service JEEP CJ 1953 Manual Online

'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

'Jeep'
UNIVERSAL
SERIES
SERVICE
MANUAL

E
is generally caused by excessive
engine
idle speed

in
combination with retarded ignition timing,

engine
heat soak or the use cf low octane fuel.
Should
engine
dieseling
(engine
running after ignition key is turned off) be experienced on V-6

engine
equipped vehicles, installation of Idle Stop
Valve
Kit
Part
No.
991722
will
correct the
difficulty.

E-43.
Fast
Idle Adjustment
No fast idle speed adjustment is required.
Fast

idle is controlled by the curb idle speed adjustment

screw.
If curb idle speed is correctly set and the choke rod is properly adjusted, fast idle speed
will

be correct;

E-44.
Dash Pot Adjustment —
F4
and V-6 Engine

•
Refer to
Figs.
E-27 and E-28. Before adjusting the dash pot, the
engine
idle speed

and
mixture should be correctly adjusted.
With
the

engine
idling at normal operating temperature,
adjust
the dash pot as follows:

The
dash pot adjustment is made with the throttle
set at curb idle (not fast idle). Loosen dash pot lock
nut and
turn
the dash pot assembly until dash pot
plunger contacts the throttle lever without the plunger being depressed.
Then
turn
the dash pot
assembly 2turns against the throttle lever, de­ pressing the dash pot plunger. Tighten the lock nut
securely. As a final check, open carburetor and
allow throttle to snap closed. Time dash pot delay­ ing action from the point where the throttle lever
hits the dash pot to the point where the lever
stops

moving. The dash pot should delay or cushion
closing action for two seconds by saying, "One
thousand and one, one thousand and two."
14204

FIG.
E-27—DASH
POT
ADJUSTMENT—V6
ENGINE
1—
Throttle
Lever
3—Dash Pot
2—
Plunger
4—Lock
Nut
E-45.
FUEL
PUMP
(DOUBLE-ACTION)
—

HURRICANE
F4
ENGINE

•
Early
Models

The
double-action fuel pump consists of a metal
body, a rubber diaphragm, rocker arm, valves,
FIG.
E-28—DASH
POT
ADJUSTMENT—F4
ENGINE

1—
Throttle
Lever
3—Dash Pot
2—
Plunger
4—Lock
Nut springs, gaskets, and a glass sediment bowl complete

with
strainer.
The
metal pump body provides
a
work­
ing housing for the diaphragm, lever, valves, and springs. The fuel pump is mounted on the left side
of the
engine
and is actuated by an eccentric on the
camshaft. An air
dome
is cast into the metal cover
to relieve the carburetor
needle
valve and the fuel
pump diaphragm of excessive pressure when the

carburetor
needle
valve is closed.

Tracing
pump operation from the beginning, the
camshaft eccentric forces the diaphragm up, over­
coming spring pressure.
This
action creates a
partial
vacuum
in the pump chamber.
Fuel
from the main

tank
is forced into the low-pressure pump chamber
through the open disc valve. Incoming fuel supplies
the force necessary to open the valve, which is

a
one-way check valve. As the
engine
camshaft continues to rotate, spring pressure forces the

diaphragm
downward as the pump rocker arm
follows the camshaft eccentric to its low
spot.

The
downward action of the diaphragm
closes

the intake valve and forces fuel to the carburetor

reservoir
through the pump
outlet
valve. Both intake and
outlet
valves are one-way check valves
opened and closed by fuel flow. No mechanical components are required in the control of valve
operation.

