Harley Davidson motorcycles 1940 to 1947 inclusive O.H.V. engine / side valve engine. Service Manual — page 1

SERVICE MANUAL

APPLYING TO THE FOLLOWING HARLEY-DAVIDS ON MOTORCYCLES — 1940 to 1947 INCLUSIVE

O.H.V. Engine Models

61 Cu. In. (1000 c.c.) 74 Cu. In. (1200 c.c.)

Side Valve Engine Models

74 Cu. In. (1200 c.c.) 80 Cu. In. (1300 c.c.)

SECTIONAL INDEX
TROUBLE CHART Pages 6 to 8
INITIAL SERVICING OF NEW

MOTORCYCLE

Pages 10 and 11
ENGINE LUBRICATION Pages 30 to 36
ENGINE OVERHAUL Pages 37 to 91
ELECTRICAL SYSTEM Pages 92 to 118
SERVICING CARBURETOR Pages 119 to 125
TRANSMISSION AND CLUTCH, Pages 126 to 146
WHEELS, HUBS AND * TIRES. Pages 147 to 153
FORK, FRAME AND HANDLEBARS, Pages 153 to 158
SIDECAR Pages 162 and 163
DETAILED INDEX Pages 164 and 165

FOREWORD
This Service Manual is dedicated to attaining for Harley-Davidson motorcycle owners the highest degree of performance and satisfaction.

Except when a particular model or year model is indicated, the information in this manual applies to both, O.H.V. and Side Valve Models, 1940 to 1947, and in a general way to Big Twin Models back to 1937.

To others than Harley-Davidson dealers and their mechanics. If you have any questions pertaining to service information in this manual, or special tools mentioned, see your Harley-Davidson dealer. Index

