How To Replace Toro Lawn Mower Spark Plugs? – Complete Guide

How To Replace Toro Lawn Mower Spark Plugs?Have trouble turning your lawn mower ON? Well, the reason can be the spark plug in the lawn mower. You might be familiar that the little spark plug produces a powerful spark that helps to kickstart your lawn mower.

If your spark plug does not start and gets fouled or worn out, you might not be able to start the engine since the key to the engine is the spark plug. You can start by looking if any debris is restricting the spark plug. If you have tried different methods, but none worked, you might need to replace your spark plug with a new one. A damaged spark plug can reduce the longevity of your lawn mower and increase fuel consumption. Keep a check on your spark plug and keep replacing it when needed.

This article will demonstrate how to replace the Toro lawn mower spark plug.

You can also learn how to troubleshoot the issue of “Lawn Mower Starts Then Stops” in our guide.

What Are The Ways To Change Toro Lawn Mower Spark Plugs?

After 100 hours of using the lawn mower, Toro recommends the users check out the spark plug. However, the company also says that users can replace the spark plug if they have used it for 200 hours. People overgeneralize and think replacing the spark plug at home is impossible. This myth is not the case. You can easily replace the Toro lawn mower spark plug with some basic tools, and that too at home.

Things you will require:

  • Spark plug wrench
  • Socket wrench
  • New spark plug

Read owners manual

Read owners manual

One of the best practices before starting the replacement of the spark plug is reading the manual. Every lawn mower comes with an instruction guide handbook or pamphlet. You can go through the instructions first. This step will familiarize you with the different parts of the lawn mower and how to replace the spark plug. However, if you lost the owner’s manual, do not worry. You can consult this page to nail the job with a few simple steps perfectly.

Encountering issues with your lawn mower’s pull cord? Learn how to troubleshoot and fix this problem with our guide on ‘Lawn Mower Pull Cord Not Catching for a seamless mowing experience.

Remove The Spark Plug Wire

First of all, you need to disconnect the lead of the spark plug. It will rescue you from an accident.

  • Reach out to the spark plug lead.
  • Gripp the wire with your hand, and pull it outwards.
  • The rubber lead will come out.
  • Look at the connector and lead.
  • Make sure the condition of the connector and plug is good, and no debris is sticking to them.
  • If you notice any debris, clean it from the surrounding areas so the combustion chamber is clean.

Remove Spark Plug Connector

Remove spark plug connector

Before starting any process, it is important to take safety precautions. Wear gloves, goggles, and keep the main electrical connections off if your lawnmower is electric. Once you have detached the spark plug wire, it is time to remove the spark plug with the help of a wrench. Spark plug wrenches are the best choice as they have an inserted rubbed in them. The rubber in the spark plug wrench will hold the porcelain insulator with protection and grip. Do not use a deep socket wrench. It can crack the spark plug.

Observe Firing End

Once you have taken out the spark plug, look into the firing end. You can observe a lot by looking at the firing end. If the end is grey in color or tanned, it means your spark plug is fine, and you do not need to change it.

However, if the plug’s firing end is wet, you must dry it out. The firing end can be wet due to engine flooding. If the engine is over-primed, it causes flooding. Another reason can be choke malfunction.

Let the firing end dry, fix it again, and try to start the plug. If it starts, then do not replace the plug. However, if it does not start, you must replace it with a new one.

If you observe that the firing end is worn out and black, consider buying a new one and replacing it with the older one.

Assemble The New Spark Plug

Once you have the new spark plug, change it with an older one. Usually, the gap is perfect if you know the engine’s model. In case of any doubt, you can check the gap in the spark plug by using the plug gapping tool.

  • Take the spark plug connector, and assemble it in the engine by using your hands.
  • This will ensure that the spark plug is sitting well with the threads and will tighten well.
  • Now use a wrench and tighten fully until the plug is completely compressed. Place the wire back on the connector.
  • Your new spark plug is all set to start the engine.

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Toro lawn mower spark plugs get problematic sometimes. The company recommends replacing the spark plug after 200 hours of using the lawn mower. However, in ideal situations, you can also check the spark plug and its wire after 100 hours of use. You can take out the old spark plug, and check the firing end. If it is grey, then you do not need to replace it. However, if the spark plug’s firing end is wet, you can dry it out.

Then place it back again. You must change the spark plug if the firing end is worn out and black. Assemble the new spark plug initially with hand to avoid cross-threading. After that, you can tighten it with a wrench. Connect the plug wire and start the engine.