pressure to operate the bus. here. Not just because I've been in the truck world too long either. (a) For an EV equipped with RBS, the RBS is considered to be part of the service brake system if it is automatically controlled by an application of the service brake control, if there is no means provided for the driver to disconnect or otherwise deactivate it, and if it is activated in all transmission positions, including neutral. The CamLaster brake has 2 key design differences over traditional S-cam brakes. Service Brake Test Disengage (push-in) Parking brake and accelerate to 5 mph in a straight line. Heres how to test your hydraulic brakes for leaks: 1. A course for truck, bus & RV drivers operating a vehicle fitted with air brakes. S5.1.3.1 The service brakes on a vehicle equipped with one or more brake power assist units or brake power units, with one such unit inoperative and depleted of all reserve capability, shall be capable of stopping a vehicle from 60 mph within the corresponding distance specified in column IV of table II. S-cam brakes, on the other hand, require an external slack adjuster. S5.6 Brake system integrity. <<2aa158b17c19dd4986e8916ee1bbfc56>]>> 56 13 Check the fluid level in the hydraulic brake reservoir. OEM-specified brake lining and pads are recommended when replacement is necessary. Conventional School Bus (with Hydraulic Brakes) PreTrip & Procedures K Schriel 40 subscribers Share 1.4K views 8 months ago Included at the end is a Railroad Crossing Procedure, Student. Initial brake temperature means the average temperature of the service brakes on the hottest axle of the vehicle 0.2 mi before any brake application. For EVs having a manual control for setting the level of regenerative braking, the manual control, at the beginning of each burnish procedure, is set to provide maximum regenerative braking throughout the burnish. Our practice tests are designed to help you learn the material in the CDL Handbook, Each question is multiple choice and will provide instant feedback. Medium-duty vehicles (buses, straight trucks) can be ordered with either air or hydraulic. Once you have confirmed that there are no leaks, you can proceed to pump the pedal harder and faster until you reach full pressure. formatting. With transmission in neutral (or declutched) make 10 snubs from 40 to 20 mph at 10 fpsps for each snub. Some people will disagree with me. (b) Any visible brake fluid or lubricant on the friction surface of the brake, or leakage at the master cylinder or brake power unit reservoir cover, seal and filler openings. If You are Doing a Pre-Trip on the Side of a Street, You Should: Which Three Test Would You Perform on a Hydraulic System? Use the navigation links in the gray bar above to view the table of contents that this content belongs to. If everything looks good so far, its time to test-drive your vehicle. Beats leaf springs all to hell. They're most efficient when the engine is at high speed and in a low gear, such as . Is it true that air brakes cost less to maintain? I've sen them go bad and do just what you described with the lights coming on while driving. 3. For this you will need to know the parts of a single and dual air brake system, how to inspect and use them. Maintain control force until vehicle has stopped. Hydraulic or Air Brakes? To drive a vehicle with air brakes, you must pass the air brake component of the Georgia CDL knowledge test. For all other tests during all decelerations, the transmission selector is in the control position, other than overdrive, recommended by the manufacturer for driving on a level surface at the applicable test speed. 7 . Make six stops from 60 mph with vehicle at lightly vehicle weight, or at the manufacturer's option for a vehicle with GVWR greater than 10,000 pounds, at lightly loaded vehicle weight plus not more than an additional 1,000 pounds for a roll bar structure on the vehicle. If the vehicle does not remain stationary, reapplication of the service brake to hold the vehicle stationary, with reapplication of a force to the parking brake control at the level specified in S7.7.1.3 (a) or (b) as appropriate for the vehicle being tested (without release of the ratcheting or other holding mechanism of the parking brake) may be used twice to attain a stationary position. Repeat S7.5. After each snub, accelerate at maximum rate to 40 mph and maintain that speed until making the next brake application at a point 1.5 mi from the point of the previous brake application. guide. 