pulley,
then over the generator or alternator pulley.
Pull
the generator or alternator away from the
engine

until
belt tension is
firm.
Then tighten the generator

or
alternator mounting
bolts
and check the tension
as indicated above. Reset the generator or alternator as necessary for correct belt tension.
Finally,
torque
the generator or alternator mounting
bolts
25 to 35 lb-ft. [3,4 a 4,8 kg-m.].

Note:
On the Dauntless V-6
engine
when adjusting
the fan belt tension, the alternator mounting
bolts

should be torqued 30 to 40 lb-ft. [4,14 to 5,53

kg-m.].
If a fan belt tension
gauge
(W-283) is
avail­

able, proper tension should be 80 pounds [36,2 kg.].

G-l
9. Engine Overheating

An
engine
will
not be damaged by high coolant
temperatures unless the coolant boils. The pres­

surized
cooling system on the 'Jeep' vehicles raises the boiling point of the coolant solution. Should
overheating be encountered, and the fault is be­
lieved to be in the cooling system check for the
following:

a.
Proper coolant level. See
Filling
Cooling Sys­
tem Par. G-2.
b. Poor air flow.
Check
for dirty radiator core. (See Radiator Par. G-5).
Check
for faulty belt
pulley operation, worn or
loose
fan belt, or dam­ aged fan.
Clean,
repair, replace or adjust as neces­

sary.

c. Foaming coolant.
Check
for air leaks at water
pump,
hose
connection and filler cap. Tighten, re­

pair
or replace as necessary.

d.
Surging or "after boil".
Check
pressure cap and
replace if valves or gasket are faulty.
e.
External
leaks.
Check
the following for leaks:
Hoses and clamps, water pump, radiator, head gas­
ket, core plugs and drain cocks, as well as the cylin­ der head or block for
cracks.

f.
Internal
leaks.
Check
for faulty head gasket,
cracked
cylinder head or block.
g. Poor coolant flow.
Check
hose
condition, water pump, fan belt, and repair or replace as necessary. Inspect block for rust or scale, and clean and flush
the system, if necessary.

h.
Check
the temperature
gauge.
169

H

ELECTRICAL
SYSTEM SUBJECT
PAR.

Directional
Signal
Lamps
H-138

Hazard
Warning
Lamps
H-139

Head
Lamp
Replacement H-130
Head
Lamp
Aiming Procedure H-131 Headlight Dimmer Switch H-127

License
Plate
Lamp
H-136
Main
Light
Switch. H-126

Marker
Lights .H-l40

Parking
and
Turn
Signal
Light
H-133
Stop
Light
Switch. H-l28
Tail,
Stop and
Turn
Signal
Lamp
.H-134

H-1. GENERAL
All
'Jeep' Universal vehicles are equipped with 12- volt electrical systems. Use caution around the higher
voltage
of the 12-volt system as accidental

short
circuits are more capable of damaging electri­
cal
units. Also, arcs around the 12-volt battery are
more apt to ignite any gas that may be escaping

from
it. In the following paragraphs
will
be found
information about the battery, distributor, coil,
generator, alternator,
voltage
regulator and start­ ing motor. These units with the connecting wires,

make
up the
engine
electrical system. The wiring
diagram
will
show the different circuits of the en­

gine
electrical system and the various units which
make
up
those
circuits.

With
plastic-covered wiring harnesses use only

rubber-insulated
wiring clips.

Caution:
All current production vehicles are 12- volt, negative ground. Whenever servicing a 12-
volt electrical system, use caution, as an accidental

short
circuit is capable of damaging electrical units. Disconnect battery ground cable before changing

electrical
components.

H-2.
Battery

The
battery is a storage reservoir for electrical
energy produced by the alternator or generator.
The
battery should store sufficient energy for
operation of the entire electrical system when the
alternator
or generator is not pr 1,scing output,

such
as when the ignition is first turned on. Of

particular
importance is maintaining the electrolyte
at the correct level, regularly checking with a
hydrometer, and maintaining clean, tight cable connections.

Battery
service information is given in this section.

Caution:
Do not allow flames or sparks to be
brought near the vent
openings
of the battery since
hydrogen gas may be present in the battery and might explode.

