Hudson 1957 User manual

FOREWORD
The following product information will provide Hudson Service Information for the "Hornet"
V-8 Series when used in conjunction with the 1955 and 1956 Technical Service Manuals and
the 1956 "Hornet" Special V-8 Supplement.
This product information should be kept in a convenient location together with the Service
Manuals so that complete information will be available for prompt model and series reference.
AMERICAN MOTORS CORPORATION
AUTOMOTIVE TECHNICAL SERVICE
3280 South Clement Avenue
Milwaukee 7, Wisconsin
NAP56-5501 LITHOGRAPHED IN U.S.A.
1

2

3
ENGINE
(V-8)
For service procedures and general description of the
V-8 engine, refer to the 1956 Special V-8 Technical .
Service Manual Supplement.
The engines are similar in design varying only
dimensionally effecting increase in horsepower
ENGINE SPECIFICATIONS
Type
Bore
Stroke
Displacement
Compression Ratio
Carburetor
Brake Horsepower
Torque
Taxable Horsepower
Fuel
90° V-8 O.H.V.
4"
314"
327 Cu. In-
9.00:1
WCFB-Four Barrel
255 @ 4700 R.P-M.
345 Lbs. Ft. @ 2600 R-P.M.
51.2
Premium (95.9 Octane Research)
VALVES
Intake Valve Lift
Intake Valve Stem
Standard Diameter
Intake Valve Face Angle
Intake Valve Seat Angle
Intake Valve Seat Width
Intake Valve Spring Tension
Valve Closed
Valve Open
Intake Valve Stem to
Guide Clearance
Valve Guide I.D.
Exhaust Valve Lift
Exhaust Valve Stem
Standard Diameter
Exhaust Valve Face Angle
Exhaust Valve Seat Angle
Exhaust Valve Seat Width
Exhaust Valve Spring Tension
Valve Closed
Valve Open
.375"
.3412"-.3417"
29°
30°
.078"-.093"
85-91 Lbs. @ 1-13/16"
150-160 Lbs. @ 1-7/16"
-0013"-.0028"
.3430"--3440"
.375"
.3407"--3412"
44°
45°
.093"--104"
85-91 Lbs- ((4 1-13/16"
150-160 Lbs. (a) 1-7/16"

4ENGINE (V-8)
Exhaust Valve Stem to
Guide Clearance
Exhaust Guide I.D.
Valve Timing
Intake
Opens
Closes
.0018"-.0033"
.3430”-.3440"
12° 30' B.T.D.C. 244°
51° 30' A.B.D.C. Duration
PISTONS AND RINGS
Piston to Bore Clearance
Top Land
Skirt Top
Skirt Bottom
Piston Ring Gap Clearance
Top
Center
Bottom (Steel Rail I
Piston Ring Side Clearance
Top
Center
Bottom
Piston Pin to Connecting Rod
Piston Pin to Piston
.028"-.032"
.0009"-.0025"
.0009"-.0015"
.010"-.020"
.010"-.020"
.015"-.055"
.002"-.006"
.002"-.006"
.0001"-.0079"
Press Fit
Palm Press Fit in Piston at Room
Temperature
CRANKSHAFT AND BEARINGS
Main Bearing Diameter
Main Bearing Clearance
Main Bearing Cap Torque
(Except Rear)
Main Bearing Cap Torque
(Rear Only)
Crankshaft End Play
Crankshaft End Thrust
Connecting Rod Bearing Diameter
Connecting Rod Bearing Clearance
Connecting Rod Cap Torque
Connecting Rod Side Clearance
2.4983"-2.4990"
.0006"-.0032"
80-85 Ft. Lbs.
50-55 Ft. Lbs.
.003"-.007"
Front Main Bearing
2.2483"-2.2490"
.0007"-.0028"
46-50 Ft. Lbs.(oiled)
.004"-.012"
CAMSHAFT
Camshaft End Play
Camshaft Bearing Clearance
.003"-.006"
.001"-.003"

