1953 JEEP DJ length

Dl

DAUNTLESS
V-6
ENGINE
Dl-38.
Crankshaft
Cleaning

Clean
the crankshaft thoroughly with a suitable
cleaning solvent.
Clean
drilled oil
passages
in its

journals
with a small rifle brush to remove all
sludge
or gum deposits; dry
passages
with com­
pressed air.

Dl-39.
Crankshaft
Inspection
and
Repair

If
the crankshaft has not
been
removed from the

cylinder
block for inspection, disconnect two con­ necting rods at a time from crankshaft. Inspect
the bearings and crankpin journals. While turning
crankshaft,
it is necessary to temporarily reconnect
the rods to crankshaft to avoid possibility of dam­ aging the journals through contact with uncon­
nected rods.
Inspect the crankpins visually for excessive or ir­

regular
wear, and for scoring. Use an
outside
micrometer to check crankpins for out-of-round.
Standard
crankpin
diameter is
2.0000"
[5,080
cm.].

If
crankpins are more than .0015"
[0,0381
mm.]
out-of-round, new bearings cannot be
expected
to
have satisfactory life.
If
the crankshaft has
been
removed from the
cyl­

inder
block for inspection support it on V-blocks
at its main bearing journals 1 and 4. Inspect the

main
bearing journals visually for excessive or ir­

regular
wear, and for scoring. Standard main bear­
ing
journal
diameter is 2.4995"
[6,349
cm.].
Total

indicator readings at each
journal
should not ex­
ceed .003"
[0,076
mm.].

Check
run out at all four journals and
note
high
spot
(maximum eccentricity) of each
journal.
High

spot
of each
journal
should
come
at the same
angular
location. If high
spots
do not coincide,

crankshaft
is misaligned and unsatisfactory for
service.

If
crankpin or main bearing journals are scored,
ridged, or out-of-round, the crankshaft must be replaced or reground to a standard undersize bear­
ing diameter to ensure satisfactory life of bearings. Slight roughness can be removed with a fine grit
polishing cloth thoroughly
wetted
with
engine
oil.
Burrs
can
be
honed with a fine oil
stone,
so long as
bearing clearances
will
remain within specified
limits.

Dl-40.
Crankshaft
Main
Bearings

A
crankshaft bearing consists of two halves which
are
neither alike nor interchangeable. One half is

carried
in the corresponding main bearing cap; the
other half is located
between
the crankshaft and

cylinder
block. The upper (cylinder block) half
of the bearing is grooved to supply oil to the con­ necting rod bearings, while the lower (bearing cap)

half
of the bearing is not grooved. The two bearing
halves must not be interchanged. All crankshaft
bearings
except
the thrust bearing and the
rear

main
bearing are identical. The thrust bearing (No. 2) is longer and it is flanged to take
crank­

shaft end thrust. When the bearing halves are
placed in cylinder block and bearing cap, the
ends
extend slightly beyond the parting surfaces. When
cap
bolts
are tightened, the halves are clamped
tightly in place to ensure positive seating and to
prevent turning. The
ends
of bearing halves must never be filed flush with parting surface of
crank­

case or bearing cap.

Crankshaft
bearings are the precision type which
do not require reaming to size or other fitting.
Shims
are not provided for adjustment since worn
bearings are readily replaced with new bearings of proper size. Bearings for service replacement are

furnished
in standard size and undersizes. Under no circumstances should crankshaft bearing caps
be filed to adjust for wear in old bearings.

Dl-41.
Crankshaft
Main
Bearing
Cleaning
and
Inspection

Clean
main bearing surfaces. Inspect the bearings

visually
for excessive or uneven wear, scoring, and

flaking.
Visibly worn or damaged bearings must
be replaced. It is necessary to check
radial
clear­ ance of each new or used crankshaft main bearing
before installation.
This
can be
done
by either of two methods, which are described in
Pars.
Dl-42

and
Dl-43.

a.
The desired
radial
clearance of a new bearing
is .0005" to .0021"
[0,0127
a
0,0534
mm.].
b. Replacement bearings are furnished in standard
size, and in several undersizes, including undersizes
for reground journals. If a new bearing is to be installed, try a standard size; then try each under­
size in turn until one is found that
meets
the
specified clearance limits.

