Riding mower battery voltage. Charging a battery in a riding lawn mower video

Charging a battery in a riding lawn mower video

You may need to charge the battery in your riding lawn mower at the start of the mowing season, or if you accidentally drained your battery by leaving the ignition on. Either way, this video shows you how to charge your battery safely using a charger.

For additional repair help, including common symptoms and troubleshooting tips, step-by-step riding lawn mower and tractor repair guides and articles, check out our repair help section. In addition, find the riding mower parts you need to fix your mower.

Supplies you may need

Hi, Wayne here from Sears PartsDirect. Today we’re going to talk about how to charge the battery in a riding mower. You may need to charge the battery before starting your mower for the first time in spring. And you should fully charge your battery before storing your mower for the winter.

Of course, you also need to charge the battery if it’s unexpectedly dead—perhaps because you left the ignition switch on and drained the battery.

Find the correct charger for your battery

Most riding mowers use 12-volt batteries, but some models built before 1980 use a 6-volt battery. Use a charger that matches the voltage for your battery. Also, use a charger with an output of 10 amps or less. Charging a battery with more than 10 amps can damage it. You can charge the battery without removing it from the mower. Wear work gloves and eye protection when charging your battery.

How to connect charger cables to battery

First, unplug the battery charger from the outlet. Lift the seat and connect the red charger cable to the red, positive battery terminal. Connect the black charger cable to the black, negative battery terminal. Set the battery charger to 12 volts and 10 amps or less. Plug in the charger.

The charger should fully charge the battery in one hour at the 10-amp setting. You might have to charge the battery longer if your amp setting is lower. Some chargers shut off automatically when the battery reaches a full charge. Unplug the charger once it indicates the battery is fully charged. Disconnect the charger cables from the battery and lower the seat.

There you have it—a fully charged battery, ready for use or storage. I hope this video helped you out today. Be sure to check out our other videos here on the Sears Parts Direct YouTube channel. Subscribe and we’ll let you know when we post new videos.

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Unlike traditional gas mowers, Greenworks electric mowers require no gas or oil changes, spark plug replacements, or carburetor cleanings. This makes maintenance a breeze, our mowers only need occasional blade sharpening and cleaning (discharge, bag, etc.) to keep them running smoothly.

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Lawn Mower Battery Size Chart | A Comprehensive Guide On Lawn Mower Batteries

Mowing is a fancy word for cutting grass. As a part of maintaining the lawn, many of us spend the maximum time mowing the lawn. The purpose of mowing is to keep the grass in the lawn at a set height so that the lawn looks neat and attractive. Lawn Mowers, as the name suggests, are a piece of special equipment that helps us in mowing lawns. Today, we have cordless and electric type lawn mowers that mow using an electric motor. But if you need a heavy-duty lawn mower, then chances are you look at a gas-powered lawn mower. Earlier gas-powered lawn mowers use a pull-string to start the engine. But nowadays, you get simple electric start models. The problem with electric start lawn mowers is they need starting batteries and depending on your usage, they die and you have to replace them.

There are several important parameters and specifications that you need to be aware of while choosing a replacement. So, in this guide, we decided to make a beginner’s guide on Lawn Mower Batteries. First, we will all the essential things about lawn mower batteries and then we will move to the lawn mower battery size chart.

Using this chart, you can compare your battery with the specifications of other batteries and purchase a perfect replacement.

A Brief Note on Lawn Mowers

We have been using lawnmowers since the late 1800s. All the initial lawnmowers were completely mechanical devices. Very soon, we saw gasoline-engine-based lawnmowers that made the job of lowing a garden very fast and easy.

These types of mowers are very popular even today as they are very powerful and allow you to mow thick and tall grass very easily. Then we have the main electric-powered lawn mowers.

They are small and easy to maneuver in small to medium-sized gardens. As a result, they became very popular in the market. But the limitation is you need to drag the cable or you can reach as far as the cable allows you.

The next important type is also electric but this time it is in the form of battery-powered mowers. These are cordless devices and you can use them anywhere you want. Their ridiculous cost makes them a niche product.

Types of Lawn Mowers

The basic type of lawn mower is a Reel Mower. It is a mechanical device that runs on our muscle power. We have to push the mower and when the wheels rotate, blades mounted on a cylinder cut the grass with a scissor-like action.