ENGINE (V-8) 5
OIL SYSTEM
Oil Pump Type
Normal Oil Pressure
Oil Pressure Release
Engine Oil Refill Capacity
Gear
10 Lbs. Min. Vii; 600 R.P.M.
55-60 Lbs.
5 Qts.
TUNE-UP DATA
Compression Pressure
Cranking Speed
(Throttle Wide Open)
Engine Idle R.P.M.
Standard and Overdrive
Hydra-Matic—In Neutral
With Air Conditioning
NOTE: When equipped with air condi-
tioning, adjust idle with air con-
ditioning unit "ON".
Ignition Timing
(Vibration Damped 1
Distributor Point Gap
Dwell or Cam Angle
Breaker Point Tension
Rotor Rotation
Spark Plugs
Auto-Lite
Champion
Gap
Torque
Cylinder Head Torque
Firing Order
140 P.S.I. Min. 0) 315 R.P.M.
550
425
475
5° B.T.D.C.
(10° B.T.D.C. optional with
Automatic Transmission or
where local fuel octane per-
mits)
.016"
28º-32º
19-23 Ozs.
Left Hand
AL-7
H-10
.035"
30 Ft. Lbs.
60-65 Ft. Lbs.
1, 8, 4, 3, 6, 5, 7, 2

6ELECTRICAL
DISTRIBUTOR (DELCO-REMY)
Model 1110887
(External Adjustment Type)
The external adjustment type distributor illustrated in Figure
1 is a 12 volt, 8 cylinder unit. The cap has a window for
adjusting dwell angle while the cap is in amounted position.
The circuit breaker plate is located below the centrifugal
advance mechanism and uses the outer diameter of the main
shaft bushing for its bearing surface. The movable plate is
held into position by a retainer clip in the upper shaft bushing.
The molded rotor serves as a cover for the centrifugal advance
mechanism. The vacuum control unit is mounted under the
movable breaker plate to the distributor housing. The contact
set is attached to the movable breaker plate. The service
replacement contact set has the BREAKER LEVER SPRING
TENSION AND POINT ALIGNMENT prefactory adjusted
and is serviced as one complete assembly. Only the point
opening ( dwell angle I requires adjusting after replacement.
FIGURE 1—Distributor Assembly
Under part throttle operation, the intake manifold vacuum is
sufficient to actuate the vacuum control diaphragm and cause
the movable plate to move, thus advancing the spark and
increasing fuel economy. During acceleration or when the
engine is pulling heavy, the vacuum is not sufficient to actu-
ate the diaphragm and the movable plate is held in the re-
tarded position by a calibrated return spring which bears
against the vacuum diaphragm.
The centrifugal advance mechanism consists of an auto-
matic cam actuated by two centrifugal weights controlled by
springs. As the speed of the distributor shaft increases with
engine speed, the weights are thrown outward against the pull
of the springs. This advances the cam causing the contact
points to open earlier and thus advancing the spark.
Lubrication
The hinge cap oiler should be filled with SAE 20 oil at each
vehicle lubrication period. When replacing the contact set
assembly, add a trace of Ball Bearing Lubricant to the breaker
cam. No other lubrication is required. The movable breaker
plate is lubricated by oil from the upper shaft bushing. In
addition to lubrication, the distributor requires periodic in-
spection of the cap and rotor, wiring, breaker points, and
timing.
Adjustment of Dwell Angle on the Car
With the engine running at idle, the dwell is adjusted by first
raising the window provided in the cap and inserting a "Hex"
type wrench into the head of the adjusting screw as shown in
Figure 2.
Figure 2—Adjusting Point Spacing (Dwell)