Note:
Each
undersize bearing half has a number
stamped on its outer surface to indicate amount of undersize. Refer to Fig. Dl-12. 14288

FIG.
Dl-12—LOCATION
OF
UNDERSIZE
MARK
ON
BEARING
SHELL

1—
Tang

2—
Undersize
Mark
Dl-42.
Main
Bearing
Fitting,
Plastigage

Bearing
clearance can be checked by use of Plasti­
gage,
Type PG-1 (green) which has a range of
.001" to .003" [0,025 a
0,076
mm.]. Refer to

Fig.
Dl-13.

a.
Place a piece of Plastigage lengthwise along the
bottom
center of the lower bearing half, then 86

Dl

DAUNTLESS
V-6
ENGINE

FIG.
D1-28—CLEANING
OR
ENLARGING
VALVE
GUIDE

1—Reamer
d.
Measure clearance of each valve stem in cor­
responding valve guide. For intake valves, this
clearance
should be .0012" to .0032" [0,0305 a

0,0813
mm.]. For exhaust valves, this clearance should be .0015" to .0035"
[0,0381
a
0,0889
mm.]
at top of guide and .002" to .004"
[0,051
a 0,102 mm.] at bottom of guide. If this clearance is exces­
sive, valve guides must be reamed with .004" [0,102 mm.] oversized reamer J-5830-1 and valves

replaced
by new valves with oversize stems.

Dl-63.
Cylinder
Head
and Valve
Repair
a.
If a valve stem has excessive clearance in its
guide, the guide must be reamed .004" [0,102 mm.]
oversize. Valves are available with oversize stems
to fit this valve guide diameter.

b.
Grind
valve faces or replace valves if necessary.

Valve
faces must be ground at an angle of 45 degrees. If a valve head must be ground to a
knife
edge
to obtain a true face, the valve should
be replaced.

c.
If necessary, grind valve seats at an angle of 45 degrees.
Grinding
a valve seat decreases valve
spring
pressure and increases the width of the seat.

The
nominal width of the valve seat is
[
1,59
mm.].
If a valve seat is wider than %" [1,98 mm.]
after grinding, it should be narrowed to specified

width
by the use of 20-degree and 70-degree stones.
Improper
operation of a hydraulic valve lifter may

result
if valve and seat are refinished to the extent
that the valve stem is raised more than .050" [1,27 mm.] above normal height. In this case, it
is necessary to grind off the end of the valve stetti or replace parts.

Note:
The normal height of the valve stem above
the valve spring seat surface of the head is
1.925"
[4,889 cm.].

d.
Lightly
lap the valves into seats with fine grind­
ing compound. The refacing and reseating should
leave the refinished surfaces smooth and true so that a minimum of lapping
will
be required. Ex­
cessive lapping
will
groove the valve face and pre­
vent
good
valve seating.
e. Test valve seats for concentricity with guides,
and
for proper valve seating. Coat a small segment
of the valve face lightly with Prussian blue pig­ ment.. Insert the valve stem into its guide and

turn
the valve face against the seat. If the valve seat is concentric with the valve guide, a
mark

will
be made all around the seat. If the seat is not concentric with the guide, a
mark
will
be made
on only one side of the seat.

Clean
all pigment from both valve and seat. .Next,
coat a small segment of the valve seat lightly with

Prussian
blue pigment. Again insert the valve stem into its guide and rotate the valve face against the
seat. If the valve face is concentric with the valve
stem, and if the valve is seating all the way around,
pigment
will
coat the valve face with a uniform
band
around its entire perimeter. Both of
these

tests
are necessary to prove that proper valve seat­
ing is obtained.
f. Inspect the valve springs visually for corrosion,

breaks,
and distortion.
With
a valve spring tester
check
each valve spring for proper tension. When

a
valve spring is compressed to a length of
1.640"
[4,166 cm.] (closed-valve condition), it should
have a tension of 64 lb. [29,03 kg.]. When a valve
spring
is compressed to a length of
1.260"
[3,200
cm.] (open-valve condition), it should have ten­ sion of 168 lb. [76,205 kg.]. Replace any valve
spring
which is visibly damaged or
does
not
meet

tension specifications.

Dl-64.
Valve Installation

Lubricate
valve stems with engine oil.
Install
valves, valve springs, spring retainers, and valve

retainers
on the cylinder head. Use the same equipment and reverse procedure used for removal.