Next, we have rotary mowers that are powered by electricity, a battery, or a gas engine. Of the three power sources, gas-powered rotary lawn mowers are very common and popular, especially in the North American market.

You get both push-type as well as self-propelled models in gas-powered mowers. These types of mowers are very useful for large gardens, usually up to half an acre.

If you have a relatively small lawn, then corded electric lawn mowers are ideal. They are silent (comparatively), do not pollute, and are easy to maintain. Maneuverability is the main concern with corded-electric lawn mowers. In most cases, you have to stay within 150 to 200 feet distance from an electrical outlet.

An alternative to this is battery-powered cordless electric lawn mowers. They are very easy to maneuver as you don’t have to worry about the electric cord. Cordless Lawn Mowers are heavier than their corded counterparts.

Depending on the size of the battery, these models allow you to mow continuously anywhere between 45 minutes to 2 hours. But the cost of cordless lawnmowers is very high.

All the models we discussed till now are push-type or walk-behind mowers. But there is another type in the form of ride-on or riding mowers. As the name suggests, you can sit on the mower and ride it across the lawn to mow the grass.

If you have a very large lawn, over half an acre, then it makes sense to invest in a riding lawn mower. Usually, the ride-on mowers are gas-powered with rotary-type cutting mechanisms.

You often hear the term lawn tractor when you browse for riding lawnmowers. While ride-on lawn mowers just mow the lawn, riding lawn tractors can mow the grass and much more.

With the correct attachment, you can use a lawn tractor for mowing, dethatching, aerating, fertilizing, and even plowing snow.

Understanding Lawn Mower Batteries

As we mentioned in the previous section, gas-powered lawn mowers are very popular, be it the walk-behind type or the ride-on type. Earlier models came with a pull-string to start the gasoline engine.

Depending on the age of the mower, you could start the engine with a single pull in case of a relatively new and well-maintained mower. But as it ages, the performance of this starting mechanism starts to fail and you might need to pull more than a couple of times to crank the engine.

This is where lawn mowers with starter batteries come in handy. These batteries work similarly to our car SLI batteries as they help crank the gasoline engine of the mower.

With the push of a button or twist of a key, you can start the lawn mower and don’t have to worry about any pull strings.

Comparison between Lawn Mower Batteries and Car Batteries

The moment we say lawn mower batteries are useful for easily starting the mower’s engine, we immediately start comparing them with car starter batteries. They are similar in some aspects but there are a lot of differences as well.

Let us begin with the similarities. Car batteries are usually flooded lead-acid type or sometimes maintenance-free gel-type. It is very rare to see other types of batteries as car starter batteries.

Even lawn mower batteries are lead-acid batteries and they come in both flooded as well as gel types. But surprisingly, you can also find lithium batteries for lawn mowers.

As the majority of batteries in both cases are of type lead-acid, their working remains more or less the same. The advantages and problems you have with car batteries, you also have them with lawn mower batteries.

This includes low cost, a simple charging system, the life of the battery, etc.

Does this mean can we use a car battery in a lawn mower? No. this is where the differences kick in. First thing, car batteries are much bigger than lawn mower batteries, both in terms of physical dimensions as well as capacity.

The main difference is the starting current they can provide, which we usually represent as Cold Cranking Amps or CCA. As car engines are quite large, their batteries must provide a lot of amps to crank the engine.

So, you usually see CCA ratings of 500A or more in car batteries. But lawn mower engines are small. You don’t need such large currents. That’s why you will see CCA ratings in mower batteries in the range of 130 to 150A.

Important Specifications of Lawn Mower Batteries

Continuing the previous section’s discussion, let us see some important parameters and specifications of typical lawn mower batteries.

Type of Battery

As we mentioned before, you can find both lead-acid and lithium batteries for lawn mowers. In the case of lead-acid type, you again have flooded, AGM (Absorbent Glass Mat), and Gel types. Each type has its advantages and disadvantages.

Lithium batteries or Lithium Iron Phosphate to be specific, are also becoming quite popular with lawnmowers. The charging and protection methods (or lack thereof) are very different between lead-acid and lithium batteries.

Lead acid batteries are affordable, heavy, and robust to operate in all climatic conditions. But the problem is you have to take care of them and make sure they are fully charged all the time. Speaking of charging, the number of times you can charge and discharge a lead-acid battery is very less.

Lithium Batteries on the other hand are expensive and lightweight. Even though they support a good number of charge/discharge cycles, they need special circuitry in the form of a Battery Management System or BMS to protect the individual lithium cells from overcharging, deep discharging, etc.

