Edith Bryant March 25, 2020

If you own a lawn mower, you likely know that it requires some maintenance from time to time. Occasionally, you may find that it is unusually hard to start. This can cause some worry even for people who are experienced working with car parts. Fortunately, a lawn mower isn’t that different from a car or truck. Furthermore, learning how to fix basic problems is easy.

The Problem

There are a number of issues that could be causing the problem. The most common problem and the simplest to fix is that the spark plugs need to be cleaned or changed. Other issues may be a problem with the fuel system, an issue with the starter crank or a dead battery.

These latter issues may require some help from an experienced lawn mower technician. However, checking and changing the spark plugs is something anyone can learn to do. Even if you have never changed your car spark plugs, you can learn how to do it for your lawn mower in about ab hour.

Changing Your Spark Plugs

You should be checking on your spark plugs every year or whenever you are experiencing problems starting. Other symptoms of bad spark plugs include poor fuel efficiency and the engine stopping unexpectedly.

To start, you need to identify the right type of spark plug to buy. You can determine this by looking in your owner’s manual or by checking the number on the ceramic insulator on your existing spark plug. Alternatively, take your existing spark plug to the store. Many places will be able to help you find the right replacement.

  1. Position: Start by getting the lawn mower on a flat, stable area. A garage floor is perfect if you have room. Otherwise, a patio or other flat area can work.
  2. Disconnect: Locate the spark plug wire. This may require you to remove the engine cover. Disconnect the wire from the current spark plug.
  3. Remove: Loosen the existing spark plug with a socket wrench. Fit the spark plug socket over the plug and turn gently. If you can’t easily loosen the plug, try lubricating it.
  4. Clean: Clean the old spark plug with a wire brush and/or spray-on spark plug cleaner. You may be able to continue using the existing plug just by cleaning off some of the fouling.
  5. Adjust: Adjust the gap between the curved and straight electrodes using a gauge. This should match the old plug.
  6. Replace: Whether you need a new spark plug or continue to use the old one, put the spark plug in the slot. Turn it until it is hand tight then go a little further with the socket wrench.
  7. Reconnect: Connect the spark plug wire to the spark plug. You are done!

Get Started

Now that you know how to deal with your spark plugs, you can likely fix your lawn mower when it isn’t starting properly. Checking on and changing your spark plugs is easy and relatively inexpensive. It should always be your first step when trying to fix a starting issue.