Install
valve springs with closely wound coils to­

ward
the cylinder head. Refer to Fig. Dl-29.
FIG.
Dl-29—VALVE
SPRING

1—
Spring

2—
Close
Wound
Coils
Toward
Head
94

Dl

DAUNTLESS
V-6
ENGINE
Note:
During
engine
reassembly, use Perfect Seal

Aerosol
Spray Sealer
Part
No.
994757
on all en­
gine
gaskets to ensure against vacuum, oil, gasoline

and
water leaks. Apply to head gaskets, valve covers, water pumps, oil pan gaskets, radiator and
heater
hose
connections, felt gaskets, gasoline and
oil
line connections, stud bolts, spark plug threads,

and
grease retainer washers. Refer to manufac­
turer's
instructions on container for proper appli­
cation procedure.

Dl-72.
Cylinder
Block
and Crankshaft
Rear
Oil Seals

Braided
fabric seals are pressed into
grooves
of
cylinder
block and
rear
main bearing cap, to
rear

of the oil collecting groove, to seal against oil leak­ age at the crankshaft. Refer to Fig. Dl-32.

FIG.
Dl-32—INSTALLING
CRANKSHAFT REAR
OIL
SEAL

1—Neoprene
Seal
2—Fabric
Seal

A
neoprene composition (stick) seal is installed in
grooves
in the sides of the
rear
main bearing cap
to seal against leakage in the joints
between
the
cap and cylinder block. The neoprene composition
expands in the presence of oil and heat.
This
seal
is undersize when newly installed. Refer to Fig.

Dl-32.

a.
The braided fabric seal can be installed in the

cylinder
block only when the crankshaft is re­ moved; however, the seal in the cap can be replaced
whenever the cap is removed. Remove oil seal and place new seal in groove, with both ends projecting
above parting surface of cap. Force seal into
groove

by rubbing down with hammer handle or smooth
stick
until seal projects above the
groove
not more

than
[1,59 mm.]. Cut ends off flush with
sur­

face of cap, using sharp knife or razor blade.
Lubricate
the seal with heavy
engine
oil just before
installation.

Caution:
The
engine
must be operated at slow
speed when first started after new braided seal
has been installed.
b. The neoprene composition seal is slightly longer

than
the
grooves
in the bearing cap. The seal must
not be cut to length. The seals are installed after the bearing cap is installed in the block and torqued
firmly
in place. Dip the neoprene seals in kerosene
approximately IV2 minutes, then install seals into
bearing cap grooves. The protruding ends of the seals are, again, squirted with kerosene, wiped off,

and
peaned over with a hammer to be sure of a
seal
at the upper parting line
between
the cap and

cylinder
block.

Dl-73.
Main
Bearing and Crankshaft
Installation

Refer
to Fig. Dl-6.

This
procedure assumes that crankshaft main bear­
ings have been inspected and proven satisfactory,

or
that new crankshaft main bearings of appropriate size have been selected. If necessary, check or select
main
bearings as described in Par. Dl-41 and
Pars.

Dl-42 and Dl-43.

a.
Install
four upper main bearing halves in
seats

of cylinder block so that prong of each bearing half
fits into corresponding notch of seat. Flanged thrust
bearing must be installed in the second seat from
front of engine.
Install
a new upper crankshaft
rear
oil seal in the cylinder block as described in

Par.
Dl-72.

Caution:
Upper main bearing halves have an oil groove, while lower halves are plain. They must
not be interchanged.
b. Apply
engine
oil to upper bearing surfaces.

Install
the crankshaft so that its four journals rest

in
the upper bearing halves.
c. Seat all four lower main bearing halves in cor­
responding bearing caps.
Install
a new lower
crank­

shaft
rear
oil seal and cylinder block
rear
oil seal
described in
Par.
Dl-72, a and b.
Lubricate
all lower

main
bearing surfaces with
engine
oil. Position bear­ ing caps to cylinder block and crankcase journals.