Fuel
is delivered to the carburetor only when the float
needle
is off its seat. When the fuel level in the carburetor bowl is high enough for the float to
force the
needle
against its seat, pressure backs up
to the fuel pump air
dome
and causes the diaphragm
to
stop
pumping. In this position, the pump is said
to be balanced because the pressure in the pump- to-carburetor line equals that of the diaphragm

spring.
In this way, fuel from the pump to the
carburetor
is always under pressure. The carburetor

uses
fuel, causing the float to drop and
pull
the

carburetor
needle
valve off its seat. Pressure in the pump immediately drops as fuel is delivered to the

carburetor
reservoir. Almost instantaneously the

diaphragm
again starts operating to pump more 125

'Jeep'
UNIVERSAL
SERIES
SERVICE
MANUAL

E
E-47.
Reassembly

•
Refer to Fig. E-29.
Install
the valve gaskets, valves, valve retainer and
secure them with the valve retainer screws. Make
sure that the inlet and
outlet
valves are in their proper positions. Place the diaphragm spring re­
tainer in position on the diaphragm
pull
rod
and
install diaphragm spring. Position the
dia­

phragm assembly in pump
body
and attach the
cover to pump body, with file marks aligned, with
the six attaching screws. Do not draw the screws
up tight.
Install
rocker arm spring, rocker arm

pin
washers, rocker arm and rocker arm pin.
With

rocker
arm positioned on the diaphragm rod, draw
the six pump
body
screws up evenly and securely.
Install
the filter screen, cork gasket and sediment
bowl and secure them firmly with the thumb screw
on the bowl clamp.

E-48.
Vacuum
Pump

The
double-action fuel pump resembles two single-
action pumps placed one
above
the other. A single
fuel pump rocker arm actuates the two separate diaphragms. One diaphragm is part of the fuel
delivery pump and operates as described in Par.
E-45.
The other diaphragm is part of the vacuum
pump and operates as described here.

As
the actuating lever forces the diaphragm upward against spring pressure, air is forced through the

outlet
port
into
the
engine's
intake manifold. On
the return stroke, spring pressure forces the
dia­
phragm downward, creating a
partial
vacuum and
opening the inlet valve. In this manner, air is pumped out of the windshield wiper motor and
into

the intake manifold. When the wiper motor is shut off, manifold vacuum holds the diaphragm against its spring so that the
full
motion of the actuating
lever is not accompanied by a
complete
up-and-
down motion of the diaphragm.

When
the windshield wiper motor is turned on, but manifold vacuum is greater than the vacuum
created by the
booster
pump, air
flows
from the
wiper motor through both valves of the vacuum
booster.
As manifold vacuum drops off as a result
of the
engine
operating under low
speed
and high load, the vacuum created by the vacuum
booster

will
be greater than
engine
intake manifold vacuum

and
the pump
will
operate the wiper motor when the wiper control switch is turned on.

•
Refer to Fig. E-29. Remove the
eight
cover attaching screws and
lockwashers, and remove the cover, diaphragm

spring
and spring seat. Detach the diaphragm rod
from the rocker arm and remove the diaphragm.
The
valve assemblies are pressed
into
the cover

and
body
and lightly staked. They may be removed
with the point of a knife blade. If installing new valves be sure the inlet and
outlet
valves are
correctly positioned and stake them lightly with

a
small punch.
Assemble the vacuum pump in the reverse order
of disassembly, drawing the cover attaching screws up evenly and tightly.
E-49.
Fuel
Pump
Testing

Four
tests
are presented in following paragraphs to
test
for proper operation of the fuel pump. In addi­
tion, check the following:

a.
Check
for secure mounting of the fuel pump.

The
rocker arm may be working the entire pump
up and down, rather than just the pump
dia­

phragms.
b. Remove and clean the fuel sediment bowl.
c.
Check
all fuel lines.
E-50.
Volume
Check

To
measure fuel pump capacity (amount of fuel
delivered in a given time) disconnect the pump-to-

carburetor
line at the carburetor end. Place the

open
end of the line in a suitable container.
Start

the
engine
and operate at normal idle speed.
Delivery
should be one quart U.S. [1 ltr.] within
one minute.

E-51.
Pressure
Check

To
measure fuel pump pressure (force of fuel de­

livery)
disconnect the pump-to-carburetor line
at the carburetor end. Plug a pressure
gauge
and T-fitting
into
the
open
end of this line and
into
the

carburetor.
Start
the
engine
and operate at normal
idle speed. Pressure should be 2J4 to 3% psi.
[0,716
a
0,264
kg-cm2] at 1800 rpm. and at 16"
[406 mm.]
above
the
outlet.

