1953 JEEP CJ belt

'Jeep'
UNIVERSAL
SERIES SERVICE
MANUAL

Dl
Dl-104.
SERVICE
DIAGNOSIS

Poor Fuel Economy
Ignition Timing Late or Spark Advance Inoperative

Carburetor
Float Setting Too High
Accelerator Pump Improperly Adjusted
Fuel
Pump Pressure High

Fuel
Line
Leakage

Fuel
Pump Diaphragm Leakage
Cylinder
Compression Low
Valves Do Not Seat Properly
Spark
Plugs
Defective

Spark
Plug Cables
Defective

Ignition
Coil
or Capacitor
Defective

Carburetor
Air Cleaner Dirty

Brakes
Drag
Wheel Alignment Incorrect

Tire
Pressure Incorrect Odometer Inaccurate

Fuel
Tank
Cap Clogged or
Defective

Muffler or Exhaust Pipe Clogged or Bent

Lack
of
Power
Cylinder
Compression Low
Ingitdon Timing Late

Carburetor
or
Fuel
Pump Clogged or
Defective

Fuel
Lines Clogged
Air
Cleaner Restricted
Engine Temperature High Valves Do Not Seat Property

Valve
Timing Late Intake Manifold or Cylinder Head
Gasket Leaks
Muffler or Exhaust Pipe Clogged or Bent
Spark
Plugs Dirty or
Defective

Breaker
Point Gap Incorrect
Breaker
Points
Defective
Ignition
Coil
or Capacitor
Defective

Electrical
Connection Loose
Broken
Valve Spring

Broken
Piston Ring or Piston
Cylinder
Head Gasket
Defective

Distributor Cap Cracked

Low
Compression
Valves Not Seating Properly Piston Rings Seal Poorly
Valve
Spring Weak or Broken
Cylinder
Scored or Worn
Piston Clearance Too Great

Cylinder
Head Gasket Leaks

Burned
Valves and
Seats
Valves Stick or Are Too Loose in Guides
Valve
Timing Incorrect

Valve
Head and Seat Have Excessive Carbon
Engine Overheats

Valve
Spring Weak or Broken

Valve
Lifter Seized or Collapsed
Exhaust
System Clogged
Valves Sticking

Valve
Stem Warped

Valve
Stem Carbonized or Scored

Valve
Stem Clearance Insufficient in Guide

Valve
Spring Weak or Broken

Valve
Spring Distorted
Oil
Contaminated

Overheating
Cooling System Inoperative
Thermostat Inoperative Ignition Timing Incorrect

Valve
Timing Incorrect
Carbon
Accumulation Excessive

Fan
Belt Loose
Muffler or Exhaust Pipe Clogged or Bent

Oil
System Failure
Piston Rings Worn or Scored
Popping,
Spitting,
Detonation
Ignition Timing Incorrect

Carburetion
Improper

Carbon
Deposit
in Combustion
Chambers Excessive
Valves Not Seating Properly
Valve
Spring Broken
Spark
Plug Electrodes Burned
Water or Dirt in
Fuel
Fuel
Line
Clogged
Valve
Timing Incorrect

Excessive
Oil
Consumption
Piston Rings Stuck in Grooves, Weak,
Worn,
Broken, or Incorrectly Fitted

Crankshaft
Main Bearings or
Connecting Rod Bearings Have
Excessive Clearance
Gaskets or Oil Seals
Leak

Cylinder
Bores Worn, Scored,
Out-of-Round or Tapered
Pistons Have Too Great Clearance to Cylinder Bores
Connecting Rods Misaligned High Road Speed
High Temperature

Crankcase
Ventilation System Inoperative
Bearing Failure
Crankshaft
Bearing Journal Rough or Out-of-Round

Oil
Level Low
Oil
Leakage

Oil
Dirty
Oil
Pressure Low or Lacking
(Oil
Pump Failure)

Drilled
Passages
in Crankshaft or
Crankcase
Clogged

Oil
Screen Dirty
Connecting Rod Bent 105

'Jeep'
UNIVERSAL SERIES SERVICE
MANUAL

Fl
EXHHUST
EMISSION
CONTROL
SYSTEM

Contents

HURRICANE
F4-134
ENGINE
SUBJECT
PAR.