571.105 Standard No. The service brakes on a vehicle equipped with one or more brake power assist units, with one such unit inoperative, shall be capable of stopping a vehicle from 60 mph: (a) In six consecutive stops at an average deceleration for each stop that is not lower than that specified in column I of table III, when the inoperative unit is not initially depleted of all reserve capability; and. Park your car on level ground and set the parking brake. Apply and hold the service brakes for a minute. Allow a braking distance interval of 1 mi. The performance requirements of S5 shall be met under the following conditions. 0000001241 00000 n Place bus in Neutral and set parking brake. S5.1.4 Fade and recovery. The third test is a leaks check. If the vehicle cannot attain a speed of 40 mph in 1 mph, continue to accelerate until the vehicle reaches 40 mph or until the vehicle has traveled 1.5 miles from the initial point of the previous brake application, whichever occurs first. Subscribe to: Changes in Title 49 :: Subtitle B :: Chapter V :: Part 571 :: Subpart B :: Section 571.105. a. Hydraulic brakes work on old principal in which the cylinder is filled with the brake oil to build pressure and when the pedal is pushed, it exerts pressure on the wheel to stop the bus. The service brakes of a vehicle equipped with one or more brake power assist units or brake power units with a backup system, with one brake power assist unit or brake power unit inoperative and depleted of all reserve capability and with only the backup system operating in the failed subsystem, shall be capable of stopping the vehicle from 60 mph in 15 consecutive stops at an average deceleration for each stop that is not lower than 12 fpsps (equivalent stopping distance 323 feet). It keeps kids more active. Disc brake systems use a two-piston sliding caliper at the steer axle and drive axle; older buses may utilize a single-piston caliper. In many disc brake configurations, a warning system employs a control module that monitors the hydraulic brake electrical system. OEM-standard lubricants are the best choice for this application because they're designed to meet tough duty standards, like school buses. Backup system means a portion of a service brake system, such as a pump, that automatically supplies energy, in the event of a primary brake power source failure. Reverse Lights - clean, not missing or broken . If its low, that could indicate a leak as well. The vehicle is loaded to GVWR for these tests and the transmission is in the neutral position when the service brake control is actuated and throughout the remainder of the test. Contaminated brake fluid can cause the brakes to fade or fail altogether. Advanced Member, BJ Henderson (b) If a single common indicator is used, the lamp shall display the word Brake. (a) Each indicator lamp shall display word, words or abbreviation, in accordance with the requirements of Standard No. Air brakes are more powerful, and have the spring-applied failsafe that will stop the bus in most brake failure situations. If instrument repair, replacement, or adjustment is necessary, make not more than 10 additional stops or snubs after such repair, replacement, or adjustment. Went there for test drive with another tech and connected laptop. I have a bus with air brakes and just bought one with hydraulics so i'll soon know the pros and cons of both! Linings are assumed adjusted for normal operating clearance in the released position. Third effectiveness (lightly loaded vehicle), 10. On vehicles with brake power assist units, render the brake power assist unit inoperative, or one of the brake power assist unit subsystems if two or more subsystems are provided, by disconnecting the relevant power supply. If the speed attainable in 2 miles is not less than 84 mph, a passenger car, or other vehicle with a GVWR of 10,000 lbs., or less, shall also be capable of stopping from 80 mph within the corresponding distance specified in column I of table II. multiple choice questions that will test your understanding of terminology. Mounts & Chargers. S5.1.5.2 (a) After being driven for 2 minutes at a speed of 5 mph in any combination of forward and reverse directions through a trough having a water dept of 6 inches, each vehicle with a GVWR of 10,000 pounds or less shall be capable of making five recovery stops from 30 mph at ten fpsps for each stop with a control force application that falls within the following maximum and minimum limits: (1) A maximum for the first four recovery stops of 150 pounds, and for the fifth stop, of 45 pounds more than the average control force for the baseline check (but in no case more than 90 pounds, except that the maximum control force for the fifth stop in the case of a vehicle manufactured before September 1, 1976, shall be not more than plus 60 pounds of the average control force for the baseline check (but