When faced with a leaking needle and seat style check valve, what should a pilot do first?

When confronted with a leaking needle and seat style check valve, the first action a pilot should take is to pull up on the needle. This action is aimed at reseating the needle within the valve, which can fix the leak. The check valve relies on the needle making a proper seal to prevent fluid from leaking. By pulling up on the needle, the pilot may be able to achieve the necessary contact and establish a proper seal, resolving the leak without needing immediate replacement or further inspection.

The other options represent potential next steps but do not address the immediate need to try to stop the leak first. Replacing the valve may ultimately be required, but it is typically a more involved process that can be avoided if the issue can be resolved through simple adjustments. Inspecting the hoses is useful for understanding the overall condition of the system but does not directly address the leak from the check valve. Flushing with water might help in some contexts but would not resolve the mechanical issue of the needle not seating properly. Therefore, attempting to fix the leak by adjusting the needle should be prioritized.