GENERAL
Fl-1

AIR
PUMP
Fl-2

PUMP
AIR
FILTER
Fl-3

AIR
DELIVERY
MANIFOLD
Fl-4

AIR INJECTION TUBES.
Fl-5

ANTI-BACKFIRE
DIVERTER
VALVE.
.Fl-6

ENGINE
COMPONENTS
. .Fl-7
Carburetor
. .Fl-8

Distributor
........
.Fl-9
Exhaust
Manifold Fl-10

MAINTENANCE
Fl-11
Carburetor
Fl-12,
Fl-13

Distributor
Fl-14

Anti-Backfire
Diverter
Valve.
.........
.Fl-15

Check
Valve Fl-16

Fl-1. GENERAL—F4-134
Engine

The
Hurricane
F4-134
engine
Exhaust
Emission
Control
System consists of a belt driven air pump

which
directs compressed air through connecting

hoses
to a steel distribution manifold into stainless steel injection
tubes
in the exhaust port adjacent
to each exhaust valve stem.
This
air with its normal

oxygen
content, reacts with the hot but incom­
pletely burned exhaust
gases
and permits further combustion in the exhaust port or manifold.
Fl-2. AIR
PUMP

The
air injection pump is a positive displacement
vane type which is permanently lubricated and
requires
no periodic maintenance.

The
pump contains an integral relief valve which controls the air supplied to the
engine
exhaust ports

during
high speed operation to limit maximum ex­
haust system temperatures.

Fl-3. PUMP
AIR
FILTER

The
air filter attached to the pump is a replaceable
element type constructed of conventional pleated
paper
with steel end plates.

The
filter should be replaced every
12,000
miles
[19,200
km.] under normal conditions or sooner

under
adverse weather or driving conditions.

Fl-4.
AIR
DELIVERY
MANIFOLD

The
air delivery manifold, constructed of cold
rolled
steel with a zinc plating, distributes the air

from
the pump to each of the air delivery
tubes

in
a uniform manner.

A
check valve is attached to the air delivery
SUBJECT
PAR.

Air
Pump Fl-17
Carburetor
Air Cleaner Fl-18

REMOVAL PROCEDURES
.Fl-19
Air
Pump
Fl-20
Anti-Backfire
Diverter Valve Fl-21
Air
Distribution Manifold,
And
Air Injection Tubes
Fl-22

REQUIRED
EQUIPMENT
.Fl-23

REPLACEMENT
PARTS
Fl-24

WARRANTY
Fl-25

DIAGNOSIS
GUIDE
Fl-26
MAINTENANCE CHART
Fl-27

CARBURETOR SPECIFICATIONS
Fl-28

DISTRIBUTOR SPECIFICATIONS
Fl-29
SPARK PLUG
GAP
.Fl-30

manifold.
Its function is to prevent the reverse flow
of exhaust
gases
to the pump should the pump
drive
fail.
This
reverse flow would damage the air
pump and connecting
hose.

Fl-5.
AIR
INJECTION
TUBES

The
air injection
tubes
of stainless steel are inserted
into machined
bosses
of the exhaust manifold. The

tubes
project into the exhaust ports directing air
into the vicinity of the exhaust valve stem.

Fl-6.
ANTI-BACKFIRE DIVERTER VALVE

The
anti-backfire diverter valve prevents
engine
backfire
by briefly interrupting the air being in­
jected into the exhaust manifold during periods of deceleration (rapid throttle closure).

Fl-7.
ENGINE
COMPONENTS

The
following items
vary
in design or specifications

from
those
on vehicles not equipped with the Ex­
haust Emission
Control
System.

Fl-8.
Carburetor

A
carburetor with a specific flow characteristic is used for exhaust emission control.

A
carburetor dashpot is provided to control the throttle closing speed.

