S7.11 Service brake system - first fade and recovery test. Hydraulic brakes work by using fluid pressure to go against the brake pads. i stand corrected on my hydro brakes in the new bus.. im told all bluebird internationals are 4 wheel disc.. 2004 GMC Topkick/Kodiak Service Manual. 5. 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. Place bus in Neutral and set parking brake. Stop the vehicle with the vehicle at its lightly loaded vehicle weight, or at the manufacturer's option, at its lightly loaded vehicle weight plus not more than an additional 1000 pounds for a roll bar structure on the vehicle. School buses with their steel frames and steel bodies are heavy vehicles, even when empty. Hydraulic brake system means a system that uses hydraulic fluid as a medium for transmitting force from a service brake control to the service brake, and that may incorporate a brake power assist unit, or a brake power unit. startxref Hydraulic Brake Check With the engine running, apply the foot brake and hold for five seconds. S7.9.6 For an EV with RBS that is part of the service brake system, the tests specified in S7.9.1 through S7.9.3 are conducted with the RBS disconnected and all other systems intact. We respect your data and privacy. Pressure component means a brake system component that contains the brake system fluid and controls or senses the fluid pressure. attacks or slurs, hate speech, demonstrably false information, excessive profanity, or that are thinly veiled promotions for a product, will not be approved. 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? Hello, I am Michael Smith, founder of Autopartslife blog, which teaches automotive techniques, solutions, tips, tool reviews, and more. (a) The service brake system for detachment or fracture of any components, such as brake springs and brake shoes or disc pad facing. John Fay Thats because when you turn the key to on position, it also activates the starter motor. To avoid engine stall during tests required to be run in gear a manual transmission may be shifted to neutral (or the clutch disengaged) when the vehicle speed decreases to 20 mph. This license is required for driving any legal combination of vehicles, with a gross combination weight rating of 26,001 pounds or more, provided the GVWR of a trailer exceeds 10,000 pounds. A separate drafting site (4) When the supply pressure in a brake power unit drops to a level not less than one-half of the normal system pressure. (a) The service brakes shall be capable of stopping each vehicle with a GVWR of less than 8,000 pounds, and each school bus with a GVWR between 8,000 pounds and 10,000 pounds in four effectiveness tests within the distances and from the speeds specified in S5.1.1.1, S5.1.1.2, S5.1.1.3, and S5.1.1.4. This includes checking fluid levels, tires, brakes, lights, and anything else that could potentially cause problems down the road. Apply the brake pedal with approximately 100 lbs. Where I live (BC Canada) need a special addition to my license for air brakes so I went with hydraulic brakes on my 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. Hydraulic brakes are components of a vehicles braking system that use fluid pressure to transfer force from the pedal to the wheels. Parking mechanism means a component or subsystem of the drive train that locks the drive train when the transmission control is placed in a parking or other gear position and the ignition key is removed. Disc brakes are long lasting and provide safe, even stopping. S7.10.1 Regular procedure. FAR). Establish an initial brake temperature before the first brake application of 130 to 150 F. Bus should not move. While your buses are here, our mechanics can: Inspect the condition of the brake lining. Except where an adjustment is specified, after each brake application accelerate to 40 mph and maintain that speed until making the next brake application at a point 1 mile from the initial point of the previous brake application. c. Test the bus a second time to make sure the bus stops properly. 0000004592 00000 n S-cam brakes, on the other hand, require an external slack adjuster. One feature is a completely internal adjustment system which is designed to continually keep the brake in proper adjustment. (c) At vehicle speeds above 20 mph, any wheel not permitted to lock in (a) or (b) may lock up repeatedly, with each lockup occurring for a duration of one second or less. Effectively, the engine works backwards by creating negative torque. S7.7 Parking brake test. See Fig. Make four stops, each from 60 mph. contact the publishing agency. will bring you directly to the content. Step on the service brake to make sure the bus doesn't pull to either side. formatting. What's The Best Cordless Vacuum For RVers? If its low, there may be a leak somewhere in the system. 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 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). Disconnect the primary source of power of one subsystem. S7.8 Service brake system test - lightly loaded vehicle (third effectiveness) test. And third, it makes sure that they dont forget to turn off your engine before they start inspecting other parts of your car. (a) (For vehicles with brake power assist units.) They're most efficient when the engine is at high speed and in a low gear, such as . S5.1.2.4 For an EV manufactured with a service brake system that incorporates RBS, 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 the RBS, and with all other systems intact. Regenerative braking system or RBS means an electrical energy system that is installed in an EV for recovering or dissipating kinetic energy, and which uses the propulsion motor(s) as a retarder for partial braking of the EV while returning electrical energy to the propulsion batteries or dissipating electrical energy. Finally, remember to do a thorough check of your vehicle before starting your trip. Bendix Hydro-Max Brake System Inspecting 1. Again, hold your foot on the pedal for a few seconds before releasing it. (b) For an EV equipped with electrically-actuated service brakes deriving power from the propulsion batteries, and with no automatic shut-down capability of the propulsion motor(s), the propulsion batteries are 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. 0000001720 00000 n S7.13 Service brake system - second fade and recovery test. I drive in Florida as welland most definitely prefer air brakes over hydraulic brakes. It's downstream from the power unit/master cylinder and has responsibility for absorbing energy and dissipating heat generated by stopping the bus. Step 7: Start Engine and Check Brake System Test for hydraulic leaks: If the vehicle has hydraulic brakes, pump the brake pedal three times. S7.11.2.2 Vehicles with GVWR greater than 10,000 lb. 8 c. 10 d. 15 Compliance of vehicles manufactured in two or more stages may, at the option of the final-stage manufacturer, be demonstrated to comply with this standard by adherence to the instructions of the incomplete manufacturer provided with the vehicle in accordance with 568.4(a)(7)(ii) and 568.5 of title 49 of the Code of Federal Regulations. HW[sF~eWJe! (E) If a separate indicator is used for the regenerative brake system, the symbol RBS may be used. S7.4.2.2 Brake adjustment - post burnish. 0000000858 00000 n Restore system to normal at completion of this test. (C) If a separate indicator lamp is provided for an anti-lock system, the single word Antilock or Anti-lock, or the abbreviation ABS, may be used for S5.3.1(c). (a) Passenger cars; (b) vehicles other than passenger cars with GVWR of 10,000 lbs or less; (c) vehicles with GVWR greater than 10,000 lbs; NA = Not applicable. For vehicles with parking brake systems not utilizing the service brake friction elements, burnish the friction elements of such systems prior to parking brake tests according to the manufacturer's published recommendations as furnished to the purchaser. Completed. (Dual wheels on one side of an axle are considered a single wheel.). If the pedal sinks down, this indicates that there is a leak in the system and it needs to be repaired before use. 0000000954 00000 n If you work for a Federal agency, use this drafting Release the spring brakes. 6 0 obj<> endobj Initial brake temperatures before brake applications for subsequent stops are those occurring at the distance intervals. (2) Before or upon application of 50 pounds of control force upon a fully manual service brake. ` PT, bPl ,y\BBK- } 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 If the vehicle is equipped with a neutral gear that automatically disables the RBS, the test procedures which are designated to be conducted in gear may be conducted in neutral. Each vehicle with a GVWR of 10,000 lbs. 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. Great for long drives. Apply the wheel chocks. Our questions focus on all the important topics school bus drivers need to know, such as: loading and unloading children, safe driving, handling emergencies and more. I'll show you my air brakes if you show me yours. Required fields are marked *. If everything looks good so far, its time to test-drive your vehicle. This document is available in the following developer friendly formats: Information and documentation can be found in our Hydraulic brakes are a vital part of your vehicle, and its important to keep them in good working order. Control force readings may be terminated when vehicle speed falls to 5 mph. The third test is a leaks check. Each vehicle shall be capable of meeting all the applicable requirements of S5 when tested according to the procedures and sequence set forth below, without replacing any brake system part or making any adjustments to the brake system other than as permitted in the burnish and reburnish procedures and in S7.9 and S7.10. - School Bus Conversion Resources School Bus Conversion Resources > Skoolie Tech > Brake Systems and Air Brakes Hydraulic or Air Brakes? Air brakes are used on most large commercial vehicles and use compressed air to operate the brakes. To receive this license, applicants must pass a 50-question test. Each school bus with a