Cleaning an Outboard Motor Injector

When direct fuel injection -- or DFI -- technology revolutionized marine outboard motors in the mid-1990s, excitement was high. A June 1996 issue of "Popular Mechanics" listed DFI benefits including greater oil and fuel economy, fume elimination, better cold-starting capability, more-efficient power and torque delivery, smoother operation and overall reliability. But running an outboard motor is still a dirty business. The fuel injectors are especially prone to buildups of grime that can counteract fuel economy and cleaner emissions. Taking precautionary measures and performing appropriate maintenance, though, will help keep your outboard motor injectors in top shape.

Things You'll Need

  • Outboard motor injector cleaner
  • Higher octane gasoline
Show More

Instructions

    • 1

      Use higher octane gasoline for your four-stroke, DFI engine. According to the "Marine Engine Digest," you're not actually purchasing octane but a superior additive package that unplugs fuel injectors and scrubs carbon from the combustion chamber. Avoid fuels that contain more than 10 percent alcohol.

    • 2

      Add injector cleaner to your gas tank. Check with your motor's manufacturer or a repair manual for your motor, to see what cleaner you should use. Follow the instructions listed on the product's container.

    • 3

      Disassemble and clean the injectors. Even the best additives can't clean some of the dirtiest injectors. Follow instructions specific to your engine. If the job goes beyond your expertise or comfort level, bring your engine to a professional outboard motor mechanic.

    • 4

      Add fuel stabilizer to your gas tank. This is especially important when you'll be storing your boat for over two weeks. When stagnant, gas breaks down and will quickly dirty your injectors the next time you run your boat. After adding the stabilizer, let the engine idle for 10 to 20 minutes so that it spreads throughout the entire fuel system.

    • 5

      Disconnect fuel lines from engine, as another method to prevent stagnant gasoline from clogging your injectors. After you've added stabilizer to your gas tank, instead of idling the engine for 10 to 20 minutes, disconnect the fuel line from the engine while still it's running, and wait for the engine to stop. This burns up the remaining gas in the fuel components.