ELECTRICAL 7
Preferred Method:
Turn the adjusting screw until the specified dwell is obtained
as measured by a dwell meter. (See specifications.)
Alternate Method:
Turn the adjusting screw in (clockwise) until the engine
begins to misfire, then give the wrench one-half turn in the
opposite direction (counterclockwise) thus giving the ap-
proximate dwell angle required.
Removal of Distributor Cap
The cap is removed as shown in Figure 3. Place screw driver
in slot head of the hatch, press down and turn 1/4 of a turn in
either direction.
FIGURE 3—Distributor Cap Removal
Distributor Inspection and Checking
With the distributor removed from the vehicle, it is advisable
to place the distributor in a distributor testing machine or
synchroscope. When mounting distributor in tester, first
secure the gear in the drive mechanism, then push distributor
housing down toward the gear to take up end play between
the gear and housing, and finally secure the housing in the
tester. Test the distributor for variation of spark, correct
centrifugal and vacuum advance, and condition of contacts.
This test will give valuable information on the distributor
condition and indicate parts replacement which may be nec-
essary.
When checking the distributor condenser, it should be
checked with a reliable make of condenser tester. The con-
denser should be checked for the following properties.
Insulation Resistance (or Leakage, Series Resistance, Break-
down Test, and Capacity (mfd.).
Replacing Distributor Contact Set
The contact point set is replaced as one complete assembly
(Fig. 4). The BREAKER LEVER SPRING TENSION and
POINT ALIGNMENT on the service replacement contact
set are factory adjusted. Only the POINT OPENING requires
adjusting after replacement.
FIGURE 4—Removing Distributor Contact Set
Replacement of contact set is as follows:
Remove the two attaching screws (Fig. 4) which hold the
base of contact set assembly in place.
Remove the condenser lead and primary lead from the nylon
insulated connection by turning screw (Fig. 4) in contact set.
Replacement is the reverse of removal.
CAUTION: At time of assembly, make sure the
condenser lead and primary lead are located as in,
Figure 5.
Leads must be properly located to eliminate lead interfer-
ence between cap, weight base, and breaker advance plate.
Add a trace of Ball Bearing Lubricant to the breaker cam.
Adjusting Distributor Dwell Angle
Either of the following methods can be used to adjust the
dwell angle to the proper setting off the vehicle:
Screw Adjustment Method—Distributor Mounted in
Distributor testing Machine
Connect the dwell meter to the distributor primary lead.

8ELECTRICAL
Turn the adjusting screw to set the dwell angle to the proper
setting of degrees (Fig. 2). (See Test Specifications.)
Screw Adjustment Method Distributor Mounted in a
Vise
Connect a testing lamp to the primary lead.
Rotate the shaft until one of the circuit breaker cam lobes is
under the center of the rubbing block of the breaker lever.
Turn the adjusting screw (clockwise) as shown in Figure 2
until the lamp lights, then give the wrench one-half turn in
the opposite direction (counterclockwise) giving the proper
dwell angle.
Figure 5—Correct Routing and Attachment of
Primary Ignition and Condeser Leads
BATTERY SPECIFICTIONS
Make Auto-lite
Model 11-HS-60
Rating 60 Ampere Hours
No. of Plates (Each Cell) 11
GENERATOR SPECIFICATIONS
With
Air Conditioning Withoout Air Conditioning
Make \Delco-Remy \Delco-Remy
Model 1102070 1102018
Type Shunt Shunt
Rotation CW. @ Drive End CW. @ Drive End
Brush Spring Tension 28 Oz. 28 Oz.
Field Current 1.69-1.79 Amperes
@ 12 Volts, 80°F. 1.48-1.62 Amperes @ 12 Volts, 80°F.
Cold Output 35 Amperes @ 14.0
Volts, 2510 R.P.M. 30 Amperes @ 14.0 Volts, 2210 R.P.M.