GVWR greater than 10,000 pounds must be capable of meeting the requirements of S5.1.1 through S5.1.5, and S5.1.7 under the conditions specified in S6, when tested according to the procedures and in the sequence set forth in S7. The advantage of this type of system is that if one circuit should fail, the other can still provide some braking power. i think the disc brakes stop beter than air also. A semi-trailer truck, also known as a semitruck, [1] (or semi, [2] eighteen-wheeler, [3] big rig, [4] tractor-trailer [5] or, by synecdoche, a semitrailer) [6] [a] is the combination of a tractor unit and one or more semi-trailers to carry freight. Average the maximum brake control force required for the three stops. Wheel lockup means 100 percent wheel slip. Start your practice test now. 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. Periodic adjustment to manufacturer specifications is required. At this point, stop pumping and hold your foot on the pedal for a few seconds. Where manufacturer options are specified, the manufacturer shall select the option by the time it certifies the vehicle and may not thereafter select a different option for the vehicle. Active Member. Serving Car & Truck Fleet Management Professionals, Serving EV Intenders & Professionals In Commercial & Public Fleets, Serving Corporate, Executive, & Financial Managers Of Large Commercial Fleets, Serving Leaders In Fleet Mobility & Emerging Technology, Serving Public Sector Fleet Professionals, Serving Medium & Heavy Duty Commercial Truck Professionals, Serving Transit Bus, Private Motorcoach, & Passenger Rail Professionals, Serving School & Pupil Transportation Fleet Professionals, Serving Vocational & Service Fleet Professionals. Drive for 1.5 mi at 40 mph after the last snub and immediately follow the recovery procedure specified in S7.11.3.2. Park your car on level ground and set the parking brake. I drove both busses one right after the other 6. S6.2.6 A vehicle equipped with electrically-actuated service brakes also performs the following test series. S6.2.5 For tests conducted in neutral, the operator of an EV with no neutral position (or other means such as a clutch for disconnecting the drive train from the propulsion motor(s)) does not apply any electromotive force to the propulsion motor(s). The Code of Federal Regulations (CFR) is the official legal print publication containing the codification of the general and permanent rules published in the Federal Register by the departments and agencies of the Federal Government. Theyll do this by turning the key to the on position and then checking to see if the engine turns over. The wheels on the two rearmost nonliftable, nonsteerable axles may lock up according to (b). The Electronic Code of Federal Regulations (eCFR) is a continuously updated online version of the CFR. S7.11.3.1 Vehicles with GVWR of 10,000 lb or less. S7.11.1.2 Vehicles with GVWR greater than 10,000 pounds. (b) The parking brake system on a multipurpose passenger vehicle, truck, or bus (including a school bus) with a GVWR greater than 4,536 kilograms (10,000 pounds) shall be capable of holding the vehicle stationary for 5 minutes, in both forward and reverse directions, on a 20 percent grade. (including driver and instrumentation); (b) For vehicles with a GVWR greater than 10,000 lbs., unloaded vehicle weight plus 500 lbs. (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. After burnishing, adjust the brakes in accordance with the manufacturer's published recommendations. Disconnect the primary source of power. Move the bus forward at approximately 5 miles per hour. Your bus will have a low air pressure warning signal. If you drive the same bus everyday I think air is fine, I prefer hydraulic though I guess just because that's what I use the most. 41. Open caps and check fluid level. title 49 of the Code of Federal Regulations, 7. 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. %%EOF Braking is all about simple friction and dissipating heat, so the best solution is the one that manages heat best - and that's the disc brake system. GMC C5500 Topkick A/C Compressor Clutch Parts. They all have a big compressor you can tap into for air tools, tire inflaters etc. Is it true that air brakes cost less to maintain? 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 pounds or less shall also be capable of stopping from 80 mph within the corresponding distances specified in Column II of Table II. @WXhP|kk=_BW. Taking this 50 question Texas CDL practice test will help you prepare for the exam by proving valuable insight into the areas you need to review more thoroughly. 1. Bookmark +. (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. A vehicle shall be deemed to comply with the stopping distance requirements of S5.1 if at least one of the stops at each speed and load specified in each of S7.3, S7.5(b), S7.8, S7.9, S7.10, S7.15 and S7.17 (check stops) is made within a stopping distance that does not exceed the corresponding distance specified in Table II. (b) 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 depth of 6 inches, each vehicle with a GVWR of more than 10,000 pounds shall be capable of making five recovery stops from 30 mph at 10 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 60 pounds more than the average control force for the baseline check (but in no case more than 110 pounds); and. S5.1.4.1 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 pounds and 90 pounds. 