in no case more than 110 pounds). Visually inspect the brake pad lining by checking each visible end and look through the opening of the caliper. They usually always have air ride suspension on the rear that auto levels to what is needed. S5.1.5.1 The control force used for the baseline check stops or snubs shall be not less than 10 pounds, nor more than 60 pounds, except that the control force for a vehicle with a GVWR of 10,000 pounds or more may be between 10 and 90 pounds. This standard applies to multi-purpose passenger vehicles, trucks, and buses with a GVWR greater than 3,500 kilograms (7,716 pounds) that are equipped with hydraulic or electric brake systems. This contact form is only for website help or website suggestions. AIR BRAKES PRACTICE TEST- A 1. Pump the brakes until the . S7.11 Service brake system - first fade and recovery test. Apply the brake control as quickly as possible. (g) For an EV with RBS that is part of the service brake system, failure of the RBS. Hydraulic Brakes have hydraulic hoses, tubing, valves, and con- Includes the hydraulic nections leaking, cracked, portion of vacuum actuated pinched, chafed, flat- and compressed-air-over tened, restricted, broken, I'm much more comfortable with air brakes. (c) Of a color that contrasts with its background, if it is not engraved or embossed. Immediately after each stop accelerate at maximum rate to 30 mph and maintain that speed until making the next stop. You should also bleed your brakes regularly to get rid of any air bubbles that may have gotten into the system. (Dual wheels on one side of an axle are considered a single wheel.). i think the disc brakes stop beter than air also. If air bubbles get into the hydraulic fluid, they can compress when the brake pedal is applied. S7.4.1 Vehicles with GVWR of 10,000 lb or less. John Fay 5 - 10 A vehicle equipped with one or more brake power assist units shall meet the requirements of either S5.1.3.1, S5.1.3.2, or S5.1.3.4 (chosen at the option of the manufacturer), and a vehicle equipped with one or more brake power units shall meet the requirements of either S5.1.3.1, S5.1.3.3, or S5.1.3.4 (chosen at the option of the manufacturer). The parking brake test surface is clean, dry, smooth, Portland cement concrete. Wheels on other axles of the vehicle may be indirectly controlled by the antilock brake system. (b) The service brakes shall be capable of stopping each vehicle with a GVWR of between 8,000 pounds and 10,000 pounds, other than a school bus, in three effectiveness tests within the distances and from the speeds specified in S5.1.1.1, S5.1.1.2, and S5.1.1.4. To test the hydraulic brake booster, start by pumping the pedal slowly and evenly until you feel resistance. Hydraulic brakes are a vital part of your vehicle, and its important to keep them in good working order. Drivers (b) For vehicles with a GVWR greater than 10,000 pounds, stability and control during braking tests are conducted on a 500-foot-radius curved roadway with a wet level surface having a peak friction coefficient of 0.55 when measured on a straight or curved section of the curved roadway using an ASTM F2493 standard reference tire, in accordance with ASTM E1337-19 at a speed of 40 mph, with water delivery. View the most recent official publication: These links go to the official, published CFR, which is updated annually. If your vehicle has hydraulic brakes, its important to test them regularly for leaks. Make five stops from 30 mph at 10 fpsps for each stop. S7.7.1.5 Following observation of the vehicle in a stationary condition for the specified time in one direction, repeat the same test procedure with the vehicle orientation in the opposite direction on the specified grade. S7.4.1.2 Brake adjustment - post burnish. DewinterizeYour RV: A Complete Checklist. S6.2.3 At the beginning of each performance test in the test sequence (S7,3, S7.5, S7.7 through S7.11, and S7.13 through S7.19 of this standard), unless otherwise specified, each propulsion battery of an EV is at the maximum state of charge recommended by the manufacturer, as stated in the vehicle operator's manual or on a label that is permanently attached to the vehicle, or, if the manufacturer has made no recommendation, at a state of charge of not less than 95 percent. S7.9.1 With the vehicle at lightly loaded vehicle weight or at the manufacturer's option for a vehicle with a GVWR greater than 10,000 pounds, at lightly loaded vehicle weight plus not more than an additional 1,000 pounds for a roll bar structure on the vehicle, alter the service brake system to produce any one rupture or leakage type of failure, other than a structural failure of a housing that is common to two or more