How To Replace A Spark Plug & Air Filter On A Honda Mower Main Image

To obtain the best life out of your engine, make sure you check the air filter for built-up dirt or debris. A dirty air filter can allow the filter to let sediment and debris pass through and into the engine. Dirt ingestion can damage an engine fairly quickly, so make sure you always have an air filter equipped and check to make sure it's clean.

Here's a quick recap of the video:

Replacing The Air Filter

  • On this particular Honda lawn mower, you'll need to carefully push down on the two retaining clips on the outside of the air filter cover. There are two hinges on the bottom of the air filter cover, carefully clear the hinges from the clips and remove the air filter and air filter "box" (or cover).
  • It's a good idea to clean the air filter cover and the box before re-installing your replacement air filter.
  • Place the new air filter back onto the mower in the same direction as the old filter. On this Honda lawn mower, we're going to replace the filter with the fins pointed outward.
  • Place the hinges back into the pins and snap the air filter cover back into the retaining clips

Replacing Your Spark Plug

  • Disclaimer (because we have to): Always make sure your engine is off before performing engine maintenance. We want you to start and finish this job with the same appendages God gave you.
  • The spark plug is traditionally located on the front of the lawn mower. On this Honda lawn mower, it is located in the upper front hand portion of the mower, directly beneath the red engine shroud/cover.
  • Carefully put your index finger in between the engine and the cap. To remove the cap, grasp the cap firmly, pulling and twisting at the same time to remove the rubber cap. It will eventually slide off. Sometimes the cap can be stubborn, but be patient and it will eventually come off.
  • We recommend using a spark plug socket. This is a special socket with a rubber seal that grips the spark plug while removing it. The Honda mower we're working on today uses a 13/16" socket.
  • Carefully remove the spark plug using a socket wrench. We also recommend using a socket wrench extension to make your job easier -- turning a socket in close proximity to the engine shroud can be difficult.
  • Before installing the new spark plug, check the spark plug gap/clearance for the electrode air gap. This can be obtained from your local servicing dealer or from your machine's owner's manual or service manual.
  • It's a good idea to lightly oil the threads of the spark plug before installation. This will help you remove the spark plug on your next tune-up.
  • Always start by hand tightening your spark plug into the cylinder. You do not want to use your wrench to start your spark plug as this may damage the threads on the cylinder head -- this is a costly repair!
  • When re-installing the spark plug cap, you'll want to take the cap and firmly push the cap over the plug. You should hear it snap into place.