Definitions of check out:

• verb:   record, add up, and receive payment for items purchased
• verb:   try to learn someone's opinions and intentions
• verb:   announce one's departure from a hotel
• verb:   withdraw money by writing a check
• verb:   trace
• verb:   be verified or confirmed; pass inspection
• verb:   examine so as to determine accuracy, quality, or condition

  Example: "Check out the engine"