ELECTRICAL 9
VOLTAGE AND CURRENT REGULATION
With
Air Conditioning Without Air Conditioning
Make Delco-Remy Delco-Remy
Model 1119168 1119003
Cutout Relay Closing Voltage 11.8-13.5 11.8-13.5
Air Gap .020" .020"
Point Gap .020" .020"
Voltage Regulator Volts 13.8-14.8 13.8-14.8
Air Gap .075" .075"
Current Regulator Amperes 32-37 27-33
Air Gap .075" .075"
STARTING MOTOR SPECIFICATIONS
Make Delco-Remy
Model 1107648
Brush Spring Tension 35 Oz. Min.
No Load Test Amperage Draw 75 Maximum
Volts 10.3
R.P.M. 6900
SOLENOID SWITCH
Model 1119760
Hold-in Winding 18-20 Amperes at 10 Volts
Both Windings 72-76 Amperes at 10 Volts

10 ELECTRICAL
DISTRIBUTOR SPECIFICATIONS
Make Delco-Remy
Model 1110887
Rotation L.H. CCW.
Point Opening .016"
Cam Angle 28°-32° (Set to 30° )
Breaker Lever Tension 19-23 Ozs.
Condenser Capacity .18-.23 Mfd.
Centrifugal Advance
(Engine Degrees and R.P.M.)
Start
Intermediate
Intermediate
Maximum
0-4°
15-19°
24-28°
34-38°
700 R.P.M.
1550 R.P.M.
2600 R.P.M.
3800 R.P.M.
Vacuum Control
(Engine Degrees and Inches
Mercury)
Start
Full Advance
Maximum Engine Degrees
1116117 Delco-Remy
5"-7"
14.25-15.75
20°
SPARK PLUG SPECIFICAITONS
Make Auto-lite Champion
Model AL-7 H-10
Thread 14 M.M. 14 M.M.
Gap .035" .035"
Torque 30 Ft. Lbs. 30 Ft. Lbs.

ELECTRICAL 11
BULB CHART
Trade Number
and
Candle Power American Motors Part Number Location
57
2 C.P. 127934 Glove Box and Hood Ornament Emblem
57
2 C.P. 127934 Instrument Illumination Clock
Head Lamp Beam Indicator
Directional Signal Indicator
Generator Charge Indicator
Oil Pressure Signal
1488
2 C.P. 3145931 Selector Lever Indicator Light
67
2 C.P. 142450 License
89
6 C.P. 142452 Dome and Courtesy Light
1034
32 & 4 C.P. 454645 Tail, Stop, and Direction Part and Direction
1073
32 C.P. 454646 Back-Up
5400
50 & 40W 456796 Head Light

12
FUEL———CARBURETION
CARTER MODEL WCFB-2593-S FOUR-BAR-
REL CARBURETOR
The Carter Model WCFB carburetor is basically two (2)
dual carburetors contained in one assembly. The section
containing the metering rods, accelerating pump and
choke is termed the primary side of the carburetor, the
other section, the secondary side. It has five (5) conven-
tional circuits. They are:
2—Float Circuits
1—Low Speed Circuit
2—High Speed Circuits
1—Pump Circuit
1—Climatic ® Control (Choke) Circuit
FLOAT CIRCUITS
The purpose of the float circuits is to maintain an adequate
supply of fuel at the proper level in the bowls for use by
the low speed, high speed, pump and choke circuits. Pri-
mary and secondary bowls are separated by a partition.
The fuel line connection is on the primary side. Fuel is
supplied to the primary and secondary intake needles and
seats through a passage in the bowl cover. There are two
fine mesh strainer screens in the bowl cover. They are
located at the fuel inlet and at the secondary intake needle
seat.
The bowls are vented to the inside of the air horn by
vertical vent tubes and to atmosphere by drilled passages
in the air horn. Bowl vents are calibrated to provide proper
air pressure above the fuel at all times. The bowl cover
gasket seals the fuel bowl, idle and vacuum passages. To
assure a positive seal, always Use a new bowl cover gasket
when reassembling. An air leak at this point can result in
a performance or economy complaint.
A connecting passage along the outside of the body
effects a balance of the fuel levels and air pressures be-
tween the two bowls.
FIGURE 1—Float Circuit
LOW SPEED CIRCUITS
Fuel for idle and early part throttle operation is metered
through the low speed circuit.
Fuel enters the idle wells through the metering rod jets
on the primary side of the carburetor. No idle system is
used in the secondary side of the carburetor.
The low speed jets measure the amount of fuel for idle
and early part throttle operation. The air by-pass, econo-
mizers, and idle air bleeds are carefully calibrated and
serve to break up the liquid fuel and mix it with air as it
moves through the passages to the idle ports and idle
adjustment screw ports. Turning the idle adjustment
screws toward their seats reduces the quantity of fuel
mixture supplied by the idle circuit.
The idle ports are slot shaped. As the throttle valves are
opened more of the idle ports are uncovered allowing a
greater quantity of the fuel and air mixture to enter the
carburetor bores. The secondary throttle valves remain
seated at idle.
FIGURE 2—Low Speed Circuit
Throttle Bore Vapor Vent Passages
Under certain conditions of high, under-hood temperature,
fuel vapor forms in the throttle bores when the engine is
not operating. This vapor accumulation may retard hot
engine starting until sufficient air is drawn into the carbu-
retor to mix with the vapor to form a combustile mixture.
The throttle bore vapor vent passages vent the bores
above the throttle valves to cavities in the underside of the
carburetor flange. Air is admitted to these cavities through
openings in the flange gasket. The air supplied by these
vent passages, when mixed with the accumulated vapor,
forms a more combustible mixture. This improves hot
engine starting.
HIGH SPEED CIRCUITS
Fuel for part throttle and full throttle operation is

