1953 JEEP CJ tow

Dl

'Jeep5
UNIVERSAL
SERIES
SERVICE
MANUAL

FIG.
Dl-16—LEFT
BANK
PISTON

AND
ROD
ASSEMBLY
(No.
1-3-5)

1—
Oil
Spurt Hole Up
2— Boss on Rod and Cap
Rearward

3—
Notch on Piston
Forward

12716

FIG.
Dl-17—RIGHT
BANK
PISTON
AND
ROD
ASSEMBLY
(No. 2-4-6)
1—
Oil
Spurt Hole Up
2— Boss on Rod and Cap
Forward

3—
Notch on Piston
Forward

14355

FIG.
Dl-18—-PISTON
PIN
INSTALLATION
connecting rod until pin
bottoms.
Refer to Fig.

Dl-18.

e.
Remove piston and connecting rod assembly
from
press. Rotate piston on pin to be certain that

pin
was not damaged during the pressing operation. 13297
1—
Driver

2— Piston Pin

3—
Piloi
4—
Spring

5—
Collar

6—
Support
Base
FIG.
Dl-19—PISTON
RINGS

1—
Compression
Rings
2—
Expander

3—
Rail

4—
Spacer

5—
Oil
Ring
f.
Install
piston rings on piston as follows. Refer
to Fig. Dl-19. Position ends of piston ring expander
over piston pin.
Install
oil ring
rail
spacer and
oil
ring
rails.
Position
gaps
in rails upward on same
side of piston as oil spurt
hole
in connecting rod.
Install
compression rings in upper two grooves. If

a
single chrome-plated compression ring is used,
the chrome ring must be installed in the top groove.

Note:
All compression rings are marked with a
dimple, a letter
"T",
a letter
"O",
or word
"TOP"

to identify the side of the ring which must face

toward
the top of the piston. If a single chrome-
plated compression ring is used, the chrome ring must be installed in the top groove.

Dl-49.
Connecting
Rod
Bearing Inspection and Fitting

a.
If connecting rod bearings are chipped or scored,
they should be replaced. If bearings appear to be
in
good
condition, check for proper
radial
clear­
ance on crankpin. If
radial
clearance
exceeds
.003" [0,076 mm.], it is advisable to install a new

bearing.
However, if bearing appears to be in
good

condition and
does
not cause noise, it
will
not be mandatory to replace it.
Radial
clearance can be
checked either with Plastigage, as described in Par.
Dl-42,
or with a strip of feeler or shim stock, as
described in Par. Dl-43. Connecting rod bearings
differ from crankshaft main bearings in that their
desired
radial
clearance is .0002" to .0023" [0,005

a
0,0585
mm.] and their cap
bolts
and nuts are to be hand torqued to a 30 to 40 lb-ft. [4,1 a 5,5
kg-m.] torque.
b. After each connecting rod bearing has been

properly
fitted, attach bearing cap
loosely
with
two cap
bolts
and nuts to keep parts of each as­
sembly
together
until installation. 89

DAUNTLESS
V-6
ENGINE

Note:
The rib on
edge
of cap and the conical
boss

on web of connecting rod must be toward
rear
of
engine
in all connecting rod assemblies of left
cyl­

inder
bank and toward front of
engine
in all con­necting rod assemblies of right cylinder bank.

Dl-50.
Oil
Pump Intake
and
Screen Cleaning

a.
Pry screen from housing and examine for clog­
ging due to deposit of sludge or other foreign

material.

b.
Clean
the screen and housing thoroughly in sol­
vent; dry with compressed air.

c.
Install
screen in housing.

Dl-51.
Oil Pan Cleaning and Inspection

Inspect
the oil pan for corrosion, dents, leaks, and
other damage. Inspect its mounting flange carefully
for damage or distortion to be certain that it
will
give
a
good
seal.