Air Cleaner Assembly Illustration. . . . . . 10

Air Cleaner, (Mesh Pack Type). . . . . . . ..10

Air Cleaner, (Oil Bath Type). . . . . . . . ..10

Alignment Fork, Frame and Handlebar. . . . 156

Aligning, Gas Sbut-ofi Valve Fittings. . . . . 163

Battery, Care of. . . . . . . . . . . . . . ..106

Bearings, Engine Main. . . . . ..59, 60

Bearings, Connecting Rod Lower. . . .60,61

Brake, Front Wheel, Assembly Illustration. . . 18

Brake, Rear Wheel, Assembly Illustration. . ..19

Brake, Front and Rear Wheel Assembled,

illustration . . . . . . . . . . . . . . . . 20

Brakes, Adjusting . . . . . . . . . . . . . ..20

Brakes, Servicing . . . . . . . . . . . . . ..20

Breather Valve, Timing (Side Valve Engine). 70

Bushings, Connecting Rod Upper. . . . . . ..90

Bushings, Cam Gear Shaft —

OJ1.V. Engine. . . . . . . . . . . . . . ..53

Side Valve Engine. . . . . . . . . . . . ..54

Carburetor, Adjusting . . . . . . . . . . . ..21

Carburetor, Servicing. . . . . . . . . . . . 120

Chains, Adjusting . . . . . . . . . . . . . ..12

Chains, Lubricating . . . . . . . . . . . . ..12

Chains, Repairing . . . . . . . . . . . . . ..14

Circuit Breaker Assembly Illustrations. . 80,81

Circuit Breaker, Removing —

OJf.V. Engine. . . . . . . . . . . . . . ..43

Side Valve Engine. . . . . . . . . . . . ..44

Circuit Breaker. . . . 43, 44, 79, 80, 81, 82

Circuit Breaker, Servicing . . . . . . . . . ..80

Circuit Breaker, Installing and Timing Ignition.81, 82

Clutch Assembly Illustration. . . . . 146

Clutch, Spring Tension, Adjusting. . . . . . 16

Clutch, Disassembling . . . . . ..16,17

Clutch, Reassembling . . . . . . . . . . . ..17

Clutch Control, Checking and Adjusting. . . 15

Clutch Hub, Removing . . . . . .. 136

Clutch, Installing . . . . . . ... 142

Commutator, Cleaning. . . . . . . . . . . ..103

Connecting Rods, Aligning. . . . . . . . . ..83

Control Cable, Front Brake, Replacing. . ..26

Control Wire, Throttle and Spark, Replacing. 25

Crankcases, Assembling. . . . . . . . . . ..63

Cylinders, Reboring and Rehoning. . . . . . 45

Cylinder Head Assembly Illustration

(o.h.v. engine—rear head). . . . . . . . . 50

Cylinder Heads, Servicing (O.H.V. Engine). 37, 52 Cylinders, Installing —

O.H.V. Engine. . . . . . . . . . . . . . ..84

Side Valve Engine. . . . . . . . . . . . ..85

Cylinder Heads Installing —

O.H.V. Engine. . . . . . . . . . . . . . ..86

Side Valve Engine. . . . . . . . . . . . ..87
Page

Electrical System. . . . . . . . . . . . . . 96

Engine Overhauling . . . . . . . 37

Engine, Disassembling for Top Overhaul Only —

ОДУ. Engine . . . . . . . 37

Side Valve Engine. . . . . . . ..40

Engine, Removing (Assembled). . . . . . . ..41

Engine, Disassembling for Complete Overhaul —

OJi.V. Engine . . . . . . . 43

Side Valve Engine. . . . . . . 43

Engine, Fitting and Reassembling . . . . . . 45

Engine, Installing . . . . . . . . . . . . . ..87

Engine, Starting . . . . . . . . . . . . . . 5

Engine, To Stop. . . . . . . . . . . . . . ..5

Engine, Running in New. . . . . . . . . . ..5

Engine Serial Number . . . . . . . 3

Flutter Valve, Servicing (Side Valve Engine). 54

Flywheels, Servicing and Installing Crank Pin.. 60

Flywheels, Assembling . . . . . . . . . . . 61

Flywheels, Truing . . . . . . . . . . . . . 62

Forks, Removing and Installing . . . .. 153

Gear Ratios, Standard . . . . . . . . . . . ..4

Gear Shifter Control, Checking and Adjusting.. 14

Generator Assembly Illustrations. . . .92, 94

Generator, Removing. . . . . . . . . . . . 97

Generator, Testing. . . ...97 to 99, and 101

Generator, Disassembling . . . . . . . . . . 99

Generator, Reassembling . . . . . 102

Generator, Installing . . . . . ..64, 103

Generator Charging Rate. . . . . . 103

Handlebar Controls, Servicing. . . . . . . . 25

Handlebars, Straightening. . . . . 158

Handlebar Grip Assembly Illustration. . . . ..25

Headlamp, Adjusting . . . . . . 110

High Speed Tips. . . . . . . . . . . . . . ..6

Horn . . . . . . . . . ... 110

Ignition Coil. . . . . . . . 107

Ignition Timing—by Piston Position. . . . . ..86

Lamp Bulbs. . . . . . . . . Ш

Legend for o.h.v. engine oiling and breather

system . . . . . . . . ... 30

Lubrication, Commutator End Armature Bearing 105

Lubricants—Types to Use. . . . . . . . . . 9

Lubrication Chart . . . . . . . . . . . . . ..9

Lubrication, Engine. . . . . . . . . . 33

Lubrication, General . . . . . . . . . . . ..8

Lubrication, Transmission . . . . . 144

Maintenance, Regular Interval Inspection. . . ..11

Motorcycle—Initial Servicing. . . . . . . . ..10

Oil Pump, Removing (O.H.V. Engine). . 28, 43

Oil Pump, Servicing (O.H.V. Engine). . .71, 72 Oil Pump, Installing (O.H.V. Engine). . ..28,73

Oil Feed Pump, Removing (Side Valve Engine). 29,43 Oil Feed Pump, Servicing (Side Valve Engine).72,73 Oil Feed Pump, Installing (Side Valve Engine).29,79
Oil Scavenger Pump, Removing (side valve

engine) . . . . . . . . . . . . . . . . . 44

Oil Scavenger Pump, Servicing (side valve

engine) . . . . . . . . . . . . . . . . . 69

Oil Scavenger Pump, Installing (side valve

engine) . . . . . . . . .. 70

Oil Feed Pump, Adjusting. . . . . 28

Oil Pump Assembly Illustration (O.H.V. Engine) 66 Oil Feed Pump and Scavenger Pump Assembly illustration (side valve engine). . . . . . . 68

Piston Rings . . . . . . . . . . . . . . . . 89

Pistons, Fitting Oversize. . . . . . . . . . ..45

Pistons, Removing and Installing. . . . . . . 88

Piston and Ring Service. . . . . . . . . . . 87

Push Rod Cover Assembly Illustration. . . . ..23

Push Rod Cover Cork Washers, Installing. . ..23

Regulator, Current and Voltage. . . ... 106

Relay, Cut-Out. . . . . . . .. 105

Ride Control Assembly Illustration. . . 160

Saddle Spring Post Assembly Illustration. . . 27

Saddle Spring Post, Servicing. . . . . . . . 26

Shock Absorber Assembly Illustration. . . 159

Sidecar . . . . . . . . . 162

Signal Lights, Instrument Panel. . . . . . . . 5

Spark Plugs . . . . . . . . 108

Spark Plug Cables, Replacing. . . . . 107

Specifications, Carburetor. . . . . 125

Specifications, General . . . . . . . . . . . 3

Specifications, Engine . . . . . . . . . . . ..91

Specifications, Transmission . . . . . 145

Speedometer Head and Drive Core, Removing

and Installing . . . . . . ... 161

Steering Damper. . . . . . . . . . . . .24

Switch, Ignition-Light, Servicing . . . . 110

Switch, Ignition-Light, Assembly Illustration... 109

Tank Capacities, Gasoline and Oil. . . . . . ..4

Timing Gears, Installing —

OM.V. Engine. . . . . . . . . . . . . . ..78

Side Valve Engine. . . . . . . . . . . . ..78

Timing Mark, Flywheel —

O.H.V. Engine. . . . . . . . 79

Side Valve Engine. . . . . . . 79
Page

Tire Inflation Pressures. . . . . . . . . . . ..3

Tires and Tubes, Removing and Installing. .. 152

Transmission and Clutch, Overhauling. . 126

Transmission Assembly Illustrations. 128,130,132,134

Transmission, Removing . . . . . . 126

Transmission, Disassembling . . . . . 136

Transmission, Assembling . . . . ... 139

Transmission, Installing . . . . . .. 142

Trouble Chart. . . . . . . . . . . . . . . ..6

Valve Guides —

O.H.V. Engine. . . . . . . . . . . . . . ..46

Side Valve Engine. . . . . . . . . . . . ..46

Valves . . . . . . . . . . . . . . . . . . ..46

Valve Seats. . . . . . . . . . . . . . . . ..47

Valve and Valve Seats, Grinding and Testing.. 47

Valves, Installing. . . . . . . . . . . . . . 48

Valve Springs . . . . . . . . . . . . . . . 48

Valve Tappets, Adjusting —

O.H.V. Engine . . . . . . . 22

Side Valve Engine. . . . . . . . . . . . ..23

Valve Tappets and Valve Tappet Guides. . . ..58

Wheel Hub Assembly Illustrations. . 148,149

Wheels, Removing and Installing. . . .. 147

Wheel, Spoking . . . . . . . 150

Wheel, Truing . . . . . . . .. 150

Wheels, Hubs and Tires. . . . . .. 147

Wheel and Tire Care. . . . . . . 149

Wiring Diagram: Without current and voltage

regulator—1946 and earlier models . . . 114

Wiring Diagram: With current and voltage

regulator—1946 and earlier models . . . 112

Wiring Diagram: Generator-battery; ignition; horn; generator and oiling system signal

lights and stop lamp—1947 models. . .. 115

Wiring Diagram: Lighting system and horn—

1947 models . . . . . . . .. 116

Wiring Diagram: Lighting system accessory lamps (except police pursuit lamps—1947

models . . . . . . . . ... 118

Wiring Diagram: Generator—current and voltage regulator—battery; speedometer hand lock; police pursuit lamps and radio type

coil—1947 models. . . . . . . 117

Wiring Diagram: 1940 to early 1947 model

sidecar . . . . . . . . ... 162

Wiring Diagram: Later 1947 Model Sidecar. . 163