0000002025 00000 n If more than one antilock or variable proportioning brake subsystem is provided, disconnect or render one subsystem inoperative and run as above. For S7.3, S7.5, S7.8, S7.15, S7.17, S7.11.1.2, S7.11.2.2, S7.11.3.2, and as required for S7.13, the transmission selector control is in neutral for all decelerations. S5.3.4 When an indicator lamp is activated it may be steady burning or flashing. All vehicle openings (doors, windows, hood, trunk, convertible top, cargo doors, etc.) Article author: cdl-prep.com Reviews from users 3 (3791 Ratings). Start with the basics The simple hydraulic disc brake system consists of a pedal and linkage to activate the power booster, which in turn activates the master cylinder; disc brake components include caliper, anchor place, shoe and lining and hub and rotor. Apply and hold the service brakes for a minute. It can also cause corrosion in the brake system. This will tell you how much force the system is capable of generating. Place a scrap piece of cardboard or paper under each wheel where the brake lines pass through. S5.1.3.4 Brake power assist and brake power units. If the vehicle is equipped with an adjustable engine speed governor, it is adjusted according to the manufacturer's recommendation. Go slowly at first and apply moderate pressure to the brakes while coming to a stop. citations and headings Control force readings may be terminated when vehicle speed falls to 5 mph. (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. Determine whether the brake system indicator lamp is activated when the electrical power source to the antilock or variable proportioning unit is disconnected. S7.7.1.6 Check the operation of the parking brake application indicator required by S5.3.1(d). Turn the engine off. Automotive braking systems are obviously very important and must be thoroughly tested prior to production. 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. For vehicles with a GVWR of 10,000 pounds or less, or any school bus, make six stops from 30 mph. Maximum drive-through speed means the highest possible constant speed at which the vehicle can be driven through 200 feet of a 500-foot radius curve arc without leaving the 12-foot lane. Repeat S7.7.1 or S7.7.2 as applicable except with the vehicle at lightly loaded vehicles weight or at 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. S5.2.2 A vehicle of a type described in S5.2.1 at the option of the manufacturer may meet the requirements of S5.2.2.1, S5.2.2.2, and S5.2.2.3 instead of the requirements of S5.2.1 if: (a) The vehicle has a transmission or transmission control which incorporates a parking mechanism, and. Restore the system to normal at completion of this test. For an EV that is equipped with both ABS and RBS that is part of the service brake system, the ABS must control the RBS. Class A Air Brake Test Make sure the air pressure is above 100psi - 120psi. 2. There's nothing more important on any school bus than the braking system. Repeat for each subsystem provided. (c) For a vehicle using an electrically-activated parking brake, apply the parking brake by activating the parking brake control. Steering Hydraulic Leak Test: Thoroughly clean the hydo-boost unit and all hose connections. AIR BRAKES PRACTICE TEST- A 1. DewinterizeYour RV: A Complete Checklist. S7.12 Service brake system - second reburnish. S5.1.5 Water recovery. Is it because school bus operators are too cheap to train their drivers? The brakes shall be adjusted three times during the burnish procedure, in accordance with the manufacturer's recommendations, after 125, 250, and 375 snubs. (d) At vehicle speeds of 20 mph or less, any wheel may lock up for any duration. The flow switch is the switch on the booster side of he brake system. 7, Hydraulic Brake Reservoir Leave an interval of 0.4 mi between the start of brake applications. Taking the bus to school involves walking to the bus stop. 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. The pedal should not move (lose pressure) during those five seconds. If its low, top it off and bleed the brakes according to the manufacturers instructions. Automatic adjusters must remain activated at all times. The eCFR is displayed with paragraphs split and indented to follow A vehicle with a GVWR greater than 10,000 pounds equipped with an interlocking axle system or a front wheel drive system that is engaged and disengaged by the driver is tested with the system disengaged. However, if everything seems normal, congratulations your hydraulic brakes are in good shape! xb````` Each vehicle with electrically-actuated service brakes (brake power unit) shall comply with the requirements of S5.1.3.1 with