Dl-52.
Flywheel Cleaning
and
Inspection

Clean
the flywheel with suitable cleaning solvent;

dry
with compressed air. Inspect clutch face for

burned
or scuffed condition and for rivet grooves.
Inspection
for run out or improper mounting is de­

scribed
in installation procedure.
Inspect
teeth
of the flywheel
ring
gear for
burrs,

nicks,
and minor distortion. If necessary and pos­
sible, use a small emery wheel to remove
burrs
and
reshape teeth. If gear
teeth
are broken,
cracked,

seriously
burred
or deformed, the
ring
gear must be replaced.

Dl-53.
Ring Gear Replacement

a.
Drill
a
hole
between
two
ring
gear teeth; then

split
the gear with a cold chisel. Be careful not to
damage
ring
gear shoulder or seat surfaces of fly­
wheel.

b.
Polish several
spots
on the new
ring
gear to be

installed.
With
a hot plate or slowly moving torch,
heat the new
ring
gear until polished
spots
become

blue, about
600°F.
[312°C.].

Caution:
Do not heat the
ring
gear to a temperature
greater than
800°F.
[424°C.].
Excessive heat
will

destroy heat treatment given to
ring
gear during
manufacture.

c.
Quickly
install
ring
gear on flywheel. Chamfered

edge
of
ring
gear must be toward
ring
gear shoulder
of flywheel. Be certain that
ring
gear is seated prop­

erly.
Allow
ring
gear to cool slowly, so that it
will

be held tightly in place.

Dl-54.
Flywheel Housing Cleaning and Inspection

Both
flywheel and clutch are enclosed by a fly­
wheel housing. Its front surface is bolted to the
engine
cylinder block, and its
rear
surface acts as

front
support to the transmission.
Clean
the fly­ wheel housing with a suitable cleaning solvent; dry
with
compressed air. Inspect front and
rear
surfaces
for distortion and improper alignment with each
other;
these
planes must be
parallel
to assure
proper
alignment
between
engine
and transmission.
Dl-55.
Camshaft Cleaning
and
Inspection

Clean
both camshaft and camshaft bearing surfaces

with
a suitable cleaning solvent; dry with com­
pressed air.

Note:
The steel-backed babbitt-lined camshaft
bearings are pressed into the crankcase.
From
front
to
rear,
each bearing is .030" [0,76 mm.] smaller
in
diameter than the preceding bearing.
From
front
to
rear,
each camshaft
journal
is correspondingly
smaller
in diameter.

The
camshaft bearings must be line reamed to

proper
diameter after being pressed into crankcase.
Since
this operation requires special reaming equip­
ment, the original bearings should be retained un­
less
they are severly damaged. Slightly scored cam­
shaft bearings are satisfactory if the surfaces of camshaft journals are polished, bearings are
polished to remove
burrs,
and
radial
clearance

between
camshaft and bearings is within .0015"
to .004" [0,038 a 0,102 mm.].

Dl-56.
Valve Lifter
and
Push
Rod
Cleaning and Inspection
a.
Examine the cam contact surface at lower end of each valve lifter body. If surface is excessively

worn,
galled, or otherwise damaged, discard the
valve lifter. Also examine the mating camshaft
lobe
for excessive wear or damage.

b.
Disassemble one or two valve lifters, as de­

scribed
below, and inspect them for
dirt
or
varnish.
If
they are dirty or have a varnish deposit, clean

and
inspect all twelve valve lifters. Otherwise,
service
only
those
valve lifters which do not operate

properly.

c.
To disassemble each valve lifter, depress the
push
rod seat with a push rod, and remove the
plunger retainer from the valve lifter body with

a
retainer remover. Remove push rod seat and
plunger from valve lifter body. If plunger sticks
in
valve lifter body, place body in large end of

a
plunger remover tool, with plunger downward.
While
holding lifter with thumb, rap the open end
of remover against a block of wood with just enough force to jar the plunger from body. Refer to
Figs.
Dl-20, Dl-22 and Dl-23.

d.
Drain
oil from valve lifter and remove the check
valve retainer,
ball,
valve spring, and plunger
spring.