FUEL—CARBURETION 13
supplied through the high speed circuits. Main discharge
nozzles are permanently installed and must not be re-
moved in service.
Primary Side
The position of the metering rods in the metering rod jets
control the amount of fuel flowing in the high speed circuit
of the primary side of the carburetor. The position of the
metering rods is dual controlled; mechanically by move-
ment of the throttle, and by manifold vacuum applied to
the vacuum piston on the vacumeter link.
Mechanical Metering Rod Action
During part throttle operation, manifold vacuum pulls the
vacumeter piston, link and metering rod assembly down,
holding the vacumeter link against the metering rod coun-
tershaft arm. Movement of the metering rods will then be
controlled by the metering rod countershaft arm which is
connected to the throttle shaft. This is true at all times that
the vacuum under the piston is strong enough to overcome
the tension of the vacumeter spring.
Vacuum Metering Rod Action
Under any operating conditions (acceleration, hill climb-
ing, etc.), when the tension of the vacumeter spring over-
comes the pull of vacuum under the piston, the metering
rods will move toward their wide-open throttle or power
position.
FIGURE 3—High Speed Circuit Metering Rods
Secondary Side
Fuel for the high speed circuit of the secondary side is
metered at the main metering jets (no metering rods used).
Throttle valves in the secondary side of the carburetor
remain closed until the primary throttle valves have been
opened a predetermined amount. They arrive at wide open
throttle position at the same time as the primary throttle.
Thisisaccomplishedbylinkagebetweenthethrottlelevers.
The second set of counterweighted off-set throttle
valves mounted above the secondary throttle valves are
called "auxiliary throttle valves." Air velocity through the
carburetor controls the position of the auxiliary throttle
valves. When the accelerator is fully depressed, only the
primary high-speed circuit will function until there is
sufficient air velocity to overcome the weight of the coun-
terweight on the auxiliary throttle lever and open the
auxiliary throttle valves. When this occurs, fuel will also
be supplied through the secondary highspeed circuit.
The secondary throttle valves are locked closed during
choke operation, to insure faster cold engine starting and
good "warm-up" performance.
Anti-Percolator
To prevent vapor bubbles in the nozzle passages and low
speed wells from forcing fuel out of the nozzles, anti-
percolator passages and calibrated plugs and bushings are
used. Their purpose is to vent the vapors and relieve the
pressure before it is sufficient to push the fuel out of the
nozzles and into the intake manifold. Anti-percolator
plugs and bushings are permanently installed and must not
be removed in service.
FIGURE 4—High Speed and Anti-Percolator
Circuits
PUMP CIRCUIT
The pump circuit is located only in the primary side of the
carburetor.