Charging lead-acid and lithium batteries is very different. You can get chargers that support both these battery types but double-check the capabilities of the charger before using. Do not blindly use one type of charger on the other type of battery.

If the lawn mower has an alternator (which is usually the case with riding-type lawn mowers and lawn tractors), it can charge the battery once the engine is on. But for smaller mowers, this is usually not the case. You have to charge the battery externally.

Size and Other Physical Parameters

Physically, lawn mower batteries are smaller. In the next section Lawn Mower Battery Size Chart, we will see the dimensions of some popular types of lawn mower batteries.

Another important “physical” aspect of lawn mower batteries is the terminals and their position. Unlike car batteries, which usually have a pretty standard type of terminals, mower batteries have more than one type of terminal to connect the cables.

Also, the position of the terminals might be different between brands, manufacturers, and battery types. Usually, in a particular battery group, the type of terminals and their position (which is almost always on the top) will be common.

But we cannot say the same when you go to a different battery group.


The reason why we are talking about battery voltage is in the early days of lawn mower batteries, we used to get them in 6V ratings as well. But it is safe to assume that most modern mower batteries that we get today are 12V batteries.

This applies to both lead-acid and lithium batteries. So, all the batteries we are going to discuss in the guide are 12V unless otherwise mentioned.


The capacity of a starter battery is an interesting specification. It represents the amount of current in amps a fully-charged battery can deliver for 10 hours straight.

We usually see the battery capacity specification as Ampere Hour or Ah. Depending on the size of the battery, its capacity can range anywhere between 10Ah to 40Ah.

Cold Crank Amps (CCA)

This is one of the important specifications of a starter battery, be it for cars or lawn mowers. What does CCA mean? Cold Crank Amps or CCA represents the amount of cranking current (in amps) a fully-charged battery can deliver for a period of 30 seconds at a temperature of 0°F.

As the size of the gas engine in mowers is small, you don’t need a large cranking current to start the engine. Hence, you will see CCA ratings of mower batteries in the range of 100A to 300A. You can find batteries with CCA ratings more or less than this range. You have to check your lawn mower’s manual as it will usually recommend a specific CCA value.

Lawn Mower Battery Size Chart

An important thing to remember before purchasing a new mower battery is they are significantly smaller than car batteries and within lawn mower batteries we have several sizes.

A Battery Group categorizes the physical dimensions of the battery. All the batteries falling in a particular group have nearly identical shapes and sizes. If you are familiar with car and boat batteries, there are we have several battery groups.

Let us now see some popular lawn mower battery groups. The groups in this list are no way near the full possible types but these are pretty common with mowers.

The following table is a Lawn Mower Battery Size Chart consisting of the common battery groups.

Battery Group Length (inches) Width (inches) Height (inches) Voltage
U1 7.75 5.1875 7.3125 12V
YTX30L-BS 6.5625 4.9375 6.8750 12V
U1R 7.75 5.1875 7.3125 12V
YTX24HL-BS 8.0625 3.4375 6.375 12V
21 8.19 6.81 8.75 12V
YTX20L-BS 6.875 3.4375 6.375 12V
22F 9.5 6.875 7.3125 12V
YTX14-BS 5.875 3.4375 5.75 12V
22NF 9.4375 5.5 7.1875 12V
YTX12-BS 5.875 3.5 5.125 12V
24 10.25 6.81 8.87 12V
YTX9-BS 5.875 3.4375 4.125 12V
27 12.06 6.81 8.75 12V
YTX5L-BS 4.4375 2.75 4.125 12V
30H 13.5 6.81 9.25 12V
31 13 6.72 9.44 12V
45 9.4375 5.5 8.75 12V
70 9.0625 7.0375 7.8125 12V
4D 20.75 8.75 9.88 12V
8D 20.62 10.95 10.17 12V

Different manufacturers have their own set of battery sizes and they may or may not be compatible with batteries from other manufacturers. But if they come under the same battery group, then chances are they will become compatible.

How To Choose a Replacement Lawn Mower Battery?

The common thing between a gas-powered lawn mower and a car is they both have engines. But we take cars very frequently to school, work, shopping, or other commuting activities.

This is not the case with lawn mowers. We use them only when we need to mow the lawn or garden. So, for the most part of its life, a lawn mower usually sits in a garage or shed.