E-52.
Vacuum
Check

To
measure fuel pump vacuum (pull of. the pump
at the inlet side) disconnect the pump-to-fuel-tank
line at the fuel pump. Attach a vacuum
gauge
to the fuel pump inlet.
Start
the
engine,
accelerate to
specified speed, and hold this
engine
speed
while
taking a
gauge
reading. Permissible
gauge
reading
is 8* [203 mm.] of mercury [Hg] at 1200 rpm. and
10j^'
[267 mm.] at 1800 rpm.
E-53.
Vacuum
Booster
Check

To
test
the condition of the vacuum
booster
pump,
disconnect both inlet and
outlet
lines at the pump.

Attach
a vacuum
gauge
to the windshield wiper
connection at the pump.
Start
the
engine,
accelerate
to
2000
rpm., and hold this
engine
speed
while taking a
gauge
reading. Permissible
gauge
reading
is 10* to 14" [254 a 356 cm.] of mercury [Hg].
E-54.'
FUEL
PUMP
(SINGLE-ACTION)
—
HURRICANE
F4
ENGINE
•
Early
Models.
Vehicles with electric windshield wiper motors are
equipped with a single-action fuel pump (Fig.

E-30).
The fuel pump cam lever is activated by an eccentric on the
engine
camshaft. When the
car­

buretor float
needle
valve closes, accumulation of
fuel in the pump
extends
the diaphragm spring.

This
action causes the rocker arm linkage to be­
come
inoperative until the pressure on the
dia­
phragm and spring is reduced. The fuel pump dis­
charge pressure is thus controlled by the diaphragm

spring.
This
provides a steady supply of fuel to the
carburetor
at a fairly constant pressure. 127

E

FUEL
SYSTEM
E-55.
Fuel
Pump
Removal

To
remove the fuel pump from the engine, dis­
connect the inlet and
outlet
fuel lines. Remove the two fuel pump body attaching nuts, lock

washers,
and washers, and pull the fuel pump and gasket free of the engine.
FIG.
E-30
—
FUEL
PUMP—HURRICANE

F4 ENGINE,
EARLY
MODELS
1—
Housing
Cover

2— Air
Dome
Diaphragm

3—
Strainer

4—
Screw
and
Washer

5—
Housing

6—
Cover
Screw
and
Lock
Washers
7—
Main
Diaphragm

8—
Pump
Body

9— Cam
Lever
Return
Spring

10— Pin
Retainer

11— Cam
Lever

12— Cam
Lever
Pin

13—
Lever
Seal
Shaft
Plug
E-56.
Fuel
Pump
Disassembly

Note:
The fuel pump is serviced with a repair kit.

Individual
service parts are also available. The
valves are not replaceable but are serviced as part of the valve housing.

a.
Before disassembly of the fuel pump,
mark
the
three castings (see Fig. E-30) to ensure positioning

in
the same relation upon assembly. b. Remove the inlet and
outlet
fuel fittings from
the pump.
c. Remove the screws and washers and separate the housing from the pump body.

d.
Remove cover screws and lock washers and
then remove housing cover,
dome
diaphragm and

strainer.

e.
Remove cam lever return spring and lever seal
shaft plug.
f. Remove retainer pin, cam lever pin and cam
lever.
g. Remove main diaphragm.

Note:
Do not remove valves from housing as they

are
serviced with the housing.

Note:
The oil seal (at top of spring in diaphragm
assembly) seals the spring side of the fuel
dia­

phragm
from the crankcase. Any deposit, in
excess

of a few drops, of oil on the diaphragm, indicates
leakage past the oil seal. Be sure the seat for the
seal
in the pump body is clean and smooth.

E-57.
Fuel
Pump
Cleaning
and
Inspection

Caution:
Do not immerse valves or diaphragm in
-cleaning solvent; wipe clean.

