Engine Maintenance

Routine engine maintenance is important to optimize proper performance, fuel efficiency, clean exhaust and to protect water quality. Try creating and following a service schedule for your engine and check your owner’s manual for specific products and instructions.


  • Check fuel lines, tanks and vents for cracks, signs of damage and leaks.
  • Change fuel filters (used to remove particles/debris) and fuel separators (used to remove moisture/water) regularly and have injectors inspected annually. Carry spare fuel filters.


  • Oil should be changed regularly - create a step-by-step plan to reduce any accidents.
  • Temporarily disable your bilge pump, and after you change your oil, only turn the pump back on once you have checked for any contaminated oil or liquids.
  • Use a closed system to transfer oil, decreasing your chance of a spill.
  • When removing filters, place a strong bag around them to contain any drips.
  • Keep an oil absorption pad below the engine to catch leaks and wipe up any spills.
  • Proper disposal of oil is key to preventing runoff from land. When handled properly, oil and oil filters can be recycled. The EPA estimates that used oil from one oil change has the power to contaminate 1,000,000 gallons of water. Check with your marina to see if they offer collection of used oil for recycling, or use the search resources on Earth911.org to find your local recycling location.


  • If your engine has an air filter, make sure it is cleaned or changed regularly, and always carry spare filters.
  • Make sure air ducts are free from obstruction.


  • Check coolant levels before each trip. Antifreeze/coolant helps to transfer heat away from the engine, allowing it to operate at maximum efficiency. Most antifreeze (blue-green color) is highly toxic, poisoning an estimated 90,000 animals and 6,000 people in the U.S. each year (Humane Society of the United States and American Association of Poison Control Centers, respectively). Propylene glycol antifreeze (orange-pink color) is non-toxic, and has been proven to improve cooling by an estimated 60%. Antifreeze should be recycled and not poured down the drain or onto the ground.
  • Check impellers, stopcocks, pipes adn hoses for correct operation.
  • Inspect overboard discharge for correct flow without any contaminants (oil/fuel).

Outboard Maintenance

  • After each trip (fresh or saltwater), flush out your engine with freshwater. Most new outboards have a built-in flusher or you can use an “earmuff” flushing device.
  • Be sure to lubricate all moving parts such as the shift and throttle cables, carburetor valves, etc using environmentally friendly lubricants.

Waste Disposal

  • Use non-volatile organic compound solvents to wash engine parts and tools, and place them in a container where the dirty liquids can be collected and safely recycled or disposed.
  • Never dump waste oils, engine coolants or other toxic chemicals on the ground, into storm drains and dumpsters, or open waters.
  • Avoid mixing different hazardous liquids, which may make them unacceptable for recycling.
  • Ask your marina about disposal facilities for waste oils, liquids and associated byproducts.

Green Boating Guide: