10
Small Gas Engines
Governor Throttle Controls 187
What an Engine Governor Does 187
Types of Governors 188
Governor Features 192
C H A P T E R 1 0
Ignition Systems
195
Basic Ignition System Operation 195
Ignition System Components 196
Ignition Coil 197
Spark Plugs 197
Spark Plug Wire 200
Switching Devices 200
Magneto Ignition Systems 201
Operation of Capacitive Discharge Ignition
(CDI) System 202
Operation of Transistor-Controlled Ignition (TCI)
System 203
Operation of the Mechanical Breaker Point
Ignition (MBI) System 205
Magneto Ignition Systems for Two-Cylinder
Engines 208
Battery Ignition Systems 208
Auto-Transformer–Type Ignition Coil 210
The Lead-Acid Battery 210
The Discharging/Charging Cycle 211
C H A P T E R 1 1
Lubrication Systems
215
Principles of Lubrication 215
Friction 215
Qualities of Lubricating Oil 216
Permits Easy Starting 216
Lubricates and Prevents Wear 216
Protects Against Rust and Corrosion 217
Keeps Engine Parts Clean 217
Cools Engine Parts 218
Seals Combustion Pressures 218
Prevents Foaming 218
Aids Fuel Economy 218
Oil Specifi cations 218
SAE Viscosity Grade 218
API Engine Oil Service Classifi cation 219
Selecting the Proper Engine Oil 220
Engine Lubrication Systems 221
Two-Cycle Engine Lubrication 221
Four-Cycle Engine Lubrication 222
Oil Filter Systems 225
Low-Oil Warning and Shutdown Systems (LOS) 227
C H A P T E R 1 2
Cooling Systems
231
Principles of Engine Cooling 231
Air Cooling 232
Liquid Cooling 233
Pressurized Cooling Systems 233
Outboard Engine Cooling Systems 235
S E C T I O N 4
Engine Service
C H A P T E R 1 3
Preventive Maintenance and
Troubleshooting
243
Preventive Maintenance 243
Engine Cleaning 243
Checking Oil Level and Condition 244
Changing Oil 245
Lubricating Cables and Linkage 246
Spark Plug Service 247
Air Cleaner Service 248
Crankcase Breather Service 249
Muffl er Service 250
Battery Service 251
Pressurized Liquid Cooling System Service 252
Maintaining Outboard Cooling Systems 252
Storing an Engine 253
Systematic Troubleshooting 254
Check the Easiest Things First 254
Verify the Fundamental Operating
Requirements 254
Checking RPM 255
Testing Compression 256
Testing Differential Pressure 257
Service Information 258
Engine Identifi cation 258
S E C T I O N 4
Engine Service