Clean
all metal parts of the fuel pump in solvent.
Brush
with a stiff-bristled brush. Dry with com­
pressed air.
Check
all parts to see that they are not

cracked
or broken and that the screw threads are
not damaged.

E-58.
Fuel
Pump
Reassembly

a.
Position the new main diaphragm on pump body
and
hold it in position while installing cam lever

in
position.
b.
Install
cam lever pin, pin retainer and lever

seal
shaft plug.
c.
Install
cam lever return spring.

d.
Position strainer, air
dome
diaphragm and hous­
ing cover on housing and secure with screw and
lock
washers.

e.
Position housing on pump body and secure with screw and washers.
First
start all screws one or
two turns:
Then
tighten the screws alternately and
securely.

Note:
Before placing housing on pump body
note

position of align marks made before disassembly.
f.
Install
the fuel inlet and
outlet
fittings.

Note:
Lubricate
forked end of cam lever and cam
lever pin.

Caution:
Do not overtighten screw. 128

'Jeep9
UNIVERSAL
SERIES
SERVICE
MANUAL

E-59.
Fuel
Pump Installation

a.
Make certain mating surfaces of fuel pump and
engine
cylinder case are clean. Cement a new gasket
to mounting
flange
of fuel pump.
b. Position fuel pump on cylinder block, so that

cam
lever of pump rests on fuel pump cam of cam­
shaft. Secure pump to block with two cap screws

and
lock washers.
c. Connect intake and
outlet
fuel lines to fuel
pump.

E-60.
FUEL
PUMP
(SINGLE-ACTION)
—
HURRICANE
F4
ENGINE
•
Late
Models.

The
Hurricane F4
engine
is equipped with a single-
action fuel pump (Fig.
E-31).
The fuel pump cam lever is activated by an eccentric on the
engine

camshaft. When the carburetor float
needle
valve
closes, accumulation of fuel in the pump
extends

the diaphragm spring.
This
action causes the rocker

arm
linkage to
become
inoperative until the pres­
sure on the diaphragm and spring is reduced. The fuel pump discharge pressure is thus controlled by
the diaphragm spring.
This
provides a steady sup­ ply of fuel to the carburetor at a fairly constant
pressure.

E-61.
Fuel
Pump Removal

To
remove the fuel pump from the
engine,
dis­
connect the inlet and
outlet
fuel lines. Remove
the two fuel pump
body
attaching nuts, lock washers, and washers, and pull the fuel pump and
gasket free of the
engine.

E-62.
Fuel
Pump Disassembly

Note:
The fuel pump is serviced with a repair kit.

Individual
service parts are also available. The
valves are not replaceable but are serviced as part
of the valve housing.

•
Refer to Fig. E-32.

a.
Remove filter bail assembly, bowl,
element,

spring,
and gasket from filter cover. b.
File
a locating
mark
on the
edges
of the valve
housing and the pump body. Remove the six at-

14280
FIG.
E-32—FUEL
PUMp—

HURRICANE F4 ENGINE,
LATE
MODELS

12988

FIG.
E-31—FUEL
.PUMP-

HURRICANE F4 ENGINE,
LATE
MODELS 1—
Bail

2—
Bowl

3—
Spring

4—
Filter
5—
Gasket

6— Pump Body 7—
Gasket

8—
Valve
Assembly 9— Screws 10—
Valve
Housing
11—
Valve
Assembly
12— Screws
13—
Diaphragm
and Oil Seal 14— Pump Body
15—
Cam
Lever
Spring 16—
Cam
Lever

17—
Gasket

18—
Cam
Lever
Pin and Plug 129

E

FUEL
SYSTEM
taching screws and valve housing from the fuel
pump body.

c.
Remove the two screws in the valve housing
and
separate the filter cover and air
dome
dia­
phragm.

d.
Remove the cam lever return spring, plug,
cam
lever pin, and cam lever from the pump body.

Tap
the cam lever pin out of body, using a drift
inserted through the small
hole
in the pump body.
e. Remove diaphragm from pump body.
f. Under normal service, the pump may be cleaned without further disassembly.