Install
two cap bolts,
loosely,
at each cap.

d.
It is necessary to align thrust surfaces of the
second main bearing whenever it has been removed

from
the engine. To do this, pry the crankshaft

back
and forth several times, throughout its entire end travel, with cap
bolts
of second main bearing
only finger tight.
e. Tighten alternate cap
bolts
of each main bearing

cap,
a little at a time, until they have been tight­ ened to 80 to 110 lb-ft. [11,1 a 15,2 kg-m.] torque.
D1-74. Crankshaft End Play Check

To
measure crankshaft end play, mount a dial
indicator
on the cylinder block and index its plung­

er
to either a front or
rear
face of one crankshaft
counterweight. Pry the crankshaft to one limit
of its end travel and adjust the dial indicator to
zero. Pry the crankshaft to its
opposite
end travel

limit
and
note
end play as indicated by the dial

indicator.
Crankshaft end play tolerances are .004"
to .008" [0,102 a
0,204
mm.]. If end play is too great, it can be corrected only by replacement of
the second main (thrust) bearing.

Dl-75.
Piston and Connecting Rod
Installation

This
procedure assumes that connecting rod bear­ ings have been inspected and proven satisfactory,

or
that new connecting rod bearings of appropriate 96

Dl

DAUNTLESS
V-6
ENGINE
E-105.
DAUNTLESS V-6 ENGINE SPECIFICATIONS

ENGINE:
Type

Number
of Cylinders Valve Arrangement
Bore
Stroke

Piston
Displacement

Firing
Order Compression Ratio

Number
of
Mounting
Points:

Front.

Horsepower
(SAE)

Horsepower
(max. brake) Torque (max.
2400
rpm.)
Cylinder
Numbers,
Front to Rear:
Right Bank

Left
Bank
Cylinder Block Material
Cylinder Head Material English

90°
V-6 6

In
head
3.750"
3.400"

225 cu. in.
1.6.5.4.3.2

*9.0:1

2

33.748

160 @
4200
rpm. 235
lb-ft.

2, 4, 6 1, 3, 5

Cast
Iron
Cast
Iron Metric

9,525
cm.

8,636
cm. 3,69 ltr.

32,49
kg-m.

PISTONS:
Material
Description Clearance Limits:
Top
Land
Skirt
Top

Skirt
Bottom

Ring Groove Depth*. No. 1
No. 2, 3
Cylinder Bore: Out-of-Round (max.). Taper (max.)
Cast
Aluminum Alloy

Cam
Ground, Tin Plated

.0125"
to
.0295" .0005"
to
.0011"

.0005"
to
.0011"

.1880"
to
.1995"
.1905"
to
.1980"

.003"
.005" 0,318 a
0,749
mm.

0,0127
a
0,0279
mm.

0,0127
a
0,0279
mm.

4,775
a
5,067
mm.
4,839
a
5,029
mm.

0,076
mm. 0,127 mm.

PISTON
RINGS:
Function: No. 1 and No. 2 Ring.. No. 3 Ring
Location
Material: No. 1...
No. 2 No. 3.

Oil
Ring Type
Oil
Ring Expander
Width: No. 1
No. 2. .
No. 3

Gap:
No. 1 and No. 2
No. 3

Side
Clearance in Groove: No. 1
No. 2
No. 3 Compression

Oil
Control

Above
Piston
Pin

Iron,
Chrome Plated
Iron,
Pre lubricated
Steel

Dual
Rail,
With Spacer Humped Ring

.0785"
to
.0790" .0770"
to
.0780"
.181" to .187"
.010" to .020"
.015" to .035"
.002" to
.0035"
.003" to .005"

.0015"
to
.0085"
1,993 a
2,007
mm.
1,956 a 1,981 mm. 4,60 a 4,75 mm.
0,25 a 0,51 mm.
0,38 a 0,89 mm.
0,051 a
0,089
mm.
0,076
a 0,127 mm.

0,038
a
0,220
mm.

PISTON
PINS:
Material
Length

Diameter

Type Clearance in
Piston

Clearance in
Connecting
Rod.

Distance
Offset
Toward High-Thrust
Side
of Piston.
Steel,
SAE 1018, SAE 1118

3.060"

.9394"
to
.9397"

Pressed in
Connecting
Rod
.0004"
to
.0007" .0007"
to
.0017"

.040"
7,772
cm.

23,861
a
23,868
mm.

