“When I do an inspection, I look at
the fractional amount of lining left on the shoe,” said Alan Fidler, a bus technician from Tippecanoe School Corporation in Lafayette, Ind., and the 2011 and 2012 America’s Best National School Bus Technician winner. “Our state spec is ¼-inch at the center of the shoe, so if there is a shoe on one axle that is close to the minimum, then that axle gets a complete brake job.” “Shoes, hardware and drums get re-
placed,” he continued. “Since we use auto slack adjusters, I also check the installation and operation of the auto feature to ensure they are working to the manufacturer’s specifications. I also do not back off auto adjusters any further than needed to remove the drum, then crank them around until the s-cams are at the fully released position. Tis saves the wear on the automatic part of the adjuster. We also use a ceramic extreme brake parts lubricant on the anchor pins, bushings and inside edges of the web to reduce rust-related problems.” Lake said his district checks brakes at
every 2,000-mile service interval, unless a specific concern is previously reported. Te annual DOT inspections also mark the date for a six-month inspection. “We update the form at each 2,000-mile
interval to ensure that the six-month inter- val is not missed. If there is any wear out of spec, it is our internal policy to replace all brake related parts including drum, shoes, and hardware with all new parts,” he explained. “Specific attention is given to brake cam wear. If out of spec, bushings are replaced. Many of our buses would meet the 2,000-mile interval before the 30-day timeframe. Obviously brake wear is one of our top priorities of vehicle maintenance.” LaRocco at the Indiana Department of
Education said defining and implementing appropriate work processes are an extremely important starting point for any mainte- nance department. “Unfortunately, if the mechanics tasked with following those processes are not being
66 School Transportation News March 2013
properly supervised, evaluated regularly and held accountable for not following the proper processes, then just having a process in place will not be effective in maintaining the level of safety necessary for school transportation,” he said. “Every safety innovation in the school transportation industry is only effective if the school bus drivers, monitors, mechanics, and supervisors are dedicated to continue provid- ing the safest possible transportation for our most precious cargo: children.”
ARE CANADIAN SCHOOL BUS INSPECTIONS ANY DIFFERENT?
In British Columbia, a typical PM and inspection program would be very similar to that in the U.S., including mechanical and air-system regulations. One difference is the use of cam rotation meters on each brake s-cam that monitors the degree of travel. A bus is out of service once the rotation reaches 120 degrees, which indicates excessive drum and brake shoe wear. Brakes are replaced well before maximum rotation travel is reached. In addition, the foundation brake backing
plates must be removed (permanently) to aid in a visual inspection during this process. Te PM program is covered by regular services, six-month in house inspections and yearly gov- ernment decal inspections performed by school district technicians. Te commercial vehicle Safety and Enforcement (CVSE) inspector also inspects each school bus once a year. As mentioned, every school district mainte- nance facility has to follow DOT regulations
£ Alan Fidler of Tippecanoe (Ind.) School Corporation performs the preventive maintenance check of brakes during a scheduled service.
and any pertinent state laws or policies for an- nual and semi-annual school bus inspections. While different states and provinces have slightly different PM programs set up, the amount of times a school bus is inspected far exceeds any other vehicle on today’s highways. Prevention is the key word with any fleet of buses, and avoiding mechanical failure is a top priority. It’s safe to say that fleets that follow the above criteria have the safest vehicles on the road. “All fleet operators must follow the U.S.
Federal Motor Carrier Safety Administration regulations (FMVSA) outlined under Fed regulation 396 as a minimum requirement and in addition, understand all the various state and provincial requirements for annual or semi-annual brake inspections,” said Robert Pudlewski, proprietor of Fleet OPS Consulting, LLC and STN’s technical editor. “Tis would have to be considered when developing your inspection process. Te most critical item for any school bus operator is to make sure they are in compliance with Fed regulation 396.25 (qualification of brake inspector) which mandates that an operator complies with having completed certification of a mechanics ability, knowledge to inspect and work on brake systems.”
Ü AUTOMATIC SLACK ADJUSTER NOT FOR MANUAL ADJUSTMENT In 2006, the National Transportation Safety Board issued technical bulletin No. H-06-8
that stated the dangers of adjusting auto slacks manually. Bendix Spicer Foundation Brake LLC said there is potential danger if an auto slack is
adjusted manually to compensate for the slack adjuster failing to auto adjust or to com- pensate for faulty foundation brakes. Continuing to manually adjust an auto slack will give the operator a false sense of security with brake effectiveness. It can be manually adjusted only in an emergency situation, as a one-time temporary measure. Routinely adjusting an auto slack will also cause premature failure.
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