Within what time frame must the engine oil level be checked after engine shutdown?

The correct response relates to the guidance provided for checking the engine oil level after engine shutdown, which is a critical procedure in ensuring the proper functioning of the engine. After an engine shutdown, oil will typically settle back into the oil reservoir due to gravity, providing a more accurate measurement when checked after a certain period.

The timeframe specified in the correct answer of 3 minutes to 2 hours accounts for the need to allow the oil to fully drain back into the sump for a reliable reading. Checking too soon may result in an inaccurately low reading due to oil remaining distributed throughout the system or in the engine components, not reflecting the true oil level in the reservoir. Conversely, waiting too long, such as beyond 2 hours, could be outside the maintenance guidelines and may lead to differing temperatures or oil conditions affecting the reading.

Thus, the range provided in the correct answer balances the need for accuracy with practical considerations in the operational environment of the CRJ 200.