Spark plugs are vital components of your Evinrude outboard motor, ensuring efficient combustion and smooth operation. Regularly inspecting and replacing spark plugs can prevent engine problems and maintain optimal performance. In this article, we'll guide you through the signs that indicate it's time to replace your spark plugs, how often to check them, and the steps involved in replacing them.
Why Spark Plugs Are Important
Spark plugs ignite the air-fuel mixture in the engine cylinders, creating the explosion that powers your outboard motor. Over time, spark plugs can wear out, leading to poor engine performance, increased fuel consumption, and difficulty starting the motor. Regular maintenance and timely replacement of spark plugs are essential to keep your Evinrude outboard running smoothly.
Signs That It’s Time to Replace Spark Plugs
-
Difficulty Starting the Engine: If your motor struggles to start or requires multiple attempts, worn-out spark plugs could be the culprit.
-
Engine Misfires: Misfiring or uneven running can indicate that spark plugs are not igniting the fuel mixture properly.
-
Poor Fuel Economy: A noticeable drop in fuel efficiency often points to spark plugs that need replacing.
-
Rough Idling: If the engine idles roughly or stalls frequently, it could be due to faulty spark plugs.
-
Loss of Power: Reduced engine power, sluggish acceleration, or difficulty reaching higher speeds can result from worn spark plugs.
-
Visual Inspection: Removing and inspecting the spark plugs can reveal their condition. Look for signs of wear, such as erosion, deposits, or a fouled appearance.
How Often Should You Replace Spark Plugs?
The frequency of spark plug replacement depends on various factors, including your engine model, usage, and the type of spark plugs used. Here are some general guidelines:
- Standard Copper Spark Plugs: Replace every 100 hours of operation or annually, whichever comes first.
- Platinum or Iridium Spark Plugs: These types can last longer, often up to 300 hours or three years, depending on usage and manufacturer recommendations.
How to replace Evinrude spark plug:
Remove ignition coil above spark plug to gain access. When reinstalling coils, tighten screws to a torque of 60 to 84 in. lbs. (7 to 9.5 N·m)
Indexing:
Spark plug indexing positions the ground electrode of the spark plug opposite the fuel injector nozzle. Put an ink mark on the ceramic of the spark plug in line with the OPEN side of the ground electrode. This mark will be used to orient the spark plug with the OPEN side of the ground electrode facing the fuel injector.
1= Ink mark
2= Open side
Apply Triple-Guard grease to the gasket surface of the spark plug. Install spark plug and tighten to a torque of 15 ft. lbs. (20 N·m). If the mark is in unshaded area do not tighten anymore
1= Unshaded area
2= Shaded area
If the mark is in the shaded area, reset torque wrench to 30 ft. lbs. (41 N·m) and continue to turn until the mark is in the unshaded area. If the mark does not reach the unshaded area before the torque of 30 ft. lbs. (41 N·m) is reached, the spark plug cannot be indexed for that cylinder. Try another spark plug and repeat the steps above.