Note:
The oil seal (at top of spring in diaphragm
assembly) seals the spring side of the fuel
dia­
phragm
from the crankcase. Any deposit, in
excess

of a few drops, of oil on the diaphragm indicates leakage past the oil seal. Be sure the seat for the

seal
in the pump body is clean and smooth.

E-63.
Fuel
Pump Cleaning and Inspection

Caution:
Do not immerse valves or diaphragm
in
cleaning solvent; wipe clean.

Clean
all metal parts of the fuel pump in solvent.
Brush
with a stiff-bristled
brush.
Dry with com­
pressed
air.
Check
all parts to see that they are not
cracked
or broken and that the screw threads are
not damaged.

E-64.
Fuel
Pump Reassembly
•
Refer to Fig. E-32.

a.
Assemble the valve housing and filter cover, using a new air
dome
diaphragm. The opening

in
the air
dome
diaphragm is located over the
intake
valve. The filter cover is positioned cor­
rectly
when the inlet passage in the cover aligns

with
the inlet valve. Tighten the attaching screws
alternately and securely.

b.
Lubricate
diaphragm assembly shaft, around

oil
seal, with
engine
oil. Position diaphragm as­ sembly on valve housing and thread all the attach­ ing screws through diaphragm.
(This
helps avoid
damage to the screw
holes
in diaphragm.)

c.
Place diaphragm assembly and valve housing
in
position on pump body (align marks made
before disassembly).
First
start all screws one

or
two threads; then tighten the screws alternately

and
securely.

d.
Lubricate
forked end of cam lever, pin bore
of body, and corresponding
hole
in lever, and the
pin
itself with
engine
oil.

Note:
Forked
end of lever
goes
around diaphragm
shaft. Be sure
loose
bumper washer on diaphragm shaft is on top of lever and
between
lever and fixed
washer
on shaft.
e.
Install
lever and pin. To install pin, use a drift
and
tap pin into the
hole
in the body until it hits
the
stop
on the
bottom
of the hole;
move
the lever while tapping, to align
hole
in lever with the pin;
then install plug.
Install
lever return spring.
f.
Install
a new filter bowl gasket in filter cover.
Place
bail
assembly in ears on cover and swing
to one side.
Install
spring and new filter element in
bowl and install bowl on pump. Position
bail
as­
sembly under bowl; tighten retainer screw.

Caution:
Do not overtighten screw.

E-65.
Fuel
Pump Installation

a.
Make certain mating surfaces of fuel pump and

engine
cylinder case are clean. Cement a new gasket to mounting flange of fuel pump.

b.
Position fuel pump on cylinder block, so that

cam
lever of pump rests on fuel pump cam of cam­
shaft. Secure pump to block with two cap screws
and
lock washers. Torque
bolts
13 to 17 lb-ft. [1,8
a
2,3 kg-m.].

c.
Connect intake and
outlet
fuel lines to fuel
pump.

E-66.
Fuel
Pump Testing

Whenever
the fuel pump is to be checked for pres­

sure
or volume, follow the procedure outline in

Par.
C-23 of this manual.
Fuel
pump pressure is
important
for low pressure
will
seriously affect en­

gine
operation and high pressure can cause exces­
sive fuel consumption and flooding of the carbure­
tor.
Should there be any doubt of normal opera­
tion, check the procedure as outlined in Par. C-23.
In
addition to proper fuel pressure, volume of the
pump is also important. When testing for proper
pump pressure, be certain to also
test
for volume
as the pump may build up sufficient pressure, but
fail
to produce sufficient volume.

E-67. FUEL
PUMP
—
DAUNTLESS
V-6
ENGINE

Jeep vehicles equipped with the Dauntless V6-225

engine
have a special fuel pump which has a metering
outlet
for a vapor return system. Any

vapor
which forms is returned to the fuel tank
along with hot fuel through a separate line along­
side the fuel supply line.
This
greatly reduces any
FIG.
E-33—FUEL PUMP—DAUNTLESS V-6 ENGINE
1
—Fuel
Outlet 2—Vapor
Return
3—Fuel
Inlet

130

'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

E
portant that
these
lines are not accidentally re­
versed.

