What is the recommended practice to minimize contamination of the engine from dirt and water?

Straining the fuel from the lowest points in the system is indeed the recommended practice to minimize contamination of the engine from dirt and water. This method is effective because contaminants tend to settle at the lowest points in the fuel system due to gravity. By accessing these low points, the pilot can remove both dirt and water that may have accumulated, thereby preventing them from entering the engine and causing potential damage or performance issues.

In aviation, maintaining fuel quality is critical as any foreign particles or water can lead to engine malfunction or failure. By ensuring that fuel is clean before it enters the engine, the overall reliability and safety of the aircraft are enhanced. This process aligns with standard procedures in aviation maintenance and is an essential checkpoint before flight.

Other practices, while important for overall safety and maintenance, do not specifically target fuel contamination from dirt and water in the same effective manner as straining from the lowest points. Regularly checking engine filters and filtering fuel after refueling are both helpful practices to maintain cleanliness but may not directly address the immediate risks associated with sediment and water that naturally settle in the system. Using higher grade fuel does not inherently reduce the risk of contamination from dirt and water either.