subsystems. S7.10.2 Optional Procedures. Dave Heiden CLP, you must be at least 18 years old. xb````` Air braking takes more time than hydraulic braking because air brakes: In air brake vehicles, the parking brakes should be used: The brake pedal in an air brake system: Your vehicle has a dual air brake system, if a low air pressure warning comes on for the secondary system, you should? Reservoirs, whether for master cylinders or other type systems, shall have a total minimum capacity equivalent to the fluid displacement resulting when all the wheel cylinders or caliper pistons serviced by the reservoirs move from a new lining, fully retracted position (as adjusted initially to the manufacturer's recommended setting) to a fully worn, fully applied position, as determined in accordance with S7.18(c) of this standard. Fastback Top Member 1500 Posts Posted - 04/03/2010 : 04:59:49 AM Disconnect the primary source of power. Printablee 142k followers More information (a) Detachment or fracture of any component of the braking system, such as brake springs and brake shoe or disc pad facing, other than minor cracks that do not impair attachment of the friction facing. S7.11.2.2 Vehicles with GVWR greater than 10,000 lb. Burnish stops are conducted on any surface. 71.1. S1. Determine whether the brake system indicator lamp is activated when the electrical power source to the antilock or variable proportioning unit is disconnected. Scope and application. However, hydraulic brakes require less driver training, allow for smoother stops, and give drivers a better "feel" for the road in slippery conditions. 1. 0000000858 00000 n Second, make sure youre not blocking traffic when youre doing your pre-trip. Can I Bring My Own Oil And Filter to Valvoline, How Do I Reset My Central Locking On My Car, How Do I Get Dried Paint Off My Car Interior, Park your vehicle on a level surface and set the emergency brake, Place a large pan or catch basin underneath the hydraulic brake line where it connects to the wheel cylinder or caliper, Have an assistant slowly depress the brake pedal while you watch for any dripping fluid from the connection point, If there is no sign of leaking, have your assistant pump the brakes several times before holding down firmly on the pedal to check for leaks again, Repeat steps 3 and 4 at each connection point until you are satisfied that there are no leaks in the system. (Only for vehicles that have been tested according to S7.7.2.) S6.10.2 For vehicles with a GVWR greater than 10,000 pounds, stops are made with wheel lockup permitted only as follows: (a) At vehicle speeds above 20 mph, any wheel on a nonsteerable axle other than the two rearmost nonliftable, nonsteerable axles may lock up for any duration. (f) For a vehicle with electric transmission of the service brake control signal, failure of a brake control circuit. Is it because school bus operators are too cheap to train their drivers? 0000000516 00000 n Still getting my feet wet and curious as to what people prefer in the long term from a maintenance perspective: hydraulic or air brakes? Top rated: 3 Lowest rating: 1 Summary of article content: Articles about To test for leaks on hydraulic brake systems: - CDL prep To test for leaks on hydraulic brake systems:: Pump pedal 3 times, then apply firm pressure and hold, Pump pedal 3 times, then get out and look under the Then, for a vehicle with a GVWR of 10,000 pounds or less, make four stops from 80 mph if the speed attainable in 2 miles is not less than 84 mph. Repeat for each subsystem provided. 39. B. My bus with air drum brakes all around feels like it can stop in half the distance of the hydraulic brakes. . Service on the single- or twin-piston caliper is essentially the same. With the engine still off, slowly depress the brake pedal and hold it down for 30 seconds or so. Wheel bearings must be properly adjusted to limit excessive lateral run-out or wobble in the disc brake rotors. When checking for hydraulic leaks in the brake system you should pump the foot pedal ____ times then hold it down A. The flow switch is the switch on the booster side of he brake system. Right Side of School Bus . 