How to Tune Up Your Lawn Mower?

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Do you get weary of tugging on the starting cord till it hurts your arm? If your lawnmower isn’t starting up as quickly as it should, it’s time for a tuneup.

Modern lawnmowers may frequently get by without a tuneup, but sometimes there might be glitches. 

Putting in a little work each spring can guarantee running smoothly for many years. There are a few steps that you should perform to make your mower work much more smoothly without making you sweat. Now let’s get started.

Tuning lawn mower

How to Tune Up Your Mower?

While owning a lawnmower entails additional normal maintenance responsibilities, the yearly tuneup process consists of only three steps:

  • Oil replacement
  • Spark plug replacement
  • Air filter replacement/cleaning

It would be better if the engine is a little warm before you do a tuneup. Fill the gas tank with just enough gas to get the mower started, then start the engine until the gas tank gets empty. 

Unplug the spark plug wire as a final precaution to prevent the engine from starting unintentionally.

Tools Required

Before initiating the tuneup process, you need to gather some tools listed below.

  • Motor oil
  • New spark plug
  • Rags
  • Wrenches
  • Old toothbrush
  • Screwdriver
  • Motor oil
  • Oil pan
  • Spark plug gapper tool
  • Paper towels
  • Grease-cutting soap

Step by Step Guide to Tune Up Your Mower

Now since you gathered all the tools that were required to tune up your mower, you are perfectly ready to start with the first step, which is replacing oil.

Oil Replacement

For oil replacement, first of all, you need to purchase new oil from the market.

Step 1: Purchase the Oil

You must be certain while purchasing the replacement oil. If in doubt, consult the owner’s handbook or the dealer where you purchased the mower. 

If you have misplaced the handbook, then you can most probably find the documentation for your mower online somewhere.

Step 2: Detaching the Spark Plug

To prevent the mower from being unintentionally started, unplug the spark plug wire. Simply slip the collar on the spark plug wire off the top of the spark plug to do this.

Step 3: Draining the Fuel Tank

Clean the exterior of the oil tank. If your oil tank has a dipstick, unscrew and remove it with an old toothbrush.

Locate the oil plug on the bottom of the mower. If you don’t clean the bottom of your mower on a regular basis, it may be coated with grass residue.

Prop your mower up on blocks, right-side up, with a small inclination toward the drain plug. Place a container beneath the gasoline tank and unscrew it to empty the tank. You’ll note how filthy the gasoline has become.

Step 4: Refilling the Tank With New Fuel

After making the fuel tank empty, you need to refill it with fresh fuel. Screw the tank tightly to avoid leaking.

Lawn mower tune up

Changing the Spark Plug

Now the second thing after replacing the fuel is, changing the spark plug. Let’s see how’s it done.

Step1: Removing the Old Spark Plug

The spark plug wire must be disconnected. It’s easy to remove it because all you have to do is slip the collar of the spark plug’s tip.

Using an old toothbrush, clean the spark plug’s outside. While removing the plug, it is vital to clean it to prevent dirt from getting inside.

Using a socket wrench and a deep socket, remove the old spark plug.

Step 2: Prepare a New Spark Plug

For information on the correct gap for the spark plug, consult the owner’s handbook, then modify the gap between the side electrode and the tip electrode to the proper distance. A gapper tool is the simplest method to accomplish this.

This equipment comes in different forms, but they all feature a way of measuring the spacing between the electrodes on a spark plug. The gap can be adjusted by bending the side electrode of the spark plug up or down.

Step 3: Installing the New Spark Plug

Using a socket wrench, tighten the new spark plug. Now reattach the spark plug wire to the top of the spark plug, then start the mower to make sure it’s working.

Changing the Air Filter

Congratulations on completing two out of three steps to tune up your mower. Now for the last step, you need to change the air filter of your mower.

Step 1: Removing the Old Air Filter

To avoid the possibility of an unintentional ignition, disconnect the spark plug wire. Remove the air filter cover by unscrewing it.

The cover is often fastened by a long screw that goes through the filter and is put into the bottom of the air filter housing or a wing nut threaded onto a bolt that runs through the air filter housing. 

The lid of the air filter may be removed when the screw or nut is removed.

Step 2: Installing a New Filter

Remove the old air filter and replace it with a new one with pleats facing outward. Now you must replace the air filter cover in its original position and secure it with the screw or wing nut. And then reconnect the spark plug and start the lawnmower to make sure it’s working properly.


With only these three yearly tuneups, most mowers will run well for many years. Only if this tuneup fails to keep your lawnmower going should you seek more serious repairs.

If the mower still isn’t operating correctly after the tuneup, see a professional.

About Tom Reynolds

My name is Tom Reynolds, and I like lawn mowing. When I was a kid, I used to help my dad in cutting grass using a reel mower, now, I have my own 6 different lawn mowers. Keeping my lawn healthy and beautiful gives me satisfaction, and I still enjoy working in my lawn.