Fl-t.
Distributor

The
ignition distributor used with the exhaust emission system requires a different advance curve

from
that used on the F4-134
engine
prior
to the
introduction of exhaust emission systems. 143

'Jeep'
UNIVERSAL
SERIES SERVICE
MANUAL

Fl
b. Connect tachometer to
engine.

c.
Warm
up
engine
and stabilize temperatures.

d.
Adjust
engine
idle to
speed
desired, using throt­
tle idle
speed
adjusting screw.

e.
Carburetors without Idle
Limiter
Cap turn idle mixture screws out (counterclockwise) until a
loss

of
engine
speed
is indicated; then, slowly turn mix­
ture screw in (clockwise-leaner) until maximum

speed
(RPM) is reached. Continue turning in (clockwise) until
speed
begins
to drop; turn mixture
adjustment back out (counterclockwise-richer) un­

til
maximum
speed
is just regained at a "lean as
possible" mixture adjustment.

Fl-14.
Distributor

Check
the distributor number for proper appli­
cation.
Check
the distributor cam dwell angle and
point condition and adjust to specifications or re­ place as required. (Specifications listed at the end
of this section)
Check
ignition timing and set at

0°
or
TDC.

Fl-15.
Anti-iackfire
Diverter Valve

The
anti-backfire valve remains closed
except
when
the throttle is closed rapidly from an
open
position.

To
check the valve for proper operation, accelerate
the
engine
in neutral, allowing the throttle to
close

rapidly.
The valve is operating satisfactorily when
no exhaust system backfire occurs. A further check
to determine whether the valve is functioning can be made by removing from the anti-backfire valve
the large
hose
Which
connects to the check valve.
Accelerate the
engine
to allow the throttle to
close

rapidly.
The valve is operating satisfactorily if a
momentary interruption of rushing air is audible.

Fl-16.
Check Valve

The
check valve prevents the reverse flow of ex­
haust
gases
to the pump in the
event
the pump
should, for any reason,
become
inoperative or should exhaust pressure ever
exceed
pump pressure.

To
check this valve for proper operation, remove the air supply
hose
from the pump at the
distri­

bution manifold.
With
the
engine
running, listen for exhaust leakage at the check valve which is
connected to the distribution manifold.

Fl-17.
Air
Pump

Check
for proper drive belt tension with belt tension
gauge
W-283. The belt strand tension should be

50-60
pounds on a belt with previous service, meas­

ured
on the
longest
accessible span
between
two pulleys. When installing a new belt, adjust the
tension to
60-80
pounds tension. DO NOT PRY
ON
THE DIE
CAST
PUMP
HOUSING.

To
check the pump for proper operation, remove the air
outlet
hose
at the pump.
With
the
engine

running,
air discharge should be
felt
at the pump

outlet
opening. The pump
outlet
air pressure, as determined by the relief valve, is preset and is not
adjustable.

The
air pump
rear
cover assembly, housing the pressed in inlet and discharge tubes, and the pres­
sure relief valve are the only pump
components

recommended for service replacement. These parts
are
to be replaced only when damaged as a result
of handling or in the
event
the relief valve was
tampered with.

Fl-18.
Carburetor
Air
Cleaner

Every
6000
miles
[9,600
km.] clean the inside
sur­

face at the sump and
refill
to indicated oil level with
SAE
40 or 50
engine
oil
above
32 F; SAE 20

below
32 F. Wash filter
element
in kerosene and

drain.
Reassemble the air cleaner.

More
frequent cleaning and replacement is advis­ able when the car is operated in dusty areas or on
unpaved roads. Accumulated dirt restricts air flow,
reducing fuel
economy
and performance.

Fl-19.
REMOVAL
PROCEDURES

The
following paragraphs
give
the procedures for removing the major units of the Exhaust Emission

Control
System and the required equipment
needed.

Fl-20.
Air
Pump

Loosen
the air pump adjusting strap to facilitate

drive
belt removal. Remove the air pump air dis­
charge hose(s) and air filter attachment. Separate
the air pump from its mounting bracket. At time of installation, torque tighten the air pump mount­ing
bolts
to
30-40
lbs-ft. [4,15 a 5,53 kg-m.]. Adjust
the belt strand tension to
50-60
pounds on a belt
with previous service and
60-80
pounds on a new
belt.

Fl-21.
Anti-Backfire
Diverter Valve

The
anti-backfire diverter valve removal requires disconnecting the
hoses
and bracket to
engine
at­
taching screws.

