The test questions are designed to test knowledge and skills that are needed to repair school buses. When the low-air pressure warning fails to extinguish after startup it would mean that system pressure was not higher than 60 psi in either or both of the onboard circuits; after startup, the operator would have to attempt to build system pressure before making a judgment on whether there was a malfunction, so Technician A is wrong. Air is present in both the service and spring brake chambers. At the end of each practice test a scored quiz reinforces the material covered in the guide. Five types of multiple-choice questions exist on the tests. When a leak occurs at the cage bolt hole or key hole, this is caused by a leaking or tom hold-off diaphragm. When checking the stroke on an automatic slack adjuster, Technician A says replace the slack adjuster if the stroke is found to be over the legal limit.
The only adjustment on an air pressure governor is the cutout pressure, so if the cutout pressure is set correctly and the cut-in pressure is out of specification, the governor should be replaced. If the governor requires adjusting, remove the top cover from the governor and loosen the adjusting screw lock nut. Neither A nor B Answer C is correct. If you pass tests S1 through S7, and meet the minimum experience requirement, you will earn the certification of Master School Bus Technician. Neither A nor B While discussing the operation ofthe pressure-protection valve, Technician A says the valve is normally closed and opens at a pre-set pressure rating. The questions are designed to expose practical problems of diagnosis and repair encountered by technicians in their every-day work.
Both A and B D. Each question focuses on a specific diagnostic or repair problem and only one of the answers provided is correct. Technician B says that when replacing a slack adjuster, increasing the length is acceptable because it increases brake torque at the wheel. Which of the following is known as brake compounding? A build-up of moisture in the reservoirs decreases the volume of reserve air so each brake application will use up more of the volume available. When this valve opens, water and contaminants are expelled to the atmosphere. This will at least get you familiar with the material under consideration and also on the format of the exam.
The courses feature a detailed, three-tiered preparatory methodology practice, standard, and timed testing modes that are designed to ensure that users increase confidence in answering task-list based questions and when performing in a simulated, timed exam environment. Neither A nor B Answer C is correct. When performing an air pressure balance test the test gauges should be located at two corresponding brake chambers because the pressure is important but so is the timing of the delivery. Recheck the governor cut-in pressure to be sure this pressure is correct. Each question on the test is associated with a particular task or set of tasks in the task list.
Please review of the task lists, and judge whether you know how to perform each listed task. Master Technicians can specialize in auto repair, collision repair, medium-heavy trucks, school buses, transit buses, or truck equipment. Only after verifying that the foundation brake components and slack set-up are correct is when a technician should check for a defective automatic slack adjuster. Electronic testers, such as Vericom and Fraser, sense rate of speed change and then uses this data to calculate stopping distances and a mechanical tester such as Tapley meter is a pendulum device that measures deceleration but only saves a value that represents the maximum deceleration reached during the stop. Neither A nor B Answer C is correct. These articles, questions and comments are very time consuming so even a small donation gives me motivation to keep educating automotive owners.
It opens when the reservoir pressure reaches the governor pressure. If you improve your score by a few questions, you pass. You must first verify if the modulator valve solenoids are defective. All chambers are evacuated During a wheel seal repair, the brake friction facings are observed to be saturated with oil and glazed to a mirror finish. Spring brake chambers only C.
A loose control arm fastener would also increase the stroke. Technicians must either have 1 two years of on the job training or 2 one year of on the job training and a two-year degree in automotive repair. Both A and B D. God bless you for this. Because the vehicle is moving, it indicates the parking brakes are released meaning that there is air in the spring brake chambers; when the driver makes a service application, air is now charged to the service chambers. Technician B says the bus should be driven to 20 mph in a safe area and the brakes should be applied quickly and firmly but not to the point of wheel lock up. Technician A says that the problem may be caused by a loss ofone section of the dual system.
However, after becoming certified, you will be proud of yourself and you will be more confident when encountering school buses with difficult repair jobs. For this, they refer you to a list of third-party providers on their site. Certified technicians meet this customer expectation and, as a result, create a sense of quality in the eyes of the customer. Both A and B D. The spring brake chamber is only charged with air when the parking brakes are released. In the pictures above, Technician A says draining fluid from one side will drain all the gear oil from both differential and both planetary gear hub ends. Technician B says the air governor could be defective.
As soon as the pressure in the sump drops below the pressure at the S port the valve closes. Automotive Service Excellence, in conjuction with the U. Next, all new questions are pre-tested and checked for quality on technicians all around the country. This post was written by: Martin Hand Donations If you find this information helpful please consider a donation. At the end of each explanation, the next button returns you directly to the next question on the test. Simultaneous application ofservice and spring brake forces to the foundation brakes When discussing quick-release valve diagnosis, Technician A says that when the service brakes are applied, the quick-release valve exhaust port should be closed.
If this adjusting screw is rotated clockwise, the cutout pressure is decreased. Water and contaminants are carried with the air into the valve sump. Faulty valves will usually cause airflow problems and air leaks at the valve. Also, since I am just going to be teaching myself everything for the exam, what are some books you could personally suggest to me to read or have with me? Each question type has different instructions. A damaged service diaphragm would create a leak at the pushrod hole.