How To Replace The Battery Of Lawn Mower

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It’s a beautiful day, and the brilliant sunshine has inspired you to clean your yard. You go to get the Lawn Mower out, and just as you were ready to begin, the Lawn Mower refuses to start.

There could be a number of reasons for this, including dust in the air filter of your engine, a dead battery, or anything else.

Let’s narrow it down by looking at the most likely cause: a dead battery.

But wait a second. How do you know if the battery is dead? How to replace the battery? Do you have these questions in your mind? Get answers to the most common questions and also verify whether the battery is actually dead by simply reading this article.

Now let’s get started.

How Will You Know If the Lawn Mower’s Battery is Dead?

If your lawn mower is not working, the first thing that will come to your mind will be that it may be due to the battery not working. But how will you confirm this?

Just try to do this!

  • Set the multimeter to DC to check the voltage of the battery. If it’s 12.7 DC volts or higher, the battery is fine and something else is causing your startup issues, otherwise, it’s time to replace the battery.
Replacing old battery of  lawn mower

How to Replace a Battery of a Lawn Mower?

Now since you know that the fault is in your battery, you must be thinking about how to install a new battery to clean your yard.

Here are a few steps, just follow them to replace your old battery with a new one.

  • If your battery got finished while you were using it then make sure your Lawn Mower is parked on a level surface. 

Let the blades and all moving parts come to a complete halt after turning off the engine. Allow a few minutes for the lawnmower to cool.

  • Now inspect your Lawn Mower and look for the battery. The battery in a Lawn Mower can be found behind the seat or under the hood.
  • To protect yourself from battery acid, put on protective glasses and gloves.
  • There are chances for corrosion in your lawn mower battery, especially the point that connects the battery cables to the terminals. To dissolve any corrosion prepare a baking soda mixture.
  • To prepare the baking soda mixture, add 1 cup of water, 1 tsp of baking soda in a disposable cup. Thoroughly mix the contents with a spoon to dissolve the baking soda.
  • Then, insert a flat-head screwdriver into the battery-stabilizing bracket, if your lawnmower has one. To release the screw, turn it counterclockwise and move the bracket to one side.
  • To loosen the negative terminal, insert an adjustable wrench on it and turn it counterclockwise. The black battery line is linked to the negative terminal, which has a “-” sign on it. 

In the same way, detach the positive, red battery cable. Remove each battery cable from the old battery by pulling it up and out. Now remove the old battery from the battery box and set it aside using the middle handle.

  • Each battery cable should have the pointed end of a battery terminal cleaner inserted into it. To remove any rust or corrosion that is preventing the battery from performing correctly, turn the cleaner in a circle.

Each cable should be cleaned until the insides of the circles are gleaming. Now use a shop towel, wipe away any excess metal shavings.

  • Fill the box with the new lawnmower battery. Add a thick layer to the new battery terminals with a forefinger dipped in petroleum jelly. The fresh battery will not corrode as a result of this.
  • Use an adjustable wrench to tighten the red positive battery connection to the positive terminal. In the same way, change the black negative terminal.
  • To keep the battery bracket in place, replace it and tighten the screws clockwise.

Precaution to Take When Handling a Battery

  • When recharging a battery, do not use tap water. The battery will be harmed by the minerals in the water.
  • When the battery is charged or the mower is operated in the presence of water, an electric shock might occur, resulting in personal injury or death. So be very cautious. 
Removing and installing new battery in lawn mower

How Many Years Does a Lawn Mower Battery Last?

A riding lawn mower’s battery should last roughly for at least four years. When the battery reaches the end of its lifespan, you’ll notice that it doesn’t keep charging as before. 

How Do You Store a Lawn Tractor Battery in Winters?

  • Hook up a battery charger. Using a battery tender is probably the simplest way to keep your Lawn Mower battery in good shape.
  • Remove the battery and store it somewhere indoors.
  • Make sure your Mower is properly turned off.


Lawn mowers depend on batteries, therefore learning how to change the battery correctly will save you time and money. Do not be concerned if your mower battery indicates a change.

To replace your old mower battery with a new one, simply follow this article.

Also, make sure you purchase the proper battery for your lawn mower’s model and kind. Batteries aren’t all made equal.

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.