Here comes the problem. As we take our cars out for a spin on a regular basis, the level of discharge of the car’s starter battery won’t be that bad. But as lawn mowers are sitting idle most of the time, there is a good chance that the battery will discharge pretty quickly.

If you have an external charger, then you can extend the life of the lawn mower battery. But in case you don’t have a battery charger, then you will at a replacement in a short time.

Things to Consider for Lawn Mower Battery Replacement

The first and most important thing while choosing a new lawn mower battery is to check the physical dimensions of the battery. Lawn Mowers have a slot for the battery that fits only one type of battery.

When we say one type, we mean one size. The replacement battery must fit perfectly into that slot and it should be loose (and if it is tight, you can’t even fit the battery into the slot).

So, check the owner’s manual or maintenance guide of your lawn mower and look for battery specifications. If they mention the battery group, then you can simply browse for that particular group and purchase a replacement.

What if you can’t find the battery group information? We have to old school and measure the dimensions of your current battery. With this information, you can look up any lawn mower battery size chart and compare the dimensions with the common and popular battery groups in the list.

After the battery group size, the next important specification is the CCA rating of the battery. Once again, check the user manual if they specify the necessary CCA of the battery. If not, look at the label of the current battery and you might find the CCA ratings.

When shopping, you need to match the CCA values. It can be higher than the current value, but never lower. But if you opt for a higher CCA rating, then you have to spend more money.

Troy-Bilt TB30R. Battery Not Charging

Another important thing is the type of battery. We have lead acid and Lithium Iron Phosphate as the two base battery types. Further, in lead-acid, we have wet or flooded, AGM, and Gel types.

Always choose a replacement battery of the same type as your current battery. The compatibility between different battery types is, to put it in simple terms, highly questionable.


If you have a lawn or garden, then you have to invest in a decent lawn mower. It does the job of shearing or cutting the grass and maintaining it at a set level very easily.

Like many power tools, even lawnmowers come in different shapes, sizes, and power options. The most common and popular one is the gasoline engine-powered lawn mower.

Pull-starting the gas engine of the lawn mower is an old technique. Nowadays, most lawn mowers come with electric starters. When we say electric starters, it means there is a battery involved in it.

If the battery is old or dead beyond recharging capabilities, then you have to look for a replacement.

In this guide, we saw the basics of lawnmowers and their types. Then we moved to different types of lawn mower batteries and also some important specifications you need to consider while looking at mower batteries.

After that, we made a simple lawn mower battery size chart. This chart consists of some popular lawn mower battery groups with their physical dimensions.

We hope that this guide on lawn mower battery size chart could help you understand the basics of lawn mower batteries and also in making an easy purchase decision.

If you feel we missed something or want us to add anything, do let us know in the Комментарии и мнения владельцев section below. If you want, we can add lists of possible replacements in several battery groups (for instance, all the best replacement batteries for the U1 or U1R battery group).

Symptoms of a Bad Lawn Mower Battery: Hard To Miss Signs

If you are curious about the symptoms of a bad lawn mower battery, the nyou are among the thousands of gardeners who have this question in their minds. The good news is that most symptoms are hard to miss, such as clicking noises and rotten eggs smell.

In this complete guide, we will discuss all the symptoms that indicate that your battery might be struggling. Carry on reading because we will also discuss changing the electrolyte fluid in the battery to make it last longer.

  • What Are the Symptoms of Your Lawn Mower Battery Going Bad?
  • – The Engine Won’t Start
  • – Produces Clicking Sounds
  • – Produces a Rotten Smell After Some Use
  • – The Battery Loses Charge Quickly
  • – The Mower Refuses To Cut Grass
  • – The Battery Appears to Bulge
  • – Poor Fluid Levels
  • 1. Assess the Condition of Your Battery
  • 2. Conduct a Voltage Test
  • 3. Prepare the Tools You Need
  • 4. Remove the Battery First
  • 5. Clean the Battery
  • 6. Fill the Battery With Fresh Electrolytes
  • 7. Recharge the Battery
  • 8. Check the Connections

What Are the Symptoms of Your Lawn Mower Battery Going Bad?

The symptoms of your lawn mower battery going bad include the engine not starting, the mower producing clicking noises and a rotten egg smell, the battery losing charge faster than normal, the mower refusing to cut grass, and poor fluid levels.