e. Keep all parts of each valve lifter separated

during
part cleaning and inspection. The valve

lifter
body and plunger are selectively fitted to each other and must not be interchanged with parts
of other valve lifters.
f. Rinse all valve lifter parts in kerosene to remove as much oil as possible.
This
will
reduce contamina­
tion of the cleaning solvent. Immerse all parts in cleaning solvent for approximately one hour. The
time required
will
depend on varnish
deposits
and
effectiveness
of the solvent. After the varnish has
dissolved or has
softened
sufficiently to permit re­

moval
by wiping, allow parts to
drain.
Varnish
can
then be cleaned from the valve lifter body
with
a
brush.
Rinse the parts in kerosene to dissolve 90

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

'Jeep'
UNIVERSAL
SERIES SERVICE
MANUAL

Dl
size have
been
selected. If necessary, check or
select

connecting rod bearings as described in Par. Dl-49.

Note:
When a piston and connecting rod assembly
is properly installed, the oil spurt
hole
in the con­ necting rod
will
face the camshaft. The rib on the

edge
of the bearing cap
will
be on the same side
as the conical
boss
on the connecting rod web;
these
marks (rib and boss)
will
be toward the other
connecting rod on the same crankpin. The notch
on the piston
will
face the front of the
engine.

a.
Be certain that cylinder bores, pistons, connect­
ing rod bearings and crankshaft journals are absolutely clean. Coat all bearing surfaces with

engine
oil.
b. Before installing a piston and connecting rod as­
sembly into its bore, rotate the crankshaft so that
the corresponding crankpin is moved downward, away from the cylinder bore.
c. Remove bearing cap from connecting rod. With
upper bearing half seated in connecting rod, install connecting rod guides. These
guides
hold the upper
bearing half in place and prevent damage to the

crankshaft
crankpin during installation of the con­
necting rod and piston assembly.

d.
Be certain that the gap in the oil ring rails faces

upward,
toward center of
engine.
Gaps of the com­
pression rings shall not be aligned with each other

or
with the oil ring
rails.

e. Lubricate the piston and rings. Compress the
rings with a suitable piston ring compressor; install
the piston and connecting rod assembly from top of cylinder bore. Refer to Fig. Dl-33.

f.
Install
bearing cap, with lower bearing half, on connecting rod. Torque bolt nuts to 30 to 40 lb-ft. [4,1 a 5,5 kg-m.].
g.
Install
all other piston and connecting rod as­
semblies in same manner.

h.
Check
end clearance
between
connecting rods
on each crankpin with a feeler
gauge.
Clearance should be .005,/ to .012" [0,127 a
0,305
mm.].

Dl-76.
Install
Oil
Pump
Intake
Pipe
and
Screen Assembly

Check
mating surfaces of oil pump intake pipe

and
engine
cylinder block to be certain that they

are
clean. Secure the pipe and screen assembly,
with a new gasket, to
engine
cylinder block with two attaching screws. See Fig. Dl-34. Torque screws 6 to 9 lb-ft. [0,83 a 1,24 kg-m.].

Dl-77.
Install
Oil Pan

Refer
to Fig. Dl-35.

Be
certain the flange surface of oil pan and cor­
responding surface of
engine
cylinder block are
clean.
Install
a new oil pan gasket on the cylinder
block.
Secure
oil pan to cylinder block with mount­ ing bolts. Torque
bolts
10 to 15 lb-ft [1,4 a 2,1

kg-m.].

Dl-78.
Install
Flywheel

Refer
to Fig. Dl-7.

a.
Check
flywheel flange of
engine
crankshaft and corresponding surface of flywheel to
be
certain that
FIG.
Dl-33—INSTALLING
PISTON
AND

CONNECTING
ROD
ASSEMBLY
1—Ring
Compressor

FIG.
Dl-34-^-OIL
PUMP
INTAKE PIPE
AND

SCREEN
INSTALLATION
1—Pipe and Screen
97

'Jeep'
UNIVERSAL SERIES SERVICE
MANUAL

Dl
both are clean. Any foreign material on either of

these
surfaces
will
cause flywheel run out and en­
gine
vibration. Position flywheel to crankshaft and
secure with six mounting bolts. Torque mounting
bolts
50 to 65 lb-ft. [6,91 a 8,98 kg-m.].