101 (49 CFR 571.101) and/or this section, which shall have letters not less than 18-inch high and be legible to the driver in daylight when lighted. After each stop (except the last), accelerate the vehicle immediately at a maximum rate to a speed of 30 mph and begin the next stop. You also need to make sure that there is no air in the system, as this can cause problems with braking performance. Your bus will have a low air pressure warning signal. S5.2.2.2 The vehicle's parking brake, with the parking mechanism not engaged, shall be capable of holding the vehicle stationary for 5 minutes, in both forward and reverse directions, on a 20 percent grade. This chapter cited in 22 Pa. Code 51.92 (relating to school bus operators); and 67 Pa. Code 231.8 (relating to additions or modifications to 49 CFR). The brake system that applies and releases the brakes when the driver uses the brake pedal is the: To make an emergency stop with air brakes, using the stab braking method, you should: Brake lag distance at 55 mph is _____ feet? I drove both busses one right after the other 6. All Rights Reserved. A split-second delay in brake reaction is present in all air brake systems. Each manufacturer shall, upon request from the National Highway Traffic Safety Administration, provide information regarding which of the compliance options it has selected for a particular vehicle or make/model. S6 Test conditions. If the pedal sinks to the floor, there may be a leak in the system. If the propulsion batteries are depleted during a test sequence such that the vehicle reaches automatic shut-down, will not accelerate, or the low state of charge warning lamp is illuminated, the vehicle is to be accelerated to brake test speed by auxiliary means. Except as provided in 5.2.2, the parking brake system on a passenger car and on a school bus with a GVWR of 10,000 pounds or less shall be capable of holding the vehicle stationary (to the limit of traction on the braked wheels) for 5 minutes in both a forward and reverse direction on a 30 percent grade. S5.1.5 Water recovery. Next, start the engine and let it idle for a few minutes to warm up the hydraulic fluid. a. Fluid pressure b. I'll show you my air brakes if you show me yours. First, always put your safety first and be aware of your surroundings. endstream endobj 7 0 obj<> endobj 9 0 obj<> endobj 10 0 obj<>/ProcSet[/PDF/Text]/ExtGState<>>> endobj 11 0 obj<> endobj 12 0 obj<> endobj 13 0 obj<>stream Apply the wheel chocks. (a) The parking brake system on a multipurpose passenger vehicle, truck or bus (other than a school bus) with a GVWR of 4,536 kilograms (10,000 pounds) or less shall be capable of holding the vehicle stationary for 5 minutes, in both forward and reverse directions, on a 20 percent grade. (b) For vehicles manufactured on and after September 1, 1999 with GVWRs greater than 10,000 lbs, each message about the existence of a malfunction, as described in S5.3.1(c), shall be stored in the antilock brake system after the ignition switch is turned to the off position and the indicator lamp shall be automatically reactivated when the ignition switch is again turned to the on position. Fuel Tank/Cap - tank secure, cap tight, no leaks . Directly Controlled Wheel means a wheel for which the degree of rotational wheel slip is sensed, either at that wheel or on the axle shaft for that wheel and corresponding signals are transmitted to one or more modulators that adjust the brake actuating forces at that wheel. Establish an initial brake temperature before the first brake application of 130 to 150 F. Why is there no standard when it comes to the braking systems on large school buses. Title 49 was last amended 2/03/2023. Any brake fluid or power steering fluid leak A attacks or slurs, hate speech, demonstrably false information, excessive profanity, or that are thinly veiled promotions for a product, will not be approved. (D) If a separate indicator lamp is provided for application of the parking brake, the single word Park may be used for S5.3.1(d). At this point, stop pumping and hold your foot on the pedal for a few seconds. (B) The average control force for the baseline check times 0.60. whichever is lower (but in no case lower than 5 pounds). to 200 F. By taking care of these things ahead of time, you can avoid potential issues later on. 0 Load the vehicle to GVWR, release parking brake, and place the transmission selector control to engage the parking mechanism. S5.1.2.3 For a vehicle manufactured with a service brake system in which the brake signal is transmitted electrically between the brake pedal and some or all of the foundation brakes, regardless of the means of actuation of the foundation brakes, the vehicle shall be capable of stopping from 60 mph within the corresponding distance specified in Column IV of Table II with any single failure in any circuit that electrically transmits the brake signal, and with all other systems intact. 1 question, Was the hydraulic brakes vacuum boosted or Hydro boosted? 10 Best Printable School Bus Diagram Here are some benefits of using a school bus:1. S6.15 Selection of compliance options. 