CDL · Night and weather
The cooling system of your engine is hot. At what point can you safely open the radiator cap?
Correct answer: Only once the engine has fully cooled.
Answer options
- AAs soon as you turn the engine off
- BWhenever the gauge shows the engine is not overheating
- COnly once the engine has fully cooled Correct
Why
A hot cooling system is under pressure, and opening it can blast scalding steam and coolant at you. Wait until the engine has cooled all the way before removing the cap, even if the gauge no longer shows overheating.
Tip A good rule is to leave the cap closed until it is cool enough to touch safely with your bare hand.
About this question
Topic: Night and weather License: CDL
Part of these practice sets:
Where it applies: Asked in every state.
Practice the whole set
This question is part of Winter, Hot Weather and Wind (12 questions). Take the full set and check your score.
Practice Winter, Hot Weather and WindMore questions from Winter, Hot Weather and Wind
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