14 FUEL—CARBURETION
The accelerating pump circuit provides the measured
amount of fuel necessary to insure smooth engine opera-
tion during acceleration at speeds below approximately 30
MPH.
When the throttle is closed, the pump plunger moves
upward in its cylinder and fuel is drawn into the pump
cylinder through the inlet passage. The discharge needle is
seated at this time to prevent air being drawn into the
cylinder. When the throttle is opened, the pump plunger
moves downward forcing fuel out through the discharge
passage, past the discharge needle, and out of the pump
jets. When the plunger moves downward, the inlet valve is
closed preventing fuel from being forced back into the
bowl.
If the throttle is opened suddenly, the pump spring will
be compressed by the plunger shaft telescoping, resulting
in a smoother pump discharge of longer duration.
At speeds above approximately 30 MPH, pump dis-
charge is no longer necessary to insure smooth accelera-
tion. When the throttle valves are opened a predetermined
amount, the pump plunger bottoms in the pump cylinder
eliminating pump discharge.
FIGURE 5—Accelerating Pump Circuit
CHOKE CIRCUIT
The Climatic ® control circuit provides a correct mixture
necessary for quick cold engine starting and warm-up.
When the engine is cold, tension of the thermostatic coil
holds the choke valve closed. When the engine is started,
air velocity against the off-set choke valve causes the
valve to open slightly against the thermostatic coil tension.
Intake manifold vacuum applied to the choke piston also
tends to pull the choke valve open. The choke valve
assumes a position where tension of the thermostatic coil
is balanced by the pull of vacuum on the piston and air
velocity on the off-set choke valve.
FIGURE 6—Choke Circuit
FIGURE 7—Choke Housing Assembly
When the engine starts, slots located in the sides of the
choke piston cylinder are uncovered allowing intake man-
ifold vacuum to draw air heated by the exhaust manifold,
through the Climatic ® control housing. The flow of warm
air heats the thermostatic coil and causes it to lose some of
its tension. The thermostatic coil loses its tension gradu-
ally until the choke valve reaches wide open position.
When the engine is accelerated during the warm- up peri-
od, the corresponding drop in manifold vacuum allows the
thermostatic coil to momentarily close the

FUEL—CARBURETION 15
choke, providing a richer mixture.
During the warm-up period, it is necessary to provide a
fast idle speed to prevent engine stalling. This is accom-
plished by a fast idle cam which is rotated by a connector
rod attached to the choke shaft. The fast idle cam prevents
the primary throttle valves from returning to a normal
warm engine idle position while the Climatic ® control is
in operation.
During the starting period if the engine becomes flood-
ed, the choke valve can be partially opened manually. This
can be accomplished by depressing the accelerator pedal
to the floor and engaging the starter. The projection on the
throttle lever (unloader) will rotate the fast idle cam and in
turn partially open the choke valve.
OVERHAUL AND ADJUSTING
Flooding, stumbling on acceleration, and other perfor-
mance complaints in many cases are attributable to dirt,
water, or other contaminants in the carburetor. Therefore,
when removing a carburetor for inspection, do not drain
the fuel bowl. The contents of the carburetor may be
examined for evidence of contamination.
Whenever the carburetor is removed, use care when
handling to prevent damage to the throttle valves. The
lower edge of the throttle valves extend beyond the base of
the carburetor when in the open position.
Figure 8 illustrates the locations and relative lengths of
the air horn attaching screws.
FIGURE 8—Location and Lengths of Air Horn
Attaching Screws
Carefully remove the air horn assembly with the gasket
and attaching parts. If the gasket sticks to the body casting,
the floats may become bent.
The float needles and seats must not be interchanged,
therefore, group the needles and seats with their respective
float assemblies.
The accelerator pump discharge check needle is located
in the passage below the pump jet cluster and may be
removed by inverting the carburetor.
The primary metering rod jets have larger openings than
the secondary jets. Therefore, do not mix. the jets.
When cleaning the carburetor, follow the instructions
for the cleaning solution being used.
Do not use drills or wire to clean jets or ports, this may
result in inadvertent enlarging the openings or ports, af-
fecting carburetor performance.
ASSEMBLY PROCEDURE
Assembling Throttle Flange
Install primary and secondary throttle shafts.
Assemble throttle valves on shafts with trade mark (C)
toward idle ports on primary valves and away from center
of carburetor on secondary valves when viewed from the
bottom. (Use Oval head screws on secondary valves.)
Install idle mixture adjusting screws and springs finger
tight, then loosen one turn.
NOTE: Do not tighten mixture screws tighter than
finger tight.
Assemble secondary throttle return spring and throttle
lever on secondary throttle shaft. Install and tighten retain-
ing washer and screw.
Wind the return spring 11/2 turns and hook over secondary
throttle lever.
FIGURE 9—Assembling Secondary Throttle
Lever and Spring
Install primary shaft wave washer, inner throttle shaft
arm, and throttle shaft dog. Hook flex spring on outer
throttle lever and throttle shaft dog and install outer lever
on primary shaft. Install washer and screw.
Install primary to secondary connector rod using a flat
washer on each side of the levers and retain with pin
springs.

