For engine operations, what must be maintained to avoid damage during start-up?

• A. The temperature must exceed -20 C
• B. The oil temperature must be below 25 C
• C. The oil pressure must be above 55 psi
• D. The outside air temperature must be above -25 C

Answer: (D)

To prevent engine damage during start-up, it is crucial to ensure that the outside air temperature is above -25 degrees Celsius. Cold temperatures can significantly impact the viscosity of engine oil, which may become too thick to circulate properly. This thickening can lead to insufficient lubrication of engine components during the critical start-up phase, increasing the risk of wear or potential engine failure.

Maintaining an outside air temperature above this threshold allows the engine's oil to remain within acceptable viscosity levels, promoting proper lubrication and ensuring that the engine operates smoothly as it starts. This practice is essential for protecting the engine's internals from damage that could occur due to inadequate lubrication in extremely cold conditions.