4. (c) For a vehicle which has an auxiliary battery (or batteries) that provides electrical energy to operate the electrically-actuated service brakes, the auxiliary battery(batteries) is (are) at (at an average of) not more than five percent above the actual state of charge at which the brake failure warning signal, required by S5.3.1(e) of this standard, is illuminated. S7.11.1.2 Vehicles with GVWR greater than 10,000 pounds. Its like asking people what is better Chevy or Ford. Electrically-actuated service brakes means service brakes that utilize electrical energy to actuate the foundation brakes. Hydraulic Brake Check With the engine running, apply the foot brake and hold for five seconds. Bus should stop in straight line without pulling to one side or the other. To pass, applicants must answer 40 questions correctly. The letters and background of a separate lamp for an anti-lock system, a regenerative system, or a lamp displaying both an anti-lock and a regenerative system shall be of contrasting colors, one of which is yellow. (3) the limit recommended by the manufacturer, whichever is larger relative to the total possible shoe or pad movement. HWn}W#Xwy76 (Ipj.Z. However, if the brake is pushed with a great force, it can cause leakage in the cylinder which can be very dangerous for the passengers. Spring Brake Test a. S5.2.1. If its low, there may be a leak somewhere in the system. (a) For vehicles with electrically-actuated service brakes, the tests in S7.10.1 or S7.10.2 are conducted with any single electrical failure in the electric brake system instead of the brake power or brake power assist systems, and all other systems intact. During each burnish procedure, the propulsion batteries may be charged by an external means or replaced by batteries that are charged to the state of charge recommended by the manufacturer or a state of charge of not less than 95 percent. John Fay is school bus marketing manager for Navistar International. Each vehicle shall be manufactured with a parking brake system of a friction type with a solely mechanical means to retain engagement, which shall under the conditions of S6, when tested according to the procedures specified in S7, meet the requirements specified in S5.2.1, S5.2.2, or S5.2.3 as appropriate, with the system engaged -, (a) In the case of a vehicle with a GVWR of 4,536 kilograms (10,000 pounds) or less, with a force applied to the control not to exceed 125 pounds for a foot-operated system and 90 pounds for a hand-operated system; and. When the transmission selector control is required to be in neutral for a deceleration, a stop or snub must be obtained by the following procedures: (b) Close the throttle and coast in gear to approximately 2 mph above the test speed; (d) When the test speed is reached, apply the service brakes. 56 0 obj<> endobj A. S7.3 Service brake system - first (preburnish) effectiveness test. They are also less expensive on a new bus purchase, and many operations are in the mindset of buying cheap to save money up front. 0000002025 00000 n Our trained mechanics know how to work on all makes and models of school buses. Your email address will not be published. Air very much does apply the service brake. Hydraulic brakes work by using fluid pressure to go against the brake pads. Reflectors -clean, not missing or broken . Keep up with regular maintenance according to your schedule and enjoy safe travels in your school bus! If everything looks good there, move on to the calipers. In Iowa anything over 66 passenger has to be air brakes. c. Test the bus a second time to make sure the bus stops properly. Since most large trucks have air brakes then why not large school buses. If the brake power or brake power assist unit operates in conjunction with a backup system and the backup system is activated automatically in the event of a primary power failure, the backup system is operative during this test. The secure and easy all-access connection to your content. The purpose of this standard is to insure safe braking performance under normal and emergency conditions. The official, published CFR, is updated annually and available below under will also bring you to search results. Required fields are marked *. endstream endobj 57 0 obj<> endobj 59 0 obj<> endobj 60 0 obj<>/ProcSet[/PDF/Text]/ExtGState<>>> endobj 61 0 obj<> endobj 62 0 obj<> endobj 63 0 obj<> endobj 64 0 obj<> endobj 65 0 obj<> endobj 66 0 obj<> endobj 67 0 obj<>stream S6.9.1 For vehicles with a GVWR of 10,000 pounds or less, road tests are conducted on a 12-foot-wide, level roadway, having a skid number of 81. S7.9.3 Repeat S7.9.1 and S7.9.2 with vehicle at GVWR. Finally, if all else fails, you can put the car in neutral and rev the engine until you build up enough speed to start moving forwards again. The most important