16 FUEL—CARBURETION
FIGURE 10—Primary Throttle Shaft Arm
and Lever Assembly
Assemble fast idle cam and spring assembly and lower
choke lever placing the assembly on the attaching screw.
FIGURE 11—Fast Idle Cam and Spring
Assembly
Place the secondary lockout lever against boss and
install the fast idle cam assembly in position on the boss.
The levers must operate freely.
FIGURE 12—Secondary Lockout and Fast
Idle Cam Assembled
Install auxiliary throttle shaft and auxiliary throttle
valves.
Using a new gasket, assemble the throttle flange on the
carburetor body. Assemble while holding auxiliary throttle
valves closed.
CAUTION: Tighten the screws indicated in Figure
13 securely to prevent leakage between the body
and throttle flange.
FIGURE 13—Location of Body to Flange
Screws-
Assembling Carburetor Body
Install the primary metering rod jets, (jets with the large
holes) in the accelerator pump side of the carburetor. Then
install the secondary main jets.
Install the two low speed jets in the primary side of the
body.
The steel pump inlet ball check and retainer is installed
in the bottom of the accelerator pump cylinder. A 5A6" six
point socket assists pressing into place.
Install pump passage screw plug and gasket.
The brass pump discharge check needle is installed
point down in the passage below the pump discharge jet
cluster.
Install the accelerator pump discharge cluster gasket
and cluster assembly.
Inspect vacumeter spring. The vacumeter spring affects
both economy and performance. If it appears damaged or
distorted, replace. If there is any doubt, compare it with a
new one. Place the spring in vacumeter bore.
Install lower pump spring in pump cylinder.
Assembling Air Horn
Using a new gasket, install the primary needle and seat;
then install secondary needle and seat assembly.

