Instruction Manual

28
Defi nitions
 Transporting students to and from school and/ or school related events
 Operation on road surfaces of concrete, asphalt, maintained gravel, crushed rock, or hard packed dirt
 Two (2) stops per mile are considered typical
 100% load going / empty return (typical)
Typical Vehicle Types
Front Engine Commercial Chassis Front Engine Integral Coach
Rear Engine Integral Coach
Vehicle Confi gurations
4 x 2 straight bus
General Requirements
• Anti-compounding air system
• Cam same operation for all brakes
• Air chamber bracket with gusset for all school bus applications, see page 45
• Air chamber bracket assembly gusset and additional camshaft bracket support see page 45, attached to the axle housing
when the:
a. Brake centerline to air chamber centerline distance (BCCC dimension) is greater than 343 mm [13.5”]
b. Application use a type 30/36 or 36/36 Spring brake chambers.
c. Camshaft brackets with BCCC dimension of less than 8.12" does not require a gusset or additional support.
d. Super Single Tire (Wide Base)
Note: The above support can be supplied by BSFB or the vehicle manufacturer but
must be approved by BSFB Application Engineering Department.
• Applications for use in countries other than the USA and Canada must be reviewed by BSFB Application Engineering.
• Vehicle manufacturer is responsible for air system design, parking and stopping distance performance.
• For all S-cam brake models the camshaft input torque is limited to 2545 N•m [22,500 in-lbs].
• Applications on vehicles with fi xed or liftable auxiliary axles (tag or pusher) must be approved on an individual basis by the
BSFB Application Engineering Department, as auxiliary axles may impact the braking performance of the vehicle.
General Recommendations
• Dust shields for all applications
• Use Auxiliary retarders per TMC RP636
• Brake drum / Rotor material specifi cation per SAE J431. Drum / rotor surface fi nish 4.57 micrometers [180 max microinch]
and .38 mm [.015"] runout, when mounted on a hub rotated on bearings. See notes section for Minimum Drum Weight
requirements
• Brake air system balance per TMC RP632
School Bus