Fl-22.
Air
Distribution
Manifold
and
Injection Tubes

In
order to remove the air distribution manifold
without bending the tubing, which could result in
fractures
or leakage, it is necessary to remove the
exhaust manifold as an assembly from the
engine.

After
the exhaust manifold assembly is removed
from
the
engine,
place the manifold in a vise and

loosen
the air distribution manifold
tube
retaining nuts at each cylinder exhaust port. Tap the injec­
tion
tubes
lightly to allow the air distribution mani­
fold to be pulled away partially from the exhaust manifold. The stainless steel injection
tubes
in the
exhaust manifold may have
become
partially fused
to the air distribution manifold and, therefore, may
require
application of heat to the joint in order to
separate. While applying heat to the joint, rotate
the injection
tubes
with pliers being careful not to
damage the
tubes
by applying excessive force.

At
time of installation, the air injection
tubes
must
be positioned into the exhaust manifold prior to
placing the exhaust manifold assembly on the en­ gine.

Note:
Two different length injection
tubes
are used.

The
shorter length injection
tubes
must be inserted into cylinders 1 and 4. 145

Fl

EXHAUST
EMISSION CONTROL SYSTEMS The
air distribution manifold should be installed
after the exhaust manifold assembly is torqued
to the cylinder head. The recommended procedure
for exhaust manifold assembly installation is as follows:
Clean
the mating surface of both the
manifold and cylinder head.
Install
the exhaust manifold to the cylinder head using a new gasket.

Tighten
the manifold to cylinder head, attaching
bolts
down evenly.
Finish
torque tightening to 29
to 35 ft. lbs. [3,4 a 4,8 kg-m.].

Fl-23.
REQUIRED
EQUIPMENT

Each
station licensed to perform repair and main­
tenance on the Exhaust Emission Control System
must be equipped with that equipment necessary
for major
engine
tune-up analysis which shall in­ clude at least the following or equivalent.
Ignition Analyzer Oscilloscope
Ammeter
Ohmmeter
Voltmeter Tachometer
2 Vacuum Gages

Pressure
Gage (0-10 psi.)

Cam
Angle Dwell Meter Ignition Timing
Light

Engine
Exhaust Combustion Analyzer Compression Tester

Fl-24.
REPLACEMENT
PARTS

Parts
necessary to repair and/or maintain the

Exhaust
Emission Control System are available through any Jeep
SALES CORPORATION
ware­
house.

Fl-25.
WARRANTY

All
parts of the Exhaust Emission Control System

are
covered by the Manufacturer's Warranty as stated in the Warranty Service and 'Jeep' Quality
Maintenance Plan booklet.

Fl-26.
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 also desirable to
allow for normal break-in wear of the pump prior
to replacement for excessive noise.

Pump Seized

Replace
pump.

Leak
In
Hose

Check
for leaks; using
soap
and water — tighten
clamps or replace
hoses.
Pump
Inoperative

Loose Belt — tighten belt — do not pry on housing.

Filter
Plugged — replace.

Exhaust Backfire

Check
for vacuum leaks — correct as necessary.
Check
air filter for excessive
restriction
— replace as necessary.

Check
anti-backfire valve — replace as necessary.

Induction System Backfire

Verify
engine
timing and distributor dwell.

Verify
accelerator pump charge. 146

'Jeep'
UNIVERSAL SERIES
SERVICE
MANUAL

Fl
Fl-27.
EXHAUST EMISSION CONTROL SYSTEM MAINTENANCE CHART

Efficient
performance of the Exhaust Emission
Control
System is
dependent
upon precise main­tenance. As indicated in the following chart, it is very important that all of the maintenance require­

ments
listed are performed with extreme care at
the specific intervals indicated.