When
installing the fuel tank on late model vehicles, position the tank
between
the frame
rail

to allow space to connect the fuel line(s), vent
hose

and
sending unit wire. After connecting
these
items, align and secure tank to frame brackets.
Position filler
hose
on tank filler neck and tighten
hose
clamp.
Fill
tank with fuel and check for leaks.

When
installing the fuel tank on early model vehicles, reverse the order of removal as given in

Par.
E-73.

E-75.
Fuel
Tank
Cap

A
surge pressure type fuel tank filler cap is used on

all
models.
This
is necessary to prevent fuel leakage
from
the cap vent opening when the vehicle is on a
side slope. Two spring loaded relief valves which
open when venting is required are built into the
cap.
Should the pressure valve
fail
to open, pressure
in
the tank may force fuel by the carburetor inlet
valve causing flooding.
Failure
of the vacuum valve may prevent flow of fuel to the carburetor. Should
the valves
fail
to vent install a new cap.

Note:
Vehicles having a
Fuel
Evaporative
Emis­

sion System are equipped with a non-vent sealed gas cap. The sealed cap is designed to allow no
vapors to discharge to the atmosphere. No other type of cap is to be used on vehicles having this
type system.

E-76.
Fuel
Gauge Float Unit

The
fuel tank
gauge
float unit is mounted in the top
of the fuel tank and consists of a housing enclosing
a
rheostat that is actuated by the float arm, and a
float
which
moves
with the fuel level in the tank.
On
V-6 and current production F4
engine
equipped vehicles, the fuel
outlet
pipe is integral with the
float
unit.
The fuel
outlet
pipe has a mesh filter on the inner end.

Note:
Under no circumstances should a fuel tank

gauge
be installed without a mesh filter element.

The
filter,
outlet
pipe, and float unit are locked as

an
assembly to the top of the fuel tank. To remove,

turn
the lock plate that secures the float unit
assembly.

E-77.
Fuel
Lines

Check
lines and connections occasionally for leaks,
and
for severe kinks that might restrict the flow of
fuel. If an excessive amount of
dirt
is found in the
carburetor
or fuel pump, the fuel tank should be
drained
and the fuel lines blown out with com­
pressed air.

All
rubber fuel lines and their respective clamps should be checked occasionally to be certain they
are
correctly positioned and not leaking. 133

E

FUEL
SYSTEM
E-78. SERVICE DIHGNOSIS
Symptoms Probable Remedy

Excessive
Fuel
Consumption:
Tires
improperly inflated Inflate

Brakes
drag Adjust
Engine
operates too cold Check thermostat
Heat control valve inoperative Check thermostatic spring
Leak
in fuel line Check all connections

Carburetor
float level high. See
"Carburetor"
section
Accelerator pump not properly adjusted Adjust

Leaky
fuel pump diaphragm Replace
Loose
engine
mountings causing high carburetor fuel level Tighten Ignition timing slow or spark advance stuck See "Distributor" section

Low
compression. Check valve tappet clearance
Air
cleaner dirty
.
Remove and clean

Engine
Hesitates on Acceleration: Accelerator pump
does
not function perfectly.
...................
.Replace piston and rod or adjust
Carburetor
float level. ... .Adjust

Spark
plugs Replace or clean and adjust

Low
compression Check valves

Distributor
points—dirty or pitted Replace

Weak
condenser or coil Replace

Carburetor
jets restricted Remove and clean

Excessive
engine
heat See "Engine" section

Engine
Stalls—Won't Idle:
Improper
condition of carburetor See
"Carburetor"
section

Low
speed
jet restricted Remove and clean
Dirty
fuel sediment bowl screen Remove and clean

