How to Change a Lawn Mower Battery: Learn When and How to Change It

When my father had to change the lawn mower battery, we suddenly realized that it’s not so simple. 

We had to take professional help just to change the battery. Well, we weren’t planning to take help every time! So, I started to look for resources. I went to a garage as well. 

I found out that there are a few things people should be aware of. 

With a bit of help and research, now we can proudly change our lawn mower’s battery by ourselves!

Sharing these simple details might be helpful to a lot of you. 

I want you to change a lawn mower battery by yourself! Let’s get to know how to change a lawn mower battery.

6 Signs That Your Mower Needs a Battery Replacement

So, how do you understand that your lawn mower’s battery needs a replacement? 

You must be expecting some signs that your mower shows to indicate that it needs a battery replacement, right?

There are some signs of a low battery. 

1. Run Time Will Be Decreased

If your mower’s battery used to last longer between charges but now runs out quickly, it may indicate a declining battery capacity.

2. It Will Start Slowly

If the mower struggles to start or turns over slowly, even when the battery is fully charged, it’s a sign the battery is losing its ability to deliver power.

3. It Needs Frequent Recharging

When you find your mower needs to recharge the battery more often than before, it suggests diminished battery performance.

4. It Will Work Inconsistently

If the mower’s cutting power becomes inconsistent or stalls during operation, a weak battery could be the culprit.

5. There Will Be Visible Battery Damage

Inspect the battery for physical damage, leakage, or bloating. Any of these signs can indicate a faulty battery.

6. The Battery Is Aged

Batteries of the lawn mower usually have a limited lifespan. It is around 2-5 years depending on usage. If your battery is approaching or past its expected lifespan, consider a replacement.

So, if you notice these signs, you should replace the mower battery to ensure reliable and efficient performance.

Read: How to Use an Electric Lawn Mower: Learn in Easy Steps

What Are the Tools I’ll Need to Replace a Mower Battery?

As you know, you can replace your lawn mower’s battery at home, but you just need some tools for the task. Don’t worry; you don’t need a whole garage or many functional tools for that.

Here, I have listed the tools you should have right beside your hand while changing the mower battery. I have included the safety measures, as you can’t avoid them at any cost.

New Battery (Of Course)

First of all, you will need the right battery to change the old one. Just ensure you have the correct replacement battery for your specific mower model.

Safety Gear

While changing the battery, you have to wear appropriate safety gear, like gloves and safety glasses. 

These tools are essential to protect yourself during the replacement process.

Wrench or Screwdriver

To remove bolts or screws attaching to the batteries, you will need a wrench or screwdriver. 

You’ll need them again while securing the new battery compartment or cables.

Battery Terminal Cleaner

If the battery terminals are corroded, a terminal cleaner or wire brush can be useful to clean them before connecting the new battery. So, you should have them as well.

Battery Terminal Protectors

Applying a terminal protector spray or grease can help prevent future corrosion and ensure good electrical connections. 

So, if you have them at home, bring them as well.

Battery Charger

If you need to use a battery charger to fully charge the new battery before installation, make sure to follow the recommended guidelines.

Safety Blocks or Stands

To ensure safety during the replacement, you should use safety blocks or a mower stand so that you can lift and stabilize the mower while you work on it.

Mower User Manual

You should keep the mower’s user manual right beside you while replacing the battery. It will be an essential reference for the battery replacement procedure specific to your mower model. It will provide step-by-step instructions and safety guidelines.

Be Careful of the Safety Precautions

When you gather all the tools that you will need to change the mower battery, you can start, right? No, you can’t. 

There are some safety measures that you should be careful of right before you start.

Replacing a mower battery involves electrical components, and there can be potential hazards. So, it’s essential to take safety precautions. 

Here are some safety measures to follow when replacing a mower battery:

• Ensure the mower is completely powered off and the ignition key is removed to prevent accidental starts.
• Put on safety gloves and safety glasses to protect your hands and eyes from battery acid, debris, and electrical hazards.
• If you’re dealing with an older lead-acid battery, work in a space with good ventilation to disperse any fumes that may be produced.
• Remove rings, watches, and any metal jewelry that might come into contact with electrical components.
• If the mower has an electric start, disconnect the spark plug wire or any other power source to ensure there’s no electrical flow.
• Use the appropriate tools and equipment, as mentioned in the mower’s manual.
• If the old battery terminals are corroded, you will need to first clean them with a terminal cleaner or wire brush before connecting the new battery.
• Try to follow the manufacturer’s recommended procedures in the user manual to replace the mower battery.
• Be cautious when handling the battery cables to avoid creating a short circuit, which can cause sparks or electrical shock.
• While replacing an old battery, you should follow the local regulations so that you can prevent accidents from hazardous waste materials.
• If you disconnected the spark plug wire, reconnect it after you’ve finished replacing the battery.

I am warning you again, safety measures while replacing a mower battery are nothing you can forget about. Try to look again to see if the mower plug is connected and whether the mower power button is on. Also, don’t start working without wearing the safety measures.

How to Change the Mower Battery?

At this point, you must be aware of all the safety measures and have gathered all the tools to replace the battery, including the new battery. So, it’s time to replace the battery. Here are four easy steps you can follow to do it.

Step 1: Locate the Battery

First, you need to locate the existing battery. You can check the mower’s owner’s manual to identify the battery’s location. Most riding mowers have the battery under the seat, while push mowers may have it near the engine or handlebars.

Before you check the battery, just ensure the mower is powered off, and disconnect the spark plug wire for added safety.