OPERATION
Thousands of miles* or
number of months whichever
occurs first 2
6
12 18
24 30

R R
R R
R R

O O o O
O
o O

R
O
o
o

R
o

o o

o
o

o
O
o
Inspect engine-driven
belts
for condition and tension...
Replace positive crankcase ventilation valve (PCV) Replace filter on exhaust emission control system

Clean
carburetor air cleaner

Engine
tune-up
Check
engine
timing

Adjust
carburetor idle
speed
and mixture

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

R
— Required Services
O
— Optional Services
Miles
2,000

6,000

12,000
18,000
24,000
30,000
Kilometers

3,200

9,600

19,200
28,800
38,400 48,000

Fl-28.
EXHAUST EMISSION CONTROL SYSTEM CARBURETOR SPECIFICATIONS

Make
Models

Part
Number
Throttle
Bore
Main
Venturi

Low
Speed Jet

Main
Metering Jet

Idle
Port
Nozzle Bleed in Body
Pump Jet

Float
Level
Dash
Pot Setting

Engine
Idle
RPM:
with Distributor Model
IAY-4401A.
with Distributor Model
IAY-4401B.
Carter
— Single Bore

^ an H
YF
4366S ana 4941S, 6115S

1M"
[3,81 cm.]

IX"
[3,18 cm.]
.035"
[0,889
mm.] .089" [2,26 mm.]
.184" x .030" [4,70 a
0,765]
.028"
[0,713
mm.]
.024"
[0,610
mm.] lW [6,74 mm.]
%"
[3,75 mm.] 650 — 700 700 — 750

Fl-29.
EXHAUST EMISSION CONTROL SYSTEM DISTRIBUTOR SPECIFICATIONS

Engine

Make
Models
Rotation
Point Opening

Breaker
Lever
Tension..
Cam
Angle (Dwell)
Condenser Capacity
Dist.
Degrees and RPM:
Start..

Intermediate

Maximum

TIMING:
Crankshaft

Mark
Location

Firing
Order
F4-134
Prestolite

IAY-4401A

CCW
Rotor End
.020"
[0,508
mm.|
17 — 20 ozs. [482 a 567 gr.l
42°

.25 — .28 mfd.

0°
— 300
3°
— 375

13.5°
— 1700

0°
TDC @ Idle

Crankshaft
Pulley
1-3-4-2
Prestolite

IAY-4401B

CCW
Rotor End
.020"
[0,508
mm.]
17 — 20 ozs. [482 a 567 gr.
42°

.25 — .28 mfd.

0°
— 450

4.5°
— 550

13.5°
— 1700

0°
TDC @ Idle

Crankshaft
Pulley
1-3-4-2

Fl-30.
SPARK PLUG
GAP

Spark
Plug Gap. .030"
[0,765
mm.] 147

'Jeep'
UNIVERSAL SERIES SERVICE
MANUAL

Fl
EXHAUST
EMISSION
CONTROL
SYSTEM

Contents

DAUNTLESS
V-6
ENGINE
SUBJECT
PAR.

GENERAL
.F2-1
HEATED
AIR
SYSTEM.
. F2-2
Testing
Thermo
Air
Cleaner
F2-4
Positive
Crankcase
Ventilation
Valve.
. . .F2-6

Vacuum
Motor Replacement . .F2-8
Air
Cleaner Sensor Replacement F2-9
Replacement Procedures F2-7

AIR
PUMP
.F2-10

AIR
FILTER.
F2-11

AIR
DELIVERY
MANIFOLD.
F2-12

AIR INJECTION TUBES.
F2-13

ANTI-BACKFIRE
VALVE..
.F2-14
ENGINE COMPONENTS
.F2-15
MAINTENANCE
.F2-3
Carburetor
F2-16, F2-17

Distributor
F2-18

Anti-Backfire
Valve . . F2-19
Check
Valve..
F2-20

F2-1.
GENERAL
—V-6
Engine

The
Dauntless V-6
engine
Exhaust
Emission
Con­

trol
System consists of a belt-driven air pump

which
directs compressed air through connecting
hoses
to a steel distribution manifold into stainless steel injection
tubes
in the exhaust port adjacent
to each exhaust valve.
This
air, with its normal
oxygen
content, reacts with the hot but incom­
pletely burned exhaust
gases
and permits further combustion in the exhaust port or manifold.

The
Exhaust
Emission System on V6-225
engines

limits
the hydrocarbon and carbonmonoxide emis­sions from the exhaust system. The system includes

an
engine
designed for low emissions and lean
carburetor
calibration at idle and part throttle.

The
lean carburetion is possible because of the
heated air system that is part of the Emission
System.
See Fig. F2-2.
With
the heated air system
operating, inlet air temperature is around
115°F.
[46°C],
after the first few minutes of operation.