It is easy to tell if your lawn mower’s battery has gone bad. Some classic tell-tale signs of such a battery are that the engine won’t start, produce clicking noises and produce toxic fumes.

riding, mower, battery, voltage

– The Engine Won’t Start

The first tangible sign of a bad battery is when the mower won’t start on the first pull. Even more, multiple ignition turns might be needed to get the engine fired as the situation worsens. This means the engine does not have adequate strength to fire the spark plug.

After multiple tries, it does so feebly when the engine fires up. It will crank much more slowly than normal, sometimes not at all. However, the engine not starting can also be due to a faulty spark plug, ignition button, or alternator. Make sure to check these out to see that they are working properly before moving on to the battery.

– Produces Clicking Sounds

A lawn mower is not supposed to make unnecessary sounds while working, so if it starts producing clicking sounds when you attempt to turn it on, the battery is running low on power. Recharging it properly might solve the problem.

riding, mower, battery, voltage

Sometimes, the mower produces clicking noises and starts but does not turn over. This might mean that the battery is completely dead and in need of a replacement. When the lawnmower battery gets bad because of freezing and extreme weather conditions, this could cause problems with clicking and the engine starting without turning over.

– Produces a Rotten Smell After Some Use

A bad battery gets heated soon after use and produces toxic fumes. This is more pertinent for lead-acid batteries, where the sulfuric acid in the electrolyte gets turned into toxic fumes once the battery heats up.

In most of these cases, you will be able to smell hydrogen sulfide immediately because of its rotten egg smell. Be careful when touching the mower where the battery is located as it will be quite hot. Turn the engine off and let the mower cool down before doing anything else.

– The Battery Loses Charge Quickly

A lawn mower battery that either does not charge fully or stays charged afterward is going bad. Either the battery is too old or damaged, or there is something wrong with the charger.

With time, the battery’s capacity to hold charge does decrease naturally. After some years, you might notice having to charge it more often than before. However, if the battery is new or seems to be losing charge abnormally fast, then this is problematic.

If the battery refuses to charge altogether, in this case, your charger is faulty or the battery has gone bad.

– The Mower Refuses To Cut Grass

One uncommon and often ignored symptom of a gas-powered lawn mower’s battery going bad is that it will no longer be as efficient as before. It might work fine on thin, wispy grass, but as soon as you try to cut tall, thick grass, it will give up.

The battery is not strong enough to provide the engine with the power to cut through resistance. Check your blades to ensure there is nothing wrong with them, like a need for further sharpening. If they are okay, the battery is going bad and you need to fix it.

– The Battery Appears to Bulge

In riding mowers, the battery is usually located under the seating area and charged without taking it out of its box. That is why people often need to pay more attention to this vital symptom that the battery could be better.

When the engine stops turning off or producing clicking noises, take the mower’s seat off and take the battery out. It would help if you unscrewed some nuts and bolts here and there to loosen it. Notice the classic signs of battery wear down on all sides, including the bottom.

Jump Starting a Riding Lawn Mower

These signs include cracked edges, bulging sides, and blue-green corrosion on each battery terminal. Have a mechanic look carefully at this battery in case it becomes a health hazard.

– Poor Fluid Levels

Fluid levels within the battery are important indicators of a healthy vs. bad lawn mower battery. Check the fluid levels within each cell of the battery for this. In the case of lead-acid batteries, the electrolytes are a mixture of water and sulfuric acid.

Many things disturb the delicate balance of fluids within the electrolyte, such as overuse, overcharging, physical damage, or a battery that is too old. If the fluid levels within the battery are low, it is in an apt condition.

If the rest of the battery is in good condition, restoring the fluid levels will improve the battery. Buy a couple of bottles of distilled water and use them to get your battery working again.

How Do You Improve a Bad Lawn Mower Battery?

To improve a bad lawn mower battery, you should first assess the condition of the battery and conduct a voltage test. Prepare the tools that you will need and carefully remove the battery. Next, clean the battery and fill it with fresh electrolyte.

Unless the battery is completely dead, you can help improve its condition by cleaning it and changing its electrolyte fluid. Instead of buying expensive fluid from the market each time, make your electrolyte at home using Epsom salt and distilled water.

Assess the Condition of Your Battery

Before deciding whether to change or repair the battery, assess it thoroughly. First, ensure that each cell is filled with the electrolyte until the line.