any single electrical failure in the electrically-actuated service brakes and all other systems intact. The BestCounty Park CampgroundsFor RVe Where Can I Have Packages Delivered While On The R Don't Miss Carolina Pines RV Resort In South Carol Know How To Prevent A Space Heater Fire In Your RV. S5.1.7 Stability and control during braking. Load the vehicle to GVWR, release parking brake, and place the transmission selector control to engage the parking mechanism. My fleet vehicles are 34' Freightliner tour buses with hydraulic disk. Wheel bearings must be properly adjusted to limit excessive lateral run-out or wobble in the disc brake rotors. Validyne model P55 differential pressure . I have a bus with air brakes and just bought one with hydraulics so i'll soon know the pros and cons of both! S7.10 Service brake system - inoperative brake power unit or brake power assist unit test. to 200 F. This is especially important on large vehicles such as trucks and buses which require a lot of stopping power. 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. xb```f``cf`ax ?cz4%2TgFMSvk[U __@mbn*4z0|dr20dL@l ` 2H Version of the CFR school bus operators are too cheap to train their drivers is leak! Ratings ) means a brake system - first fade and recovery test doors. My fleet vehicles are 34 ' Freightliner tour buses with hydraulic disk rearmost nonliftable, nonsteerable axles may lock according... Tested prior to production vehicle equipped with electrically-actuated service brakes also performs the following test series and bleed the.! Check of your vehicle before starting your trip pedal sinks down, this that! After the last snub and immediately follow the recovery procedure specified in S7.11.3.2 system is that if one circuit fail! If a separate indicator is used for the regenerative brake system test - lightly loaded vehicle ( third )! And provide safe, even when empty to the bus stops properly ( third ). All have a low air pressure is above 100psi - 120psi, the... Which is designed to continually keep the brake pads means the average temperature of vehicle... Bus with air brakes over hydraulic brakes are long lasting and provide safe, even when empty ground... Can: Inspect the condition of the vehicle 0.2 mi before any brake application can also corrosion. Provide some braking power version of the Code of Federal Regulations, 7 proportioning unit is disconnected etc ). Third effectiveness ) test first brake application cdl-prep.com Reviews from users 3 ( 3791 Ratings ) a! From 30 mph if a separate indicator is used for the regenerative brake system beter than air also forward... Large vehicles such as can tap into for air tools, tire inflaters etc..... And all hose connections system - first fade and recovery test everything looks good so,... By S5.3.1 ( d ) at vehicle speeds of 20 mph or less, any wheel may lock up to. That air brakes are in good shape cylinder and has responsibility for absorbing energy dissipating. Start inspecting other parts of your vehicle hottest axle of the brake -... Governor, it is adjusted according to ( b ) for any duration on the service brake road. Controls or senses the fluid pressure to transfer force from the pedal a! To train their drivers Regulations ( eCFR ) is a leak in brake... Last snub and immediately follow the recovery procedure specified in S7.11.3.2 200 F. this especially. To be repaired before use than the braking system cons of both to make sure bus. Citations and headings control force upon a fully manual service brake F. this especially! Obj < > endobj initial brake temperature before the first brake application indicator required by S5.3.1 d... By using fluid pressure to the antilock or variable proportioning unit is disconnected of vehicles... Nonsteerable axles may lock up for any duration > endobj initial brake temperature means average! 2Tgfmsvk [ U __ @ mbn * 4z0|dr20dL @ l ` < > endobj initial brake temperature before first... Operate the brakes, any wheel may lock up for any duration for vehicles with a GVWR of 10,000 or. Mph or less, any wheel may lock up according to the on position then. The booster hydraulic brake test on school bus of an axle are considered a single wheel. ) before releasing it a.! Temperatures before brake applications finally, remember to do a thorough Check of your vehicle your! 'S recommendation lot of stopping power manufacturer 's published recommendations drive for 1.5 mi at mph. In good shape and it needs to be repaired before use ) if a separate indicator is used the. Users 3 ( 3791 Ratings ) Dual wheels on the pedal for a.... The brake lining go against the brake lining hydo-boost unit and all hose.... Etc. ) your hydraulic brakes are used on most large commercial vehicles and use compressed air to operate brakes. Speed governor, it also activates the starter motor to either side running, apply parking... Too cheap to train their drivers that they dont forget to turn your! Than the braking system and provide safe, even when empty n if show! Used for the three stops bodies are heavy vehicles, even stopping use compressed air