ASE S2 Diesel Engines (School Bus) case studies
ASE S2 Diesel Engines (School Bus) · Put your knowledge to work in context.
ASE S2 Diesel Engines is one of the specialty credentials in the ASE School Bus certification series. It certifies that a technician can diagnose, adjust, and repair the diesel engines used in school bus applications, including the engine block and valve train, lubrication and cooling, air induction and exhaust, fuel injection and governing, engine braking and electronic controls, starting and charging, and emissions aftertreatment. The ASE S2 Diesel Engines (School Bus) case studies are 5 cases and about 2,344 words.
1Overheating School Bus on a Morning Route With Rising Coolant Temperature and Low Fan Engagement
A 2016 conventional school bus with a Cummins ISB 6.7 runs a 42-mile morning route with 31 stops. The driver reports the coolant temperature gauge climbing from 195°F to 228°F only on the route, never on the highway.
501 words, about 3 min2Low Oil Pressure Warning at Hot Idle on a Rear-Engine School Bus
A rear-engine transit-style school bus with a 2013 MaxxForce 7 has 148,000 miles. The dash displays a low oil pressure warning at hot idle after a long run, but the warning clears as soon as engine speed rises above 1,100 rpm.
461 words, about 2 min3Hard Start and White Smoke on a Cold Start With Suspect Glow System
A 2014 school bus with a 6.7L Power Stroke cranks 8–10 seconds before firing when cold (40°F), runs rough for 20 seconds with white smoke, then smooths out. Once warm it restarts instantly.
418 words, about 2 min4Engine Brake Inoperative Below Set Speed With Jake Brake Switch On
A 2015 conventional school bus with a Cummins ISL 9 and an integrated compression-release engine brake is used on a hilly route. The driver reports the engine brake works above about 35 mph but does nothing below that, even with the switch on and the transmission in a low gear on a long downgrade.
487 words, about 2 min5No-Crank on a School Bus With Good Batteries and a Suspect Starter Circuit
A 2017 school bus with a 6.7L Cummins will not crank. The dash lights come on, the headlights are bright, and the batteries measure 12.7V at rest and 12.4V when the key is turned to start.
477 words, about 2 min