This
makes the use of lean (hot weather)
cali­
bration
possible, and the vehicle
still
responds and

drives
well in cold weather.

The
engine
has a "ported"
spark
advance, with the

vacuum
take-off just above the throttle valve, so that there is no vacuum advance at closed throttle,
but there is vacuum advance as
soon
as the throttle is opened slightly. To reduce emissions at idle and
at lower
engine
speeds, the
engine
timing is such
that the distributor
will
not have centrifugal ad­
vance until about 900 RPM.
F2-2.
HEATED
AIR
SYSTEM

The
heated air system on late model V6 engines,
consists of a manifold heat collector, a heated-air
SUBJECT
PAR.

Air
Pump F2-21
Intake
Manifold F2-22
Carburetor
Air Cleaner F2-5, F2-23

REMOVAL PROCEDURES
F2-24
Air
Pump. F2-25
Anti-Backfire
Valve..
. . .F2-26
Air
Distribution Manifold,

And
Air Injection Tubes F2-27

REQUIRED
EQUIPMENT..
. F2-28
REPLACEMENT
PARTS..
.F2-29

WARRANTY
F2-30
DIAGNOSIS GUIDE
F2-31
MAINTENANCE CHART.
F2-32
GENERAL
SPECIFICATIONS
F2-33

CARBURETOR SPECIFICATIONS.
.... .F2-34

DISTRIBUTOR SPECIFICATIONS
. .F2-35
SPARK PLUG GAP
F2-36
pipe, a adapter elbow and an air cleaner contain­ing temperature control doors operated by vacuum
through a temperature sensor. The heat
stove
is a
sheet
metal cover, shaped to and bolted on with
the right exhaust manifold. Air drawn in along the lower
edge
of the
stove
passes across the mani­
fold surface, picking-up heat. The heated air is
drawn
out from the front of the manifold, through
the heated air pipe and adapter elbow into the
snorkel
of the air cleaner.

The
temperature control air cleaner is designed to mix this heated air with cold air from under the
hood so that carburetor inlet air temperature aver­
ages
about
115°F.
[46°C.].
This
mixing is
done
by two air doors, a cold air door and a hot air door,

which
move
together
so that when the cold air door is closed, the hot air door is open and vice
versa.
Most of the time, both doors
will
be partially
open as required to control the temperature. When
the underhood temperature reaches about 135
°F
[57°C]
the cold air door
will
open wide and the
hot air door
will
close
tight See Fig. F2-3. Ob­ viously, if underhood temperatures rise above
135°F.
[57°C]
the air cleaner
will
no longer be
able to control temperatures and the inlet air tem­

perature
will
rise with underhood temperature.
The
temperature doors are moved by a diaphragm
type vacuum door. When there is no vacuum pres­ ent in the motor, the diaphragm spring forces the
cold air door open and the hot air door closed.

Whenever
the
engine
is running, the amount of
vacuum
present in the vacuum motor depends on
the temperature sensor in the air cleaner which is located in the vacuum line
between
the intake
manifold and the vacuum motor. In the sensor, a 149

F2
EXHAUST EMISSION CONTROL SYSTEMS
the throttle
stop
screw to idle the
engine
at 650
to 700 rpm.

F2-17. Carburetor Idle Setting
The
"Lean
Best
Idle"
Method of Idle Setting is as
follows:

a.
Any scheduled service of ignition system should
precede this adjustment

b.
Connect tachometer to engine.

c.
Warm
up
engine
and stabilize temperatures.

d.
Adjust
engine
idle to speed desired, using throt­
tle idle speed adjusting screw.
e.
Turn
idle mixture screws out (counterclockwise)

until
a
loss
of
engine
speed is indicated; then slowly
turn
mixture screws in (clockwise-leaner)
until
maximum speed (rpm) is reached. Continue

turning
in (clockwise) until speed begins to drop;

turn
mixture adjustment back out (counterclock­
wise-richer)
until maximum speed is just regained

at
a "lean as possible" mixture adjustment.

F2-18. Distributor
The
ignition distributor used with the
Exhaust
Emission
Control
System is the same as that used
on
engines
without
Exhaust
Emission
Control.
Check
the distributor cam dwell angle and point
condition.
Check
ignition timing and adjust to specifications shown on the last
page
of this section.