0,0102
a
0,0178
mm.
0,0178
a
0,0431
mm.
1,016 mm.
*State
of California Exhaust Emission Control Engine 7.4 Compression Ratio.
106

'Jeep*
UNIVERSAL
SERIES
SERVICE
MANUAL

Dl
Dl-105.
DAUNTLESS
V-6
ENGINE
SPECIFICATIONS—Continued

CONNECTING
RODS:
Material
Installation
Bearings: Type........
Material.
Length Clearance

End
Play
(total
for two
connecting
rods)

CRANKSHAFT:
Material ,

End
Thrust
End
Play

Main
Bearings: Number Type
Material:
Length, Over-All: No. 1, No. 3, and No. 4
No. 2
Clearance

Main
Journal Diameter.
Crankpin
Journal Diameter
Flywheel Run Out, max

CAMSHAFT:
Material
Bearings: Number Material Clearance

Journal
Diameter: No. 1 No. 2
No. 3.
No. 4
Location Camshaft Drive

Chain
Links
Camshaft Sprocket Material
Crankshaft Sprocket Material

VALVE
SYSTEM:
Valve Lifters Diameter Clearance in Cylinder Block
Leak-down Time
(seconds)

Rocker Arms: Ratio Clearance on Shaft
Valves: Intake: Material
Head Diameter

Seat
Angle
Stem
Diameter

Stem
Clearance in Guide
Exhaust:
Material Head Diameter

Seat
Angle
Stem
Diameter

Stem
Clearance in Guide
Valve Springs — Pressure at Length: Valve Closed English
Pearlitic Malleable Iron

From
Top of Cylinder Bore
Removable, Steel-Backed Aluminum .737"

.0020"
to
.0023"
.006" to .014" Metric
18,72 mm.

0,0508
a
0,0584
mm. 0,153 a
0,356
mm.
Pearlitic Malleable Iron
Second
Main Bearing .004" to .008"

Removable

Moraine 100
.864"

1.057"

.0005"
to
.0021"
2.4995"

2.0000"

.015" 0,102 a
0,203
mm.
21,95 mm.

2,685
cm.

0,0127
a
0,0533
mm.
6,349
cm.
5,080
cm.
0,381 cm.

Cast
Iron Alloy
Steel-Backed Babbitt
.0015"
to
.0040"

1.755"
to
1.756"

1.725"
to
1.726"

1.695"
to
1.696"

1.665"
to
1.666"

In
Cylinder Block, at Center of V
Chain
and Sprocket 54
Aluminum,
Nylon
Coated Sintered Iron
0,0381
a
0,1016
mm.

4,458
a
4,460
cm.
4,382
a
4,384
cm.
4,305
a
4,307
cm.

4,229
a 4,231 cm.
Hydraulic

.8422"
to
.8427"

.0015"
to
.0030"
12 to 60
1.6:1

.0017"
to
.0032"

Steel,
SAE 1041
1.625"
45°

.3415"
to
.3427"
.0012"
to
.0032"

GM-N82152
(21-4N)
1.3750"
45°

.3402"
to
.3412"
.3397"
to
.3407"

.0015"
to
.0035"
(top)
.002" to .004"
(bottom)

1.640"
at 59 - 64 lb.
1.260"
at 168 lb. 21,39 a 21,40 mm.

0,0381
a
0,0762
mm.

0,0432
a
0,0812
mm. 4,128 cm.

8,674
a
8,704
mm.

3,4925
cm.
8,641 a
8,666
mm.

8,628
a
8,653
mm.

0,0381
a
0,0889
mm. 0,051 a 0,102 mm.
4,16 cm. at
26,76
-
29,03
kg. 3,20 cm. at
76,20
kg.
107

'Jeep'
UNIVERSAL SERIES SERVICE
MANUAL

E
possibility of vapor lock by keeping cool fuel from
the tank constantly circulating through the fuel
pump.

Fuel
pump pressure at carburetor (inlet) on Daunt­
less
V6-225
engine
should be 3% lbs.
[0,264
kgm-cm2] minimum at idle with the vapor return
hose

squeezed off. With the vapor return
hose
open
pump pressure should be 2j^ lbs. [0,176 kg-cm2]
minimum.

The
Dauntless V-6
engine
is equipped with a sealed

unit,
non-repairable, single-action fuel pump (Fig.

E-33).