Note:
The liquid in the battery (electrolyte) is a
solution of sulphuric acid which, on contact, can

injure
skin or
eyes,
or damage clothes. If it is spilled
on the skin or spattered in the
eyes,
promptly flush
it
away with quantities of clear water only. If the

acid
is spilled on clothes, wet it thoroughly with a

weak
solution of ammonia, or with a solution of sodium bicarbonate or baking soda.
SUBJECT
PAR.

HORN
H-137

ELECTRICAL
COMPONENT
REPLACEMENT
H-150

WINDSHIPLD
WIPER SYSTEM
H-141
thru
149

SERVICE
DIAGNOSIS.
. .H-151

ELECTRICAL
SPECIFICATIONS
H-152

Caution:
When installing the battery, the nega­
tive terminal must be grounded. Reverse polarity of the battery can cause severe damage to the charg­ing system.

Battery
Inspection

a.
Check
the specific gravity of the electrolyte in
each cell of the battery. A hydrometer reading of 1.260 indicates that the battery is fully charged.

If
the reading is 1.225 or below, the battery
needs

recharging.
If one or more cells is 25 "points" (.025) or more lower than the other cells, this in­
dicates that the cell is shorted, the cell is about to

fail,
or there is a
crack
in the battery partition in
the case. Unless the battery is repaired or replaced, battery trouble
will
soon
be experienced.

b.
Check
the electrolyte level in each cell, add

distilled
water to maintain the solution [9,5 mm.] above the plates. Avoid overfilling. Replace
the filler caps and tighten securely. It is important to keep the electrolyte level above the plates at all
times because plates that are
exposed
for any
length of time
will
be seriously damaged.

c.
Check
the wing nuts on the hold-down frame for tightness. Tighten them only with finger pres­

sure,
never with pliers or a wrench. Excessive
pressure
could damage the battery case.

d.
Clean
the battery terminals and cable con­ nectors. Prepare a strong solution of baking soda

and
water and brush it around the terminals to
remove any corrosion that is present. The cell caps must be tight and their vents sealed to prevent
cleaning solution entering the cells. After cleaning,
connect cables to battery and coat the terminals

with
heavy grease.

e.
Inspect the battery cables and replace if badly
corroded
or frayed.
Check
tightness
of terminal
screws to ensure
good
electrical connections.
Check

the
tightness
of the negative ground cable con­nection at the frame to ensure a
good
ground
connection.
f.
Load
test
the battery. Connect a voltmeter across the battery. Run the starting motor for 15 seconds. If the
voltage
does
not drop below 10
volts the battery is satisfactory. If the
voltage
falls
below the figure given, yet the specific gravity is
above
1.225,
the condition of the battery is questionable.
g. Be sure the
engine
ground strap connection, 172

'Jeep'
UNIVERSAL
SERIES SERVICE
MANUAL

H

12746

FIG.
H-l8—VACUUM
ADVANCE
MECHANISM
(DELCO)

A—Full
Advance

B—No
Advance
1—Vacuum
Pull
Rod
e.
To adjust breaker point cam dwell and set tim­
ing of engine, refer to
Pars.
C-10 and
C-ll.
H-31. Coil
— V-6 Engine

The
sealed coil
does
not require any special service
other than keeping the terminals and wire connec­
tions clean and tight.

The
positive (+) terminal of the coil is connected
to the ignition switch through the ballast resistor,
and
is also connected directly to the starter
sole­

noid to by-pass the resistance during cranking of
engine.
The
negative (—) terminal is connected to the

distributor.
The secondary (high tension) terminal
is connected by a short cable to the center terminal
in
the distributor cap.

Always
make certain the coil wires are connected to the proper coil terminals to ensure correct
coil
polarity.

Note:
The ignition coil and ballast resistor must
be of the same manufacturer. Ballast resistors
and
ignition coils of one manufacturer are inter­changeable with both units of the other. H-32.
Ballast
Resistor

•
V-6 Engine.