Then give the battery a detailed examination to see if it is corroded, cracked, leaking, or bulging from anywhere. If any of these symptoms are present, then it is better to discard them for a new one.

Conduct a Voltage Test

A voltage test will determine whether or not the lawn mower’s battery is dead. Most lawn tractors and lawnmowers use a 12-Volt battery to run them. A fully-healthy 12-Volt battery, when fully charged, will display a voltage of around 12.6 to 12.8 Volts.

In case of an older mower with a six-volt or lower battery will also display a voltage of six volts when it is completely charged. You will need a multimeter to check this voltage. If there isn’t one present at home, borrow it from someone or order one online as they are pretty cheap.

Attach the multimeter to the battery and set it at DC at 13 volts. The meter’s red lead should be attached to the battery’s positive terminal, while the black lead goes to the negative terminal. The battery has gone bad if the meter reads less than 12.3 volts. If the voltage comes out fine, then proceed to the next step.

Prepare the Tools You Need

Use your safety goggles, full-sleeved clothing, and thick rubber gloves when dealing with the lawn mower engine and battery. Make sure your battery charger is functional, automatic, and has an in-built voltage regulator.

Find baking soda and distilled water at home or in your local supermarket. A plastic funnel is also a must-have item. Epsom salt (magnesium sulfate) is the last ingredient you will need.

Remove the Battery First

Turn the engine off, pull out the keys, and disconnect the spark plug. Around 90 percent of riding-style mowers have batteries under the driver’s seat. Pull up the seat, loosen the screws holding the battery in its chamber, and carefully pull it out.

For any other type of mower, consult the instructions manual to see where the battery is located. Disrupt the negative and positive terminals to remove the battery from its chamber first.

There will be caps on each battery cell which need to be removed. Usually, they will be located right on top of the battery and easily come off. Otherwise, a small flathead screwdriver will help you uncap the battery.

Clean the Battery

If the battery terminals have bluish-green corrosion, clean them first. A corrosion-cleaning solution with sandpaper will help clean the discoloration. The next step is to drain out all the existing fluid from the battery.

The insides of the battery need to be cleaned from sulfate buildup over the years. Measure 10 ounces of baking soda and dissolve it in one whole gallon of distilled water. Using the funnel, pour this solution into the empty cells of the battery and put their caps back on.

Now shake your battery thoroughly and leave it for a minute or two, then drain the solution out using the same funnel. Make sure you wear the thickest rubber gloves you have because these solutions can burn the skin.

Fill the Battery With Fresh Electrolytes

Now that it is clean, your battery needs fresh, new electrolytes added to it. You can buy electrolytes premade or make it yourself at home. It is simple, and you only need to add 15 ounces of Epsom salt to one gallon of distilled water.

Warm the water a little bit first, so the salt dissolves quickly. Again, the funnel will be helpful while pouring the electrolyte into each battery cell. There is a line on each cell until you fill it. Be mindful that you don’t overfill or underfill the battery. Screw the caps back on each cell, and your battery is ready.

Recharge the Battery

Next, it’s time to recharge your newly filled battery for the first time. Always use automatic chargers with adjustable settings options for charging.

Set the charger to the slowest charging option, around two amperes per 24 hours. Yes, it would help if you gave the battery at least one whole day to become charged. During this time, keep the caps on individual cells slightly loose for any potential outflow of the charge.

Once the battery is charged to 100 percent, tighten the cell caps. Carefully place the battery back in its place within the mower. Attach the positive terminal and then the negative one when connecting the battery to the mower.

Check the Connections

Before restarting your newly charged battery again, check that all its connections with the engine are correct and secure. The negative and positive terminals should be attached properly to their required connections. If broken or damaged, the cables will not let the engine start, so it is better to replace them.


Before we conclude this article, here are the most pertinent points regarding a bad mower battery.

  • The first sign of a bad battery in the mower is that the engine will have a harder time starting and producing sounds while working.
  • Bad batteries lose charge rapidly and need frequent recharging. They also produce toxic gases and fumes, such as hydrogen sulfide, that smell like rotten eggs.
  • A bulging, cracked, or leaking battery is also symptomatic and needs to be replaced immediately.
  • If the battery is not dead, then take it out, clean it, and replace its electrolyte with a fresh one.

When the mower battery gets old, you must be careful about potential symptoms if it doesn’t work as well as before. This would ensure that you improve its condition or change it before it becomes a potential health hazard.