Yanmar UTV Spark Plug Change

How Do Spark Plugs Work?

Spark plugs are a key component of combustion engines. They provide the electrical spark within the engine that ignites the fuel/air mixture in the combustion chamber. Spark plugs sit at the top of the cylinder head. As the piston travels down the cylinder and then pushes the compressed mixture upward, the spark plug fires at the peak of the piston’s upper reach, creating the ignition that ultimately helps power the vehicle.

It’s important to note that spark plugs are only found in gasoline-powered engines. This is one of the key differences between gas and diesel UTVs.

How to Change the Spark Plug on Your Yanmar UTV

Changing spark plugs is one of the easier maintenance items for your UTV. The condition of the spark plug can often help determine the condition of the engine. Looking at the porcelain insulator around the center electrode, it should be a medium to light-tan color for a vehicle being ridden normally.

Now that you know what to look for in the condition of your spark plug, here’s everything you need to know to change it.

Tools Required for Spark Plug Change

Your spark plug change only requires a few basic tools. This list includes:

Ratchet
? Spark Plug Socket
5-Inch Extension
Spark Plug (Part #NGK/CPR7EA-9)
Spark Plug Gapper Tool
Gloves
Torque Wrench

Spark Plug Change Instructions

Once you’ve gathered your tools, you’re ready to get started on changing your spark plug. These are the steps to follow.

Before replacing your spark plug, ensure the engine is cool to the touch. To locate the spark plug, lift the lever to raise the UTV bed.
Locate the spark plug wire boot and pull it off. This will give you access to the spark plug.
Using your ?-inch spark plug socket, set it down on the spark plug, and turn to remove.
Grab your replacement spark plug and the spark plug gapper tool, setting the gap on the new spark plug to 0.031-0.035 inches.
With the gap set, reinstall the spark plug. First, finger tighten the spark plug. Then, use the torque wrench to torque the plug to 9.4 ft-lb.
Finally, reattach the plug wire boot and plug wire to the spark plug. Your spark plug change is now complete.

Connect With Yanmar

At Yanmar, we want to ensure you get the most out of your UTV, tractor, and attachments. From service tutorials to updates on the latest technology, our Customer Experience Team is here to help. Please don’t hesitate to connect with us online or give us a call at 678-551-7369.