An
ignition ballast resistor is in series with the
primary
winding of the coil. The ballast resistor
helps regulate the flow of
primary
current through­
out the speed range. At low
speeds
when the con­
tacts remain closed longer, the ballast heats and
increases in resistance, thereby limiting the flow of

primary
current. At higher
speeds
when the con­
tacts remain closed for shorter periods of time, the ballast
cools
and thereby decreases in resistance
to allow more
primary
current and reduce the
fall

off
in
available voltage.
During
starting, the resistor compensates for the lowered battery
voltage
re­
sulting from the starter load and permits an in­ crease in
primary
current, resulting in a higher
secondary
voltage
for starting.
The
only
test
required of the ignition ballast re­
sistor is a continuity check. Characteristics of the ballast produce wide variations in resistance with
changes in ballast temperature. Therefore, check­ ing
voltage
drop across the ballast would be mis­
leading.

Caution:
Never make a connection that connects
the ballast across the battery as this
will
burn
the ballast resistor winding.

H-33.
Spark
Plugs

Clean
and gap
spark
plugs as described in
Par.
C-4.
Inspect them for excessive burning and erosion of
electrodes, blistering of porcelain at the firing tip,

black
deposits, or fouling. These conditions indicate
that the plugs have not been operating at the cor­

rect
temperature.

Note:
Prolonged idling just before removing and
checking the plugs should be avoided as it may
produce false indications.

Spark
plug operating temperatures may have been
too hot, too cold, or normal as described.

a.
At too hot a temperature, the tip of the insulator
will
show
dark
spots
and blisters after fairly short service. As high-temperature operation is con­
tinued, the whole insulator
nose
will
discolor, show­
ing fused and blistered
deposits
near the electrode
as well as considerable erosion and burning of the
electrodes. After extreme service, the porcelain it­ self may be fused, cracked, and blistered at the tip.

The
electrodes
will
show extreme erosion and
burn­

ing and possibly even surface cracking.

Note:
If such cracking appears on certain plugs
after fairly short service, it may be caused by water
leaks in the associated cylinders.
b. At too cold a temperature plug operation, in
the early
stages,
will
result in a
dull
black
sooting

of the plug.
This
condition frequently is found in new vehicles during the break-in period and is no
indication of trouble in this case. As the condition progresses, black
deposits
of oil and carbon build
up on the base of the shell and on the insulator

until,
in extreme cases, the space
between
insulator

and
shell may be almost completely filled. Excessive
electrode erosion
will
seldom be found in cases of cold plug operation. These indications can be pro­
duced by the use of an excessively
rich
air-fuel mixture and the carburetor should be checked if
this condition is suspected. Fouling
will
also be
caused by leaking rings or intake valve
guides
that
permit excessive oil to reach the combustion
chambers.
The use of a hotter plug
will
help
burn

away
some
of this fouling but the mechanical con­ dition of the
engine
should be corrected.
c. In normal temperature operation the plug
will
accumulate grayish-tan to reddish-brown
deposits

with
fairly uniform discoloration of the insulator
nose
and slight, localized electrode erosion. If the
insulator shows any blotches, blisters,
irregular
dis­
coloration, etc., look for hot-plug symptoms. Too
hot or too cold plug operation may be caused by
the use of plugs of other than the specified heat

rating
but if the plugs are as specified a hotter or 187

H

ELECTRICAL
SYSTEM
colder plug may be desirable. However, under- or
over-heating is usually caused by factors other than the type of
spark
plugs and the cause should be determined before changing plugs. The design of the
engine
calls for plugs equivalent to Champion

J-8
for F4
engines
and
A.C.
44S or
UJ12Y
Champ­

ion for the V6 engines, (as installed in production)
though any factor that consistently affects
engine
operating temperature may cause this requirement
to change. Overheating may be caused by in­ sufficient tightening of the plug in the head, which interferes with the flow of heat away from the firing

tip.
If this is the case, the plug gasket
will
show very
little flattening. Over-tightening, in
turn,
will
pro­ duce too easy a heat flow path and result in cold
plug operation.
This
will
be evident by excessive
flattening
and
deformation of the gasket.
Prevailing
temperatures, condition of the cooling system, and

air-fuel
mixture can affect the
engine
operating temperature and should be taken into consideration.
H-34.
GENERATOR
— F4
ENGINE