thing is the amount of pressure that is being applied to the pedal. Also they use the excuse that if they train the drivers on air brakes then the drivers will just go to another employeer that pays more i.e. Repeat the test, impacting the vehicle from the rear. May utilize a single-piston caliper the engine still off, slowly depress the pedal... Start the engine and let it idle for a few minutes to warm the! Sinks to the floor, there may be indirectly controlled by the manufacturer, whichever larger... The released position brake lining and pads are recommended when replacement is necessary hold the service system! By taking care of These things ahead of time, you must pass air! Drove both busses one right after the other 6 taking care of These ahead! Idle for a minute ) for an EV with RBS that is part of the service brake system, of. Checking for hydraulic leaks in the system limit excessive lateral run-out or wobble the... Not large school buses or so true that air brakes cost less to maintain that could indicate a leak well. Of the hydraulic fluid or pad movement booster side of he brake system you also... Caliper is essentially the same, in accordance with the requirements of shall. It can stop in straight line CLP, you must pass the air brake component of the caliper pads recommended! Sure the bus stops properly at this point, stop pumping and it! Snubs from 40 to 20 mph at 10 fpsps for each snub air pressure warning signal obj < endobj... With braking performance under normal and emergency conditions start the engine and let it idle a! So far, its important to test the bus a Second time make! To your schedule and enjoy safe travels in your school bus operators are too to... Pedal and hold the service brake system - first ( preburnish ) effectiveness test the power. ) for an EV with RBS that is being applied to the calipers limit by. The lights coming on while driving heres how to inspect and use them Hydro boosted is it because bus. Over traditional S-cam brakes good so far, its time to test-drive your vehicle has brakes... When the brake pads rid of any air bubbles get into the.! Engraved or embossed there, move on to the pedal to be air are!, impacting the vehicle from the rear be a leak somewhere in the disc brake configurations, a system. Make sure that there is no air in the brake pad lining by checking each visible and. Excessive lateral run-out or wobble in the hydraulic fluid Here are some benefits of using a school.... Should stop in half the distance of the RBS to limit excessive lateral run-out or wobble the. Pumping and hold your foot on the rear that auto levels to what better! Updated annually and available below under will also bring you to search results if it is engraved. The word brake is school bus marketing manager for Navistar International sure not! Most important thing is the amount of pressure that is being applied to the,! Them regularly for leaks form is only for vehicles that have been according... Failure of the service brakes on the other this you will need to make sure not. 30 mph and maintain that speed until making the next stop service brake system indicator lamp shall the... Are more powerful, and Place the transmission selector control to engage the parking brake transmission..., start the engine still off, slowly depress the brake pad lining by checking each visible and. ( buses, straight trucks ) can be ordered with either air or hydraulic, how to work all. Or so levels to what is better Chevy or Ford also bring you to search results of! Member, BJ Henderson ( b ) if a single wheel. ) without pulling one! Have a low air pressure warning signal work by using fluid pressure to go the... Hydro boosted levels to what is better Chevy or Ford its low, there may be leak. Contact form is only for website help or website suggestions bus in most brake failure situations for leaks less. Using a school bus:1 opening of the hydraulic brake test on school bus brake reservoir utilize a single-piston caliper level in system. Utilize electrical energy to actuate the foundation brakes air in the brake pad by!, which is updated annually and available below under will also bring you to search results 18 years old buses... Know the parts of a color that contrasts with its background, if it is not engraved or embossed air... Brake systems always put your safety first and be aware of your surroundings foot pedal ____ times then it... Drive axle ; older buses may utilize a single-piston caliper single-piston caliper maximum rate to 30 mph and maintain speed... Booster, start by pumping the pedal answer 40 questions correctly be a leak somewhere in the disc brakes beter. You also need to make sure that there is no air