Note:
All Dauntless V-6
engines
are equipped with

a
throw-away can-type gasoline filter installed in
the fuel line
between
the fuel pump and the
car­
buretor.
This
unit must be replaced every
12,000
miles
[19.200
km.] of vehicle operation.

E-68.
Fuel
Pump Removal

To
remove the fuel pump from the Dauntless V-6
engine, disconnect the fuel inlet, fuel
outlet
and fuel return lines from the pump. Remove the two
fuel pump body attaching cap screws and lock

washers.
Pull
the fuel filter bracket free and remove the pump and gasket. Discard pump and gasket.
Install
new pump in reverse procedure of removal.

E-69.
AIR
CLEANER

Servicing
of the air cleaner is properly taken care of as part of the periodic lubrication and servicing of the vehicle. For this reason, air cleaner servicing
information is given in the Lubrication Section.

Refer
to and follow the instructions given there.

E-70. ACCELERATOR LINKAGE
The
accelerator linkage is properly adjusted when
the vehicle leaves the factory. However, in time
components parts
will
become
worn and require re­
adjustment to maintain a smooth even control of
engine
speed. On Models equipped with F4
engines

the adjustment is made at the adjusting block,

Fig.
E-34. Loosen the lock nuts, and adjust the length of the accelerator rod so that when the
car­

buretor throttle valve is wide open the accelerator
treadle
will
just strike the toe board. After correct
adjustment is made tighten both lock nuts firmly.
To
adjust the accelerator linkage on V6
engines

loosen
the lock nuts securing the accelerator rod
housing to its securing bracket and adjust the length
of the accelerator rod so that when the carburetor throttle valve is wide open the accelerator treadle

will
just strike the toe board. After correct adjust­
ment is made, tighten lock nut firmly, see Fig. E-35 for Dauntless V-6 engine.

E-71. FUEL
TANK
AND
FUEL LINES
The
following paragraphs (E-70 through E-73) describe the removal, installation and services to
be performed when replacing the fuel tank or
servicing
the fuel system.

FIG.
E-34—ACCELERATOR LINKAGE,
F4
ENGINE
1—
Grommet

2— Nut and Lockwasher

3—
Throttle
Control
4—
Choke
Control 5—
Treadle
Rod Seal
6—
Accelerator
Treadle
7—
Treadle
Hinge Pin
8—
Treadle
Hinge 9— Nut and Lockwasher
10—
Screw

11—
Accelerator
Rod
12— Nut
13—
Adjusting
Block
14—
Retracting
Spring
15—
Cotter
Pin
16—
Lower
Beilcrank
17—
Washer

18—
Beilcrank
Link
Rod
19—
Bracket

20—
Throttle
Wire
Stop
21—
Beilcrank
Spring
22—
Rod

23—
Upper
Beilcrank
24—
Wesher
10731
131

'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

'Jeep'
UNIVERSAL
SERIES SERVICE
MANUAL

F2
F2-26.
Anti-Backfire
Valve

The
anti-backfire valve removal requires discon­ necting the
hoses
and bracket to
engine
attaching
screws.

F2-27.
Air Distribution Manifold and
Injection
Tubes

The
air distribution manifolds can be removed
from the cylinder heads without removing the

cylinder
head assemblies. Disconnect the air delivery
hose
from the pump at
the distribution manifold inlet (check valve).
Loosen the distribution manifold
tube
attaching nuts from the cylinder head and carefully work the
distribution manifold away from the cylinder head.

The
air injection
tubes
can be removed from the
cylinder
head with head on the
engine.
Insert
an easy-out through the
boss
opening on the

cylinder
head
into
the injection
tube
and twist
the
tube
out gradually. Some interference to re­ moval may be encountered due to normal carbon
build-up on the tubes. Injection
tubes
removed in
this manner should be replaced.
The
injection
tubes
used are all of the same diam­
eter and length.

F2-28.
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 Gauges
Pressure
Gauge (0-10 psi.)

Cam
Angle Dwell Meter
Ignition Timing
Light

Engine
Exhaust Combustion Analyzer Compression Tester

F2-29.
REPLACEMENT PARTS

Parts
necessary to repair and/or maintain the Ex­
haust Emission Control System are available through any Jeep
SALES
CORPORATION
ware­
house.

F2-30.
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. 157