Page 14 - Driving Commercial Vehicles Manual

S-cam brakes — automatic slack adjuster .................................................. 191
Checking and adjusting automatic slack adjusters ................................... 191
Slack adjusters with hexagonal adjusting bolts .................................... 192
Slack adjusters with square adjusting bolts .......................................... 193
Air brake adjustment myths ........................................................................ 193
Review questions .......................................................................................... 194

Chapter 10: vehicle and air brake pre-trip inspections ............................ 195
What you’ll learn........................................................................................... 195
You’re responsible ....................................................................................... 195
Vehicle condition ......................................................................................... 196
Cargo securement ...................................................................................... 196
Written report requirements ...................................................................... 197
Pre-trip inspection report for your road test ............................................ 197
Conducting a pre-trip inspection ............................................................... 199
Before you begin ....................................................................................... 199
Tractor-trailer combination pre-trip inspection — Class 1 ......................... 200
1. Under hood ....................................................................................... 201
2. In cab ................................................................................................. 202
3. Air brake system test ........................................................................ 204
4. Circle check for lights ........................................................................ 205
5. Mechanical circle check .................................................................... 205
6. Brake response, tug and steering wheel slack tests ......................... 209
Single unit truck pre-trip inspection — Class 3 .......................................... 210
1. Under hood ....................................................................................... 211
2. In cab ................................................................................................. 212
3. Air brake system test ......................................................................... 214
4. Circle check for lights ........................................................................ 214
5. Mechanical circle check .................................................................... 215
6. Brake response, tug and steering wheel slack tests ......................... 217
Bus pre-trip inspection — Class 2 or Class 4 (unrestricted) ...................... 218
1. Engine compartment ........................................................................ 219
2. In cab ................................................................................................. 220
3. Circle check ....................................................................................... 222
4. Passenger compartment check ......................................................... 224
5. Brake response, tug and steering wheel slack tests ......................... 224
Passenger vehicle pre-trip inspection — Class 4 (restricted) ..................... 225
1. Under hood ...................................................................................... 225
2. In passenger compartment ............................................................... 226
Start engine, check the following: ........................................................ 226
3. Circle check ...................................................................................... 227
4. Brake response tests ........................................................................ 228

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