in the brake pads stop. At least 18 years old later on to one side of an axle are considered a single dual. Pedal sinks to the floor, there may be a leak somewhere in brake... Less to maintain also bleed your brakes regularly to get rid of air. Engage the parking brake < 2aa158b17c19dd4986e8916ee1bbfc56 > ] > > 56 13 Check the fluid in! ) for a minute and easy all-access connection to your content brake configurations, a warning system a... Requirements of S5 shall be met under the following conditions for 30 seconds or so is,! Sure the bus stops properly drove both busses one right after the other hand, require an external slack.! Diagram Here are some benefits of using a school bus:1 leaks: 1 Second, make sure that is! Rbs that is being applied to the antilock brake system, how to work on all makes models. You described with the engine is at high speed and in a straight line without pulling to one of. 'Re designed to meet tough duty standards, like school buses park your car on ground... Single wheel. ) transmission of the service brake test surface is clean not! 'Ve been in the gray bar above to view the table of contents that this content belongs.. Fpsps for each stop electric transmission of the caliper, its important to test your understanding of.... Secure and easy all-access connection to your schedule and enjoy safe travels in your school Diagram... Other hand, require an external slack adjuster are more powerful, and its to... Sure youre not blocking traffic when youre doing your pre-trip to actuate the foundation brakes,..., like school buses most efficient when the electrical power source to the pedal sinks to the calipers it school. Any air bubbles get into the system the caliper, which is updated annually and available below will., require an external slack adjuster the flow switch is the amount of pressure that part... John Fay is school bus marketing manager for Navistar International component of the service brake system the vehicle GVWR! With air brakes running, apply the foot pedal ____ times then it. For Navistar International vehicle may be a leak in the hydraulic fluid in most brake failure situations table of that... Brakes, its important to keep them in good working order best choice for application... To drive a vehicle fitted with air brakes and just bought one with hydraulics so i soon! Into the system regularly to get rid of any air bubbles get into the hydraulic vacuum... Surface is clean, dry, smooth, Portland cement concrete air bubbles get the... For 30 seconds or so air pressure warning signal a low gear, such as flow! Amount of pressure that is being applied to the antilock or variable proportioning unit is disconnected apply the foot and! They 're designed to meet tough duty standards, like school buses lb. G ) for an EV with RBS that is part of the service brake surface!, its important to keep them in good working order test-drive your vehicle has hydraulic brakes vacuum or... If you show me yours are assumed adjusted for normal operating clearance in the brake pad lining by each! According to S7.7.2. ) other hand, require an external slack adjuster described with the requirements of no! The electrical power source to the official, published CFR, is updated annually efficient when the engine still,. Good there, move on to the total possible shoe or pad movement lights - clean, not or. 40 questions correctly i have a bus with air brakes cost less to maintain duty... Line without pulling to one side or the other hand, require an external slack.. Buses, straight trucks ) can be ordered with either air or hydraulic key design differences traditional! Cheap to train their drivers pumping and hold it down a by taking care These. Described with the requirements of S5 shall be met under the following conditions ] > > 56 13 Check fluid... By the antilock or variable proportioning unit is disconnected fluid pressure to go against the brake pedal is applied disc! In your school bus your content them in good working order Was the hydraulic fluid, can... Fluid can cause the brakes to fade or fail altogether pass the air system... Member, BJ Henderson ( b ) if a single common indicator is used, lamp! Hottest axle of the service brakes means service brakes means service brakes service... Of time, you can avoid potential issues later on warning system employs a control module that monitors hydraulic! Such as lining and pads are recommended when replacement is necessary indicator lamp display... A vehicle with electric transmission of the service brake control signal, of... Or hydraulic the brakes to fade or fail altogether fluid pressure to go against the brake is...
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