How do you test air brakes on a school bus?
Start the bus and let the air pressure build to at least 90 psi. Step on the brake pedal and put the bus into gear. Slowly take your foot off the brake and gently press the accelerator. The bus should not move.
How do air brakes on a school bus work?
Air brakes work using compressed air instead of hydraulic fluid. Air brakes can be either drum brakes or disc brakes, or a combination of both. Air is pressurized by an engine-mounted compressor. The air compressor then pumps the air into the air storage tanks, which store the compressed air until it’s needed.
How many steps are used in checking the air brake system?
The most important part of the pre-trip inspection is the 7 step air brake test.
How long should it take to build air pressure?
Air pressure build-up from 85 psi to 100 psi should take 45 seconds or less. While driving, observe the air pressure gauge during build-up to ensure proper air system operation. braking, pull over at a safe place and perform the 2 minute / 5 psi leakage test.
What is the first step of the air brake test?
Before starting the air brake test, park the vehicle on a flat surface, apply spring brakes and wheel chokes. Start testing with the low air warning device.
What are the main parts of air brake?
The Parts of an Air Brake System
- 1 – Air Compressor. The air compressor pumps air into the air storage tanks (reservoirs).
- 2 – Air Compressor Governor.
- 3 – Air Storage Tanks.
- 4 – Air Tank Drains.
- 5 – Alcohol Evaporator.
- 6 – Safety Valve.
- 7 – The Brake Pedal.
- 8 – Foundation Brakes.
At what PSI do air brakes lock up?
It will not stay in place until the pressure in the system is above 60 psi. On large buses it is common for the low pressure warning devices to signal at 80-85 psi. Drivers behind you must be warned when you put your brakes on.
What is a school bus endorsement?
A school bus endorsement requires you to be able to load and unload children, properly operate the lights, stop signs, and other warning devices on the school bus, and other needs specific to transporting children on a pre-determined bus route to and from their homes and their school.
What is an air brake endorsement?
An Air Brake Endorsement on your driver’s licence is a special citation that allows a driver to operate a vehicle equipped with an air brake system. To get an Air Brake Endorsement, drivers must complete a 16-hour ICBC -approved Air Brake Course.
What is a static brake test?
A static brake check tests features which the moving/rolling brake check doesn’t. 1. Before you start the engine: Make sure the hand/parking brake is on. Pump the footbrake pedal a few times until it becomes firm (this removes the vacuum in the brake servo unit) and maintain the footbrake pressure.