FUEL—CARBURETION 17
NOTE: Intake needles and seats are carefully
matched during manufacture. Do not use the pri-
mary needle in the secondary seat or vice versa. To
avoid unnecessary bending, both floats should be
reinstalled in their original positions and then
adjusted.
Setting the floats to, specifications assures an adequate
supply of fuel in the bowls for all operating conditions.
Float adjustments must be made with the bowl cover
gaskets removed and should be checked vertically
(specified distance between bowl cover and bottom of
floats) and laterally (sides of floats should just clear the
arms of gauge) . Correct lateral adjustment is important. If
the floats are misaligned, they may bind or drag against the
inner walls of the bowl.
LATERAL ADJUSTMENT—Place primary float
gauge T-109-232 and secondary float gauge T-109-222
under center of float with notched end of gauge fitted over
edges of casting. Sides of floats must just clear vertical
uprights of gauge. Adjust by bending arms.
FIGURE 14—Float Gauge in Position
VERTICAL ADJUSTMENT—Check with gauge in
position. Floats must just clear the horizontal part of the
gauge. There must be 1/8" between top of floats and air
horn for .primary and 3/16" for secondary floats. Adjust by
bending at center section of float arms.
FLOAT DROP ADJUSTMENT—Hold air horn assem-
bly in normal upright position and measure between the
top center of floats to air horn. It must be /8" for primary
and 11/16" for secondary floats. Adjust by bending tabs on
float brackets.
Remove float assemblies and install new air horn gasket.
Assemble vacumeter link and vacumeter piston with lip
on link toward air horn.
Insert accelerator pump plunger shaft in air horn and
FIGURE 15—Checking Float Drop
retain with link and pump arm assembly.
Reassemble floats.
Install air horn assembly on carburetor body. Be sure
vacumeter piston and pump plunger are properly aligned.
Do not bend float arms while assembling. Refer to Figure
8 for correct location of different length screws.
Insert metering rods, catching spring loop with lower
end before inserting. Start rods in jets; then twist eye of rod
to engage vacumeter link assembly.
Install countershaft return spring on countershaft.
The pump countershaft is inserted into the pump operating
arm and metering rod arm. Be sure metering rod arm is in
slot of vacumeter link.
Install idle vapor vent lever and screw; then tighten
pump arm screw.
Place washer on lower end of throttle connector rod.
Install rod into throttle lever while holding lever in closed
position and retain with spring and retainer.
Wind countershaft return spring one-half turn.
Install throttle connector rod in pump countershaft lever
and retain with pin spring.
Install choke housing onto air horn using a new gasket.
Assemble choke piston on link and install shaft and
piston, assembly through air horn while guiding piston in
cylinder.
Place choke valve in position on choke shaft in air horn
so that (C) is visible from the top. Center the valve and
tighten screws. Be sure valve or shaft does not bind and
valve opens freely of its own weight.
Position baffle plate on choke housing.
Install choke coil housing gasket on piston housing with
index mark on plastic housing at the bottom and retain
with three screws and retainers. Leave coil housing in this
position while making other adjustments.
Install choke operating levers on shaft. Tighten screw
only enough to permit lever to be moved.
The choke connector rod is installed in operating lever
and choke lower lever. Retain lower end with pin spring.
Install strainer plug, gasket, and strainer in primary side
and strainer plug and gasket on secondary side.

18 FUEL—CARBURETION
ADJUSTMENTS
Float Adjustment
Float adjustment is performed during assembly. "Refer to
Assembling Air Horn."
Pump Adjustment
Back out idle speed screw, hold choke in wide open
position, then close throttle valves tight in bores of carbu-
retor.
Flat on top of pump arm must be parallel with dust
cover gasket surface.
Bend throttle connector rod at lower angle to obtain
adjustment.
FIGURE 16—Accelerator Pump Adjustment
Metering Rod Adjustment
With throttle valves seated, press down on vacumeter link
until metering rods are bottomed.
Holding rods down with throttle valves seated, rotate
metering rod arm until it contacts lip on vacumeter link.
Tighten metering rod arm clamp screw.
Vapor Vent Adjustment
Lubricate countershaft with oil and install dust cover and
gasket.
With choke valve held in wide open position and throt-
tle valves seated, there should be I/32" between lower edge
of bowl vapor vent valve and dust cover. To adjust, re-
move dust cover and bend vapor vent arm.
Rotate choke coil housing in direction opposite arrow
until index mark on coil housing is aligned with center
index on piston housing. Tighten retaining screws.
With choke lever clamp screw loose, hold choke valve
closed.
Figure 17—Meteromg Rpd Adkist,em
Figure 18—Vapor Vent Adjustment
Place wire gauge T-109.189 .023" on boss. Rotate choke
leveronshaftuntiltangonfastidlecamcontactswiregauge