To properly purge water from the fuel system, what must be drained?

To effectively purge water from the fuel system, it is essential to drain both the fuel strainer drain and the fuel tank sumps. Water can accumulate in various parts of the fuel system, particularly at points where fuel settles or where there are low spots.

The fuel strainer is designed to filter out debris and water that may be present in the fuel. By draining the strainer, you remove contaminants that have collected there. Additionally, the fuel tank sumps serve the same purpose, as they are areas where water can settle at the bottom of the tank due to its higher density compared to fuel. By draining both the strainer and the sumps, you ensure that you remove as much water as possible from the system, thereby preventing issues such as fuel line freezing, microbial growth, and potential damage to the engine.

In contrast, draining only the fuel strainer or just focusing on the lowest point may not be sufficient to effectively eliminate all water from the system. Just addressing one part could leave residual water elsewhere in the system, which could lead to ongoing complications. Thus, it is crucial to take a comprehensive approach by draining both critical components.