Note:
Flywheel mounting
bolts
are unevenly
spaced so that flywheel can be installed in only
one position.
This
assures correct balance of fly­
wheel and crankshaft.

b.
Mount a
dial
indicator on flywheel housing
flange of cylinder block and index its plunger to
the flywheel surface. Measure flywheel run out.

Maximum
allowable run out is .015"
[0,381
mm.].
Dl-82.
Install
Cylinder
Head Assembly

Refer
to Fig. Dl-9.

a.
Wipe cylinder head face of
engine
cylinder
block, and be certain no foreign material has fallen
into the cylinder bores, bolt holes, or in the valve

lifter
area.
It is
good
practice to clean out bolt

holes
with compressed air.

b.
Install
a new cylinder head gasket on the
cylin­

der
block. Dowels in the block
will
hold the gasket

in
position. Always handle gaskets carefully to

avoid
kinking or damage to the surface treatment
of the gasket. Apply Perfect Seal Aerosol
Spray
Sealer
Part
No.
994757
on cylinder head gaskets.

Dl-79.
Install
Clutch
and Flywheel Housing

a.
Note
marks made on clutch assembly and fly­
wheel during
engine
disassembly. Position clutch
assembly to flywheel, according to
marks,
and
fasten
loosely
with six attaching bolts. Torque

bolts
in rotation, one
turn
at a time, to 30 to 40 lb-ft. [4,1 a 5,5 kg-m.].

b.
Engage fork of clutch linkage to clutch and
position flywheel housing to
engine
cylinder block.
Secure
housing to block with six mounting bolts.

Torque
bolts
30 to 40 lb-ft. [4,1 a 5,5 kg-m.].

D1-80.
Install
Camshaft

Insert
camshaft into camshaft bearings of
engine

cylinder
block carefully to avoid damage to bear­
ing surfaces. Make certain camshaft journals are

properly
seated in bearings.
12695

FIG.
D1-36—CAMSHAFT
AND
VALVE LINKAGE
1—
Rocker
Arm

2—
Push
Rod 3—
Valve
Lifter

4—
Camshaft
14203

FIG.
Dl-37—CYLINDER
HEAD
BOLT TIGHTENING SEQUENCE c.
Clean
gasket surface of cylinder head and care­

fully
place on the
engine
block dowel pins.

d.
Clean
and lubricate the cylinder head
bolts
with

a
sealing compound
(Part
No. 994757, or equiv­

alent).

e.
Install,
and alternately tighten the head bolts,
a
little at a time, in the sequence shown in Fig.

Dl-37.
Torque
bolts
65 to 85 lb-ft. [9,0 a 11,8

kg-m.].

f.
Tilt
the rocker arms toward the push rods and locate the top of each push rod in its rocker arm
seat.

g.
Mount the rocker arm and shaft assembly, tightening the bracket
bolts
a little at a time.
Torque
the bracket
bolts
25 to 35 lb-ft. [3,5 a 4,8

kg-m.].
Do not overtighten.

h.
See Section Fl and F2 for
engines
equipped

with
exhaust emission control.

D1-81.
Install
Valve Lifter
and Push Rod

Make
certain valve lifter guide
holes
and adjacent
area
of cylinder block are clean.
Liberally
lubricate
the camshaft and valve lifter bores with
engine

oil,
and install valve lifters.
Each
valve lifter must slide freely in its guide hole. See Fig. Dl-36.
Dl-83.
Install
Rocker Arm Cover

Install
a new gasket on each rocker arm cover.
Secure
each rocker arm cover to corresponding

cylinder
head with four attaching screws.
Install

the positive crankcase ventilation valve on right

rocker
arm cover. 99

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

E

FIG.
E-9—LOW-SPEED
SYSTEM

1—
Body
Flange 6—Idle Air Bleed

2—
-Idle
Adjustment Screw Port
7—Air
By-pass
3—
Idle
Port 8—Economizer

4—
Idle
Well
9—Metering Rod Jet
5—
Low
Speed Jet 10—Idle Adjustment Screw
in
Pars.
"A"
through
"D";
however, because of the

Idle
Limiter
Cap,
the idle mixture screw
CANNOT

be adjusted in the counter-clockwise
(rich)
direc­
tion. The adjustment is made from the
rich
stop

position and the mixture screw is turned in (clock­
wise) approximately %
turn
to
"Lean
Best
Idle."
Refer
to Fig. E-6.