F2-19.
Anti-Backfire
Valve

The
anti-backfire valve remains closed except when
the throttle is closed rapidly from an open position.
To
check the valve for proper operation, accelerate
the
engine
in neutral, allowing the throttle to close

rapidly.
The valve is operating satisfactorily when
no exhaust system backfire occurs. A further check
to determine whether the valve is functioning can
be made by removing from the anti-backfire valve
the large
hose
which connects the valve to the

pump.
With
a finger placed over the open end of
the
hose
(not the valve), accelerate the
engine
and allow the throttle to close rapidly. The valve is
operating satisfactorily if a momentary air rushing
noise is audible.

F2-20.
Check
Valve

The
check valves in the lines to the air distribution manifolds prevent the reverse flow of exhaust
gases

to the pump in the event the pump should, for

any
reason,
become
inoperative or should exhaust

pressure
ever exceed pump pressure.

To
check this valve for proper operation, remove the air supply
hose
from the pump at the check

valve.
With
the
engine
running, listen for exhaust
leakage at the check valve which is connected to
the distribution manifold.

F2-21.
Air
Pump

Check
for proper drive belt tension with belt tension
gauge
W-283. The belt strand tension should be 60 pounds measured on the
longest
accessible span
between two pulleys. DO NOT PRY ON THE

DIE
CAST
PUMP
HOUSING. To
check the pump for proper operation, remove
the air
outlet
hose
at the pump.
With
the
engine

running,
air discharge should be felt at one of
the pump
outlet
openings. The pump
outlet
air
pressure,
as determined by the relief valve, is preset
and
is not adjustable.

The
air pump
rear
cover assembly, housing the pressed in inlet and discharge tubes, and the pres­
sure
relief valve are the only pump components
recommended for service replacement. These parts
are
to be replaced only when damaged as a result
of handling or in the event the relief valve was
tampered with.

F2-22.
Intake Manifold

Intake
manifold leaks must not be overlooked. Air
leakage at the intake manifold may be compen­
sated for by
richer
idle mixture setting, however, this
will
usually cause uneven fuel-air distribution
and
will
always result in
loss
of performance and
exhaust emission control. To check for air leakage
into the intake manifold, apply kerosene or naph­
tha,
on the intake manifold to cylinder head joints

and
observe whether any changes in
engine
rpm

occur.
If an air leak is indicated, check the mani­
fold to cylinder head bolt torque. The correct torque is 25-35 lbs. ft. [3,46 a 4,84 kg-m.]. If the

leak
is
still
evident,
loosen
the manifold assembly

and
torque-tighten the bolts evenly.
Start
from the center and use proper torque values. Replace the
manifold
gasket if the leak
still
exists.
Clean
both
mating surfaces and check for
burrs
or other ir­

regularities.

Always
torque the bolts evenly to the specified
torque value to prevent warpage.

F2-23.
Carburetor
Air
Cleaner
—Oil
Bath

Every
6,000
miles [9,600 km.] disconnect attach­

ing
hoses
and unscrew the wing nut from the top
of the air cleaner and lift it off the carburetor.

Lift
the cover and filter element off the oil sump.

Clean
the inside surface of the sump and
refill
to

indicated
oil level with SAE 40 or 50
engine
oil
above 32 F; SAE 20 below 32 F.
Wash
filter element in kerosene and
drain.
Reassemble the air

cleaner
and install on carburetor.

More
frequent cleaning and replacement are advis­ able when the car is operated in dusty areas or on

unpaved
roads. Accumulated
dirt
restricts air flow,
reducing
fuel economy and performance.

F2-24.
REMOVAL PROCEDURES
The
following paragraphs
give
the procedures for removing the major units of the exhaust emission
control
system and the required equipment needed.

F2-2S.
Air
Pump

Loosen
the air pump mounting bracket bolts. Re­ move the air pump air hose(s). Separate the air pump from its mounting bracket. At time of install­
ation,
torque tighten the air pump mounting bolts
to
30-40
lbs.-ft [4,15 a 5,53 kg-m.].
Adjust
the
belt strand tension to 60 pounds. 156

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