Air
cleaner dirty Remove and clean

Leaky
manifold or gasket Replace

Fuel
pump diaphragm porous. Replace
Loose carburetor. Tighten
flange
nuts

Water
in fuel
Drain
and clean system

Improper
ignition. .See "Distributor" section

Spark
plugs Clean and adjust

Valves
sticking.
Grind
valves 134

'Jeep'
UNIVERSAL SERIES
SERVICE
MANUAL

E
E-79.
FUEL
SYSTEM SPECIFICHTIONS
CARBURETOR SPECIFICATIONS HURRICANE
F4 (See
Note)

Make
Model.
Throttle Bore

Main
Venturi.
Low
Speed
Jet

Main
Metering Jet Idle Port

Nozzle
Bleed In Body
Pump Jet
Float
Setting

Engine Idle RPM Dash Pot
Setting
. ......

CARBURETOR SPECIFICATIONS HURRICANE
F4 (See
Note).

Make Model
Throttle Bore
Main
Venturi
Low
Speed
Jet
Main
Metering Jet Idle Port

Nozzle
Bleed In Body
Pump Jet.
Float
Setting
Engine Idle RPM Dash Pot
Setting
Without Exhaust Emission Control

Carter

YF-938SD

lY2n
[3,81 cm.]

1M"
[3,18 cm.]
.028"
[0,711
mm.]

.0935"
dia.
[2,375
mm.]
.184" x .030" [4,70 a
0,765
mm.]
.0225
"[0,571
mm.] .031"
[0,787
mm.] Vk" [7,39 mm.] 600 Without Exhaust Emission Control

Carter

YF-4002-S

\y%"
[3,81 cm.]

1M"
[3,18 cm.]
.031"
[0,794
mm.]
.091" dia.
[2,311
mm.]
.184" x .030" [4,70 a
0.765
mm.] .028"
[0,713
mm.]
.025"
[0,635
mm.]
lW
[6,74 mm.] 650 — 700

With
Exhaust Emission Control
Carter

YF-4366-S,
YF-4941-S, YF-6115-S IV2" [3,81 cm.]

1M*
[3,18 cm.]
.035"
[0,889
mm.]
.089" dia.
[2,261
mm.]
.184" x .030" [4,70 a
0.765
mm.] .028"
[0,713
mm.]
.024"
[0,609
mm.]
1W
[6,74 mm.] 700 - 750
Y%" ]3,75 mm.]

CARBURETOR SPECIFICATIONS
DAUNTLESS
V-6 (See
Note)
Make
Model
Designation
Code Number
Choke
Number of Barrels
Throttle Bore

Main
Metering Jet: Production . . High Altitude —
over
5000
ft
—
over
10,000
ft... .
Float Level Adjustment*
Float Drop Adjustment Pump Rod Adjustment**
Engine Idle RPM
Initial
Idle
Speed
Setting
Initial
Idle Mixture
Setting.

Dash Pot
Setting
Without Exhaust Emission Control
Rochester
2G

7026082
Manual
2
Wy? [3,65 cm.]
.051" - 60° [1,29 mm.]
.049" - 60° [1,24 mm.] .047" - 60° [1,29 mm.]
Hit"
[27,78
mm.] V/%" [4,76 cm.]

IH2"
J2.94 cm.] 650
-—
700 3 turns in
2 turns out
W [3,75 mm.]
With
Exhaust Emission Control
Rochester

2G

7027082-7041185
Manual

2
[3,65 cm.]
.051" - 60° [1,29 mm.]
.049" - 60° [1,24 mm.] .047" - 60° (1,29 mm.] l%2"
[29,36
mm.] V/£" [4,76 cm.]

\W
]2,94 cm.[ 650 — 700 3 turns in
2 turns out
[3,75 mm.]

*From
air horn
gasket
to top of
float
at toe.

**From
air cleaner ring to top of
pump
rod.
NOTE:
Carburetor
specifications
for
engines
equipped
with
exhaust
emission
control are
also
shown
in
section
Fl for the F4-134 Hurricane
engine,
and in
section
F2 for the V6-225 Dauntless
engine.
135