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 or vacuum
gauge
to
engine.

c.
Warm
up
engine
and stabilize temperatures.

d.
Adjust
engine
idle to
speed
desired, using throt­tle 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
-rich)
until
maximum
speed
is just regained at a "lean as
possible" mixture adjustment.

E-15.
High-Speed System

Fuel
for part-throttle and full-throttle operation
is supplied through the high-speed system shown

in
Fig. E-10. A metering rod and metering rod

jet
control the amount of fuel admitted through the nozzle for high-speed operation. The lower
end of the metering rod is calibrated in size to

accurately
meter the fuel required. As the rod
|
13346

FIG.
E-10—HIGH-SPEED
SYSTEM

1—Nozzle 7—Pump Diaphragm
Spring

2
—Metering
Rod 8—Diaphragm Assembly

3—
Pump
Lifter
Link
9—Chamber

4—
Metering
Rod Arm Assembly
10—Metering
Rod Jet 5—
Diaphragm
Shaft
11—Carburetor
Casting

6—
Upper
Pump Spring 12—Carburetor Bore is automatically raised and lowered in the jet,
the opening in the jet is varied in size to supply
fuel
proportionate to the requirements through the
higher
speed
and power range. The metering rod
is both mechanically and vacuum controlled and is
attached to the metering rod arm assembly.
During
part-throttle operation, vacuum in chamber

pulls
diaphragm down, holding metering arm
assembly against pump lifter
link.
Movement of the metering rod is controlled by the
pump lifter
link
which is attached to the carburetor
throttle shaft. At all
times
vacuum in the chamber
is strong
enough
to overcome the tension of pump

diaphragm
spring. Upper pump spring serves as

a
bumper upon deceleration and as a delayed
action spring upon acceleration. Under any operat­ ing condition, when the pump diaphragm spring
overcomes vacuum in the chamber, the metering

rod
will
move
toward the wide throttle (power) position.

Note:
Nozzle is pressed in and should not be
removed.

E-16.
Metering Rod Adjustment

Check
metering rod adjustment each time the

carburetor
is reassembled. Before adjustment is
made, be sure that the flat of metering rod arm
is parallel to the flat of pump lifter
link
as shown
(Fig.
E-10.).
With
the throttle valve
seated
in
car­

buretor
bore, press down on the upper end of
diaphragm
shaft until the diaphragm
bottoms

in
the vacuum chamber. The metering rod should
now
seat
on casting with the metering rod
arm
flat against the pump lifter
link.
If the meter­
ing rod
does
not
seat
on the casting (check by 115

'Jeep9
UNIVERSAL
SERIES
SERVICE
MANUAL

E
exterior moving parts of a carburetor are
often

responsible for unsatisfactory performance.
For
this

reason,
efficient carburetion depends upon careful cleaning and inspection while servicing.

a.
Thoroughly clean carburetor castings and metal
parts
in carburetor cleaning solvent.

Caution:
Accelerator pump plunger and any fiber

or
rubber parts should never be immersed in
car­

buretor
cleaner. Wash pump plunger in cleaning
solvent.

b.
Blow out all passages in the castings with com­
pressed air. Dry all parts with compressed air.

Make
sure all jets and passages are clean. Do
not use wire to clean fuel passages or air bleeds.

c.
Check
inlet valve
needle
and seat for wear. If

wear
is noted, the assembly must be replaced.

d.
Check
float hinge pin for wear and check float
for damage.

e.
Check
throttle and choke shaft bores for wear

and
out-of-round.
f. Inspect idle mixture adjustment
needles
for
burrs
or
grooves; replace if damaged.
g. Inspect cup of accelerator pump plunger; re­
place if damaged, worn, or hardened. Inspect pump

well
in bowl for wear or scoring.

h.
Check
filter screens for
dirt
or lint.
Clean,
and

if
they remain
clogged,
replace.

i.
If for any reason parts have
become
loose
or
damaged in the cluster assembly, the assembly
must be replaced.