Step 2: Remove the Old Battery

Now, you just need to remove the existing battery from the mower. But first, wear safety gloves and glasses to protect your hands and eyes.

Next, if your battery has a cover or terminal protector, remove it. You should use a wrench or screwdriver to disconnect the negative (black) cable first, followed by the positive (red) cable.

This order prevents accidental sparking. Well, carefully lift the old battery out of its compartment. Be mindful of its weight, as mower batteries can be heavy.

Step 3: Install the New Battery

At this point, you need to inspect the new battery to ensure it matches the specifications of the old one and fits in the compartment correctly. As it is matched, place it into the compartment.

Just ensure it’s oriented correctly which means positive to positive and negative to negative. Then, connect the positive (red) cable to the corresponding terminal on the new battery and tighten the nut securely.

Next to that, connect the negative (black) cable to the appropriate terminal on the battery and tighten the nut firmly. Ensure there’s a good electrical connection. If the battery has a cover or terminal protector, place it back in position.

Step 4: Test the Lawn Mower

In the earlier step, you have already installed the new one. 

Now, you need to test it. For that, reconnect the spark plug wire. Then, turn on the mower and check for any warning lights or indicators on the battery.

Now, attempt to start the engine. If you have an electric starter, make sure it cranks smoothly. Also, engage the blades or any other electrical components to verify that the battery is supplying power.

Take the mower for a short test drive to ensure it operates correctly. Monitor the battery voltage over the next few uses to ensure it holds a charge and doesn’t discharge too quickly.

How to Choose a New Replacement Battery?

Before you start, you will need a new battery to set up the mower. Now, there is confusion. 

Are you sure that your new battery is appropriate for the mower?

Listen, it’s very essential to choose the right mower battery. A wrong battery is both a waste of money and effort and it can destroy your mower as well. So, you need to ensure that you have chosen the right battery.

For that, you can follow the tips below.

Check the Mower’s Manual for the Battery Suggestion

The first step is to consult your mower’s manual. It typically provides information about the type and specifications of the battery your mower requires. Look for details like voltage, capacity (ampere-hours or Ah), and dimensions.

Find Which Battery Type Is Appropriate for the Mower

Mower batteries are generally available in two main types:

Lead-Acid Batteries: Commonly used in traditional gas-powered mowers, they come in two variants: flooded (wet-cell) and sealed (AGM or gel). Match the type to your mower’s specifications.

• Lithium-Ion Batteries: These are often found in cordless electric mowers. Ensure compatibility with your mower’s voltage requirements.
• Voltage and Capacity: Ensure the replacement battery has the same voltage rating as your original battery. The capacity (Ah) determines how long the battery can power your mower between charges. A higher capacity generally means longer runtime.

So, try to find out exactly which type of battery is suitable for the mower and then choose the right type.

Choose A Battery That Fit the Mower’s Physical Dimensions

Measure the space available in your mower’s battery compartment to make sure the replacement battery fits properly. Check the length, width, and height of the new battery against the dimensions provided in the manual.

Cranking Amps (CA) or Cold Cranking Amps (CCA)

If you have a riding mower with an electric starter, you should choose a cranking amp. A higher CA or CCA rating ensures sufficient power to start the engine.

Must Choose From a Reputed Brand and Quality

You should stick to reputable battery brands known for their quality and reliability. Reading customer reviews and seeking recommendations can help you choose a trusted brand.

Check the Maintenance Requirements

Decide whether you prefer a maintenance-free (sealed) battery or are willing to perform periodic maintenance tasks, like adding distilled water, for a flooded lead-acid battery.

What’s the Price?

You should also consider your budget but don’t forget to prioritize quality and compatibility. A cheaper battery may save money upfront but could lead to problems and replacement sooner than a higher-quality option.

Choose One with a Longer Warranty

Check the warranty and try to choose one that offers a longer time of warranty. It will be a reason for your peace of mind and indicate the manufacturer’s confidence in their product.

Besides, if your mower company sells dedicated batteries for specific mower models, you shouldn’t look forward to buying those batteries.

Maintenance Tips to Prolong the Life of the New Battery

I would like to share some pro tips to prolong the life of the new mower battery.

Just save the following tips in your head and utilize them occasionally for longer battery performance.

• Charge the battery before and after each use to prevent deep discharges.
• Periodically inspect and clean the battery terminals to prevent corrosion.
• If your mower is not in use for an extended period, use a battery maintainer or trickle charger to keep the battery charged.
• Store the mower in a cool, dry place to prevent excessive heat exposure.
• Don’t overload your mower with excessive tasks, as this can strain the battery.
• Follow the manufacturer’s guidelines for maintenance and storage.
• When the battery nears the end of its lifespan, replace it to prevent damage to other electrical components.
• Periodically inspect the battery cables for tightness and security.
• To charge the battery, try to use the dedicated charger that comes with the battery to avoid overcharging or undercharging.

Also, when it’s time to replace the battery, make sure to dispose of the old one following the local regulations for hazardous waste materials.

Wrapping Up

Replacing a mower battery is not a difficult task if you have common technical knowledge. 

if you have no previous experience or don’t have any idea about the mower mechanism, you shouldn’t attempt to do it yourself.

Changing a mower battery doesn’t cost too much even if you hire a professional. Try not to force yourself to do it alone if you don’t even know what a mower battery looks like.

But if you have minimal knowledge of machines and batteries, there is no need to worry about it unless you don’t have all the tools needed to replace the battery. 

The task is easy and you just need to be careful of the safety measures.