How to Tune up a Lawn Mower?

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In this timely post we will enumerate steps to take to tune up your lawn mower. If you use your lawn mower on a regular basis it should be more prone to excessive use that could lead to wear and tear. Regular maintenance is needed to ensure it doesn’t sputter when you need it the most.

Of course, you can take the easy route of paying roughly $70 to a professional to tune up your lawn mower if you have the funds.

However, tuning up your lawnmower is not as difficult as it should be and with a little DIY skill, in less than an hour, you should be done.

How to Tune up a Lawn Mower
  • Socket Wrench
  • Spark Plug Wrench
  • Screwdriver
  • Oil drain pan
  • Working gloves
  • New Air Filters
  • Gasoline and replacement oil

1. Disconnecting the Spark Plug

The first step to take to tune up your lawnmower is to disconnect the spark plug. It’s one of the first and foremost precautionary measures to take to avoid accidentally starting up the lawnmower and avoid potentially hazardous conditions.

Locate the spark plug wire and use your hand to disconnect the rubber boot to reveal the plug. Then use the spark plug wrench to disconnect the plug.

Right Spark Plug for Lawn Mower

2. Drain Off the Oil

After you have successfully disconnected the spark plug the next step is to drain off the oil from the engine. You should consult the owner’s manual to find out how to go about draining of the oil or search online for the proper procedure to follow.

Ideally,  you will find a drain plug located at the undercarriage of most push mowers.  Remove this plug to drain the oil in collecting can.

You can also drain off the oil through a fill tube. Just tilt the lawn mower on its side and use the fill tube to dream of the oil in a collecting pan.

3. Replace the Air Filter

Air filters are an intricate part of lawn mower engine. They filter the air of impurities making sure there is a homogeneous mixture of air and fuel for proper combustion.

Occasionally these air filters can get clogged with dirt which will in turn affect the engine’s performance. By using a screwdriver remove the air filter cover and replace it with a new one.

4. Remove the Blades

Remove the blades and replace with sharper blades to help your lawn mower run smoothly and offer a healthier grass cut.

Place a block of wood opposite the blade in the direction in which you want to loosen the main bolt that holds the blade in place. Then use the correct wrench to loose out the blades.

5. Sharpen the Blades

How to Sharpen Lawn Mower Blades

The steel of most lawn mower blades is soft and do not require much effort to sharpen. They don’t even have to be super sharp, they just have to be sharp enough to give you a nice cut. You can either use a file, bench grinder or machine to sharpen the blades.

Unless there are substantial dents in the blade, just sharpening out last year’s grime is more than enough to give a new sharp edge to the blade.

While the blades are off the mower for sharpening, take out time to clean out the scrape off the inner layers within the lawn mower. There is usually gunks of grasses hidden within those layers.

6. Change the Spark Plugs

Go online or to a machine shop to buy the right replacement spark plug. Ideally, the new spark plug should have a gap between the electrode and the arm. There must be a gap to generate a spark.

Insert the new spark plug with your hands in the spark plug port before using the dedicated wrench to tighten it.

7. Replace the Oil and Gasoline

By now, you should have bought replacement oils and new gasoline to use. Most push lawn mowers use oils of the type SAE 10W-30. Before putting in new oils, ensure that you have inserted the drain bolts to the undercarriage. Motor oils cost about $3.

Add the fresh gasoline after removing the old gasoline.

8. Reconnect the Spark Plug Wire

Finally, reconnect the spark plug wire to the cap of the newly inserted spark plug. You must be sure that you have completed all other tasks before you reconnect the spark plug wire. Now you are ready to start the lawn mower.

Let’s Recap Your to-do-list 

  • Disconnect the spark plugs before you start the tune up process
  • Drain off the oil from the engine
  • Replace the air filters if they are clogged
  • Remove and sharpen the blades
  • Change the spark plugs
  • Replace the oil and gasoline before reconnecting the spark plug wire


Spraying the underside of your lawn mower with a nonstick spraying paint will dramatically reduce the build-up of gunky grass on the inside. Regularly cleaning with a damp cloth also will increase the shelve life.


Tuning up your lawn mower to ensure it works smoothly is easy but you still have to decide if you have the time for it. The tips enumerated here are the basics of what you should do each year or after the prolonged winter season. However, if you live in dusty areas you might need to repeat some of the maintenance steps more than others.

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