Note:
Use ijew gaskets whenever the carburetor
is disassembled.

E-37.
Throttle Body Assembly
a.
Install
idle mixture adjustment
needles
and
springs in throttle body. Tighten finger-tight, then
unthread
one
turn
as a preliminary adjustment
setting.

Caution:
Do not force idle mixture adjustment
needles
against
seats
or damage may result.

b.
Invert
fuel bowl body and place new throttle
body gasket on bowl. Fasten throttle body to bowl
body with three screws and lockwashers; tighten

securely.

E-38.
Fuel
Bowl Body Assembly

a.
Drop steel discharge check
tall
of accelerator
pump into discharge hole.
Install
pump discharge

spring
and T-shaped retainer. Stake retainer in
place.

Note:
Top of retainer must be flush with flat

surface
of fuel bowl body.

b.
Install
two inserts in main well. Align surface
on lip of insert with flat surface in recess on top
of main well.
Install
venturi cluster with gasket,

and
tighten mounting screws evenly and securely.

Be
certain that center screw is fitted with fiber gasket, and that a special smooth shank screw is
used.
c.
Install
two main metering jets, power valve
gasket and power valve.

d.
Install
small aluminum inlet check
ball
in ac­

celerator
pump inlet at
bottom
of pump well. In­

sert
pump return spring into well, and center by
pressing spring downward with finger.

e.
Install
pump inlet screen in
bottom
of fuel

bowl.

E-39.
Air
Horn Body
Assembly

a.
Install
choke lever and collar on choke shaft.

Prong
on choke lever must face away from air

horn
body and be on top of choke trip lever.
b.
Install
choke shaft and lever assembly into the

air
horn. Choke rod
hole
in the choke lever must
face fuel inlet side of carburetor.

c.
Install
choke valve plate in choke shaft so that
letters RP
will
face upward in finished carburetor.
Install
two new valve plate attaching screws, but
do not tighten securely until valve plate is centered.

To
center choke valve plate on choke shaft, hold
choke valve tightly closed, then slide choke shaft

inward
to obtain approximately .020" [0,508 mm.]

clearance
between
choke trip lever and choke lever

and
collar assembly. Tighten choke valve screws

securely,
and stake lightly in place. Choke valve

will
be perfectly free in all positions when installed
correctly.

d.
Insert
outer accelerator pump lever and shaft as­ sembly into air horn body, with lever pointing to­

ward
choke shaft.
Install
inner pump arm, with plunger
hole
inward,
and tighten set screw securely.
Position pump plunger assembly on inner pump
arm,
with pump shaft pointing
inward,
and install

retainer.

e.
Install
needle
seat screen on inlet valve seat. In­

stall
seat and gasket in air horn body. Tighten seat
securely with a wide-blade screwdriver.
f.
Install
power piston into vacuum cavity.
Lightly
stake piston retainer washer in place. Piston should

travel
freely in cavity.
g.
Install
air horn gasket on air horn body, fitting
gasket over guide pin.

h.
Attach inlet valve
needle
to float.
Carefully

position float and insert float hinge pin. Drop tang
at
rear
of float arm downward toward air horn.

i.
Install
fuel inlet fitting, if removed.

j.
With
air horn assembly inverted, measure the distance from the air horn gasket to top of float
at toe \%£f [27,78 mm.] for standard carburetors

and
\%i [29,36 mm.] for exhaust emission control
equipped carburetors, as shown in Fig. E-23. Use
float level
gauge
J-5127-2. Bend float arm as re­

quired
to adjust float level.

k.
With
air horn body held upright, measure dis­
tance from gasket to
bottom
of float
pontoon
at outer end. Use a l7/s" [47,625 mm.] float drop

gauge.
Bend float tang, as required, to adjust float

drop.
See Fig. E-24.

I.
Carefully
place air horn body on fuel bowl
body, making certain that the accelerator pump
plunger is properly positioned in the pump well.
Lower
the cover gently, straight down; install air 123