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What is the purpose of the governor in relation to the tachometer's red zone?
- A.The governor makes redline operation safe
- B.The governor limits maximum engine rpm to protect the engine; operating at or beyond the redline, especially engine braking downhill, can still damage it
- C.Redline is the recommended cruise range
- D.Governors only limit road speed
Correct answer
B. The governor limits maximum engine rpm to protect the engine; operating at or beyond the redline, especially engine braking downhill, can still damage it
Why
Even with a fuel governor, a downgrade can force the engine past safe rpm through the wheels, a condition called engine overspeed on the descent. Gear selection before the grade is what keeps rpm inside the safe band the tachometer shows.
Manual topic: Engine Controls - Governor · From the General Knowledge practice bank (GK-379).