Practice question

A school bus diesel runs hot only at highway speed and load, but stays normal in town. The MOST likely cause is:

  1. A reduced cooling capacity issue such as a partially plugged radiator core, debris-blocked charge air cooler/radiator face, or a slipping fan/clutch under high heat load
  2. A stuck-closed thermostat
  3. A faulty cabin blower
  4. A worn brake rotor

Answer: A — A reduced cooling capacity issue such as a partially plugged radiator core, debris-blocked charge air cooler/radiator face, or a slipping fan/clutch under high heat load

The correct answer is shown above. Try the full quiz for additional practice.

Practice more: ASE S2 Diesel Engines (School Bus) Practice Questions - ASE S2 - Diesel Engines (School Bus) Certification Exam →