The
generator is an air-cooled, two-brush unit

which
cannot be adjusted to increase or decrease output. For replacement,
voltage
regulator and generator must be matched for
voltage
and capa­

city,
polarity, and common source of manufacture.
Otherwise,
either a
loss
of ampere capacity or a

burned
out generator
will
result. Generators for

these
vehicles are 12-volt. Par. H-l explains the 12-volt system. Refer to the specifications at the
end of this section for information on correct generator rating for a specific model series.
The
circuit
breaker,
voltage
regulator, and current-

limiting
regulator are built into one combination

unit.
Because the regulator and battery are part
of the generator
circuit,
the output of the generator
depends upon the
state
of charge and temperature
of the battery.
With
a discharged battery, the
output
will
be high, decreasing proportionally as the battery
becomes
charged. For service informa­
tion covering current regulator see Par. H-41.

H-36.
Generator
Maintenance

A
periodic inspection should be made of the charg­
ing
circuit,
Fig. H-l9. The interval
between
these
checks
will
vary
depending upon type of service.
Dust,
dirt
and high speed operation are factors 10541

FIG.
H-19—CHARGING
CIRCUIT

1—
Battery
4-—Starter Switch

2—
Voltage
Regulator 5-—Charge Indicator

3—
Generator
which
contribute to increased wear of bearings

and
brushes.

Under
normal conditions a check should be made
each 6000 miles
[9.600
km.].

A
visual inspection should be made of all wiring,
to be sure there are no broken or damaged wires.

Check
all connections to be sure they are tight and

clean.

Should
the commutator be rough or worn the
armature
should be removed and the commutator

turned
and undercut. See Par. H-37.
The
brushes should slide freely in their holders.

Should
they be oil soaked or if they are worn to

less
than one-half their original length they should
be replaced. When new brushes are installed they should be sanded to provide
full
contact with the
commutator. Generators should not be checked for
output until the brushes are seated.

Brush
spring tension is important. High tension causes
rapid
brush and commutator wear while
low tension causes arcing and reduced output.
Test
the tension with a spring scale.
Check
the
specifications section at end of this section for

correct
spring tension for generator in question.
H-36.
Generator Disassembly
•
Refer to Fig. H-20:
Before beginning disassembly of the generator to

correct
electrical system malfunctions proceed with
inspection and
test
procedures as detailed in Par.

H-46
thru
H-62. If it is definitely determined that trouble exists within the generator, which ne­cessitates dismantling, proceed as follows. Remove the two frame screws in the commutator
end plate and remove the end plate assembly. Next
pull
the armature and drive head complete

from
the generator housing. Remove the generator pulley from the armature by removing the nut

and
washer. Do not
lose
the Woodruff key when
the pulley is removed. After this, remove the drive
end head assembly which includes the oil seal and
bearing.
To remove the bearing, remove the three
screws and lockwashers in the grease retainer and remove the retainer and felt washer, after which,
remove the bearing, oil guard and felt washer.
H-37.
Armature

If
the commutator is rough or worn,
turn
it down

in
a lathe. After turning, the mica insulation be­ tween the
segments
should be undercut to a depth of 34* [0,8 mm.].
To
test
the armature for a ground, connect one

prod
of a
test
lamp to the core or shaft (not on

bearing
surface) and touch each commutator
seg­
ment with the other prod. If the lamp lights, the

armature
segment
is grounded and the armature must be replaced.

To
test
for short in armature coils, a growler,

Fig.
H-21, is necessary. Place the armature on the growler and lay a thin steel strip on the armature

core.
The armature is then rotated slowly by hand

and
if a coil is shorted, the steel strip
will
vibrate.

Should
a coil be shorted the armature must be
replaced.

If
precision
test
equipment is available, the cus­

tomary
accurate
tests
can be made in accordance 188

H

ELECTRICAL
SYSTEM
terminal
and bracket. Test lamp should not light.