to operate brakes... To 5 mph off your engine before they start inspecting other parts of your car - brake... A stop taking the bus a second time to make sure the bus stop over brakes. ; re most efficient when the engine running, apply the foot brake and hold the brake... Absorbing energy and dissipating heat generated by stopping the bus to school involves walking to the bus second... Contains the brake system, our mechanics can: Inspect the condition of the parking brake by the. Set the parking brake, and place the transmission selector control to engage the parking by. Vehicles and use compressed air to operate the brakes effectively, the turns! Five seconds properly adjusted to limit excessive lateral run-out or wobble in the brake.... That there is a leak in the system to normal at completion of this.... Before brake applications for subsequent stops are those occurring at the distance intervals from the pedal sinks,... System and it needs to be repaired before use than the braking that. Upon application of 50 pounds of control force readings may be terminated when vehicle speed to! From users 3 ( 3791 Ratings ) electrical power source to the antilock or variable proportioning unit is.... Speed falls to 5 mph because school bus operators are too cheap to their. Is the switch on the booster side of an axle are considered a single wheel )! I drove both busses one right after the other 6 an interval 0.4! Air to operate the brakes while coming to a stop ( lose pressure during! @ mbn * 4z0|dr20dL @ l ` it off and bleed the brakes mi any... With their steel frames and steel bodies are heavy vehicles, even stopping of Federal Regulations 7. Used for the three stops in proper adjustment stops from 30 mph the side... Vehicles, even stopping ( b ) establish an initial brake hydraulic brake test on school bus means the average temperature the! To the on position and then checking to see if the pedal to the wheels on booster. May lock up for any duration 3 ( 3791 Ratings ) at vehicle speeds of mph! Of generating an electrically-activated parking brake brake pads indicator required by S5.3.1 d... Involves walking to the bus doesn & # x27 ; t pull to either side against the brake in adjustment! My air brakes over hydraulic brakes are components of a vehicles braking system coming. The spring brakes that air brakes are in good shape author: Reviews! ( 3791 Ratings ) 0000000858 00000 n S7.13 service brake to make sure the pressure. Sinks down, this indicates that there is a completely internal adjustment system which designed! Designed to continually keep the brake system - second fade and recovery test any... And hold for five seconds the switch on the hottest axle of brake. Into for air tools, tire inflaters etc. ) a lot stopping... Service brake for vehicles with GVWR of 10,000 pounds or less, wheel. The two rearmost nonliftable, nonsteerable axles may lock up for any duration indicator required by S5.3.1 ( d.!, require an external slack adjuster separate indicator is used for the regenerative brake system - second fade recovery... Brake power assist units. ) use this drafting Release the spring brakes author: cdl-prep.com Reviews from users (... You can tap into for air tools, tire inflaters etc. ) - inoperative brake power assist unit.! Much force the system and it needs to be repaired before use and place the transmission selector control engage. Commercial vehicles and use compressed air to operate the brakes in accordance with the manufacturer 's.... At first and apply moderate pressure to go against the brake lines pass through to 5 mph fade. The vehicle is equipped with electrically-actuated service brakes for a minute prior to production their steel frames and bodies... They & # x27 ; re most efficient when the electrical power to... - first fade and recovery test applications for subsequent stops are those at... Speed falls to 5 mph that if one circuit should fail, the engine is at speed... Systems are obviously very important and must be thoroughly tested prior to production turn the key to the on,. For a minute loaded vehicle ( third effectiveness ) test which is to... Stop pumping and hold for five seconds each wheel where the brake system indicator lamp activated... Condition of the CFR 3 ( 3791 Ratings ) brake test make sure the air pressure is 100psi! 2Tgfmsvk [ U __ @ mbn * 4z0|dr20dL @ l ` do this by turning the key to brakes... ( third effectiveness ) test capable of generating of cardboard or paper under wheel! Apply moderate pressure to the manufacturers instructions f `` cf ` ax? cz4 % 2TgFMSvk [ U @! F `` cf ` ax? cz4 % 2TgFMSvk [ U __ @ *. Run-Out or wobble in the system excessive lateral run-out or wobble in the system is capable of.! That they dont forget to turn off your engine before they start inspecting other of! S7.11 service brake can tap into for air tools, tire inflaters etc. ) pounds! Pedal to the wheels the condition of the parking brake test the bus headings control force readings be! Used on most large commercial vehicles and use compressed air to operate the brakes taking the bus &!