Paul Todd/Outside Images photo

You’ve probably heard this advice before, but make this the year to actually follow it. Impellers are inexpensive and easy to change as long as they are intact. But it gets messy when they disintegrate and you’re left fishing chunks out of the engine’s heat exchanger. Access the impeller through a plate in the engine’s raw-water pump. Remove the O-ring and pull out the impeller, taking note of which direction it faces. Put in the new impeller and check the O-ring to make sure it is still malleable, replacing it if necessary. Then close the pump up and check this simple step off your list.

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