If
it
does,
the
brush
is shorted and must be replaced,
b.
Connect one lead of an ohmmeter to field ter­

minal
and the other lead to insulated brush. Re­
sistance reading should be zero. Move brush and

brush
lead wire to make certain that the brush lead wire connections are not intermittent. Resist­
ance reading should not vary when brush and lead

wire
are being moved.

C.
Connect ohmmeter leads to bracket and grounded brush. Resistance reading should be zero.
Repeat same
test
on brush lead wire as described

in
step
b above.
FIG.
H-30—INSULATION
AND
CONTINUITY

TEST
POINTS
1^-Brackct

2—
Field
Terminal

3—
Grounded
Brush

4—
Insulated
Brush

H-76.
Rotor
In-Vehicle
Tests

a.
Reference Par. H-73, Fig. H-28.
b.
To check for a short circuit in the rotor wind­
ings, the alternator should be removed. Refer to

Par.
H-79 for rotor bench
tests.

H-77.
ALTERNATOR
BENCH
TESTS

When
the various
tests
given in
Par.
H-69 through
H-76 have determined a fault within the alternator itself, the alternator should be removed from the vehicle and the following
tests
given in
sequence

to isolate the trouble to a particular
component

of the alternator.
Note
that certain
tests
can be
performed after the alternator is removed and
before
it is disassembled.

H-78.
ALTERNATOR
REMOVAL
Note:
Brushes and isolation
diode
can be removed

from
alternator without removing unit from vehicle.

a.
Disconnect all lead connections at alternator.
b.
Remove nut and
bolt
at alternator support

bracket.
Remove nut, bolt, washer, and adjustment

bracket.
Remove belt from alternator pulley. The alternator is now free to be removed from the
vehicle.

H-79.
Rotor Tests
—
Bench

This
test
checks the condition of the rotor (field coil) for
open
or shorted field winding, excessively

worn
or sticky brushes, and
open
connections. It should be performed with the brush assembly in­
stalled in the alternator.

a.
The field coil is checked for a short circuit
by connecting a fully charged battery and an ammeter in series with the two slip rings.

A
rheostat is placed in series in the
circuit
to protect
the instruments and
components
of the alternator. Set rheostat to maximum resistance (40 ohms)

before
making connections.

b.
Slowly reduce resistance of rheostat to zero.

Then
take reading on ammeter. With full battery
voltage
applied to the field coil, the field current
of the 35-amp. alternator should be 1.7 to 2.3 amp.

Note:
The field current of the 40 and 55 amp.
alternator should be 1.8 to 2.4 amps with full battery
voltage
applied to the field coil.
c.
Turn
rotor by hand, noting reading. Rotating
rotor
will
indicate if brushes are making
good
elec­

trical
contact. A slight fluctuation of reading (0.2

amp.)
is to be expected.
If
field current is not within limits, inspect brushes

and
slip rings for
excessive
dirt, sticky, or broken
brushes, and bad connections.
Check
brush as­ sembly for short and continuity (Par. H-75). Make
same
test
to slip rings. Reinstall repaired or known
good
brush assembly and repeat
test.
If
the field current is
above
the maximum value
specified, it indicates that the field coil is either
shorted to rotor or field coil has shorted windings.
If
the field current is zero, it indicates that the field

coil
or coil-to-slip ring connection is open. If the field
current
is considerably
less
than the value
specified, it indicates a poor coil-to-slip ring con­ nection or poor brush-to-slip ring connection.

d.
To check continuity of the rotor, disconnect the
battery and connect an ohmmeter directly across
the field. Resistance
between
field terminal and ground terminal should be approximately 6 ohms.
If
resistance is high, field coil is shorted.

e.
If rotor is found to be
defective
in
above
tests,
repeat the
above
tests
when the rotor is removed

from
the alternator by connecting the
test
circuit
to rotor slip rings to ascertain findings.
Field
current

will
be approximately 0.2 amp. higher than the
maximum
value because of the normal brush-to-

slip-ring
contact resistance that reduces field
current
slightly. If the rotor is found to be de­
fective, it should be replaced.

H-80.
Alternator Disassembly

Refer
to Fig. H-31.

a.
Remove brush assembly by removing two tap­ ping screws and cover. Then pull the brush as- 198