Do lawn mowers have alternators?” is commonly asked by curious lawn mower owners who are trying to learn about their tools. The answer to this question is yes, your lawn mower has an alternator, but it depends on the kind of lawn mower you own.

Understanding Alternators in Lawn Mowers

In this complete guide, we will cover all the answers to your question and explain other things with regards to lawn mower alternators that you need to know.

Do Lawn Mowers Contain Alternators?

Not all lawn mowers contain alternators, and a riding lawn mower is the only type that has one. In contrast, walk-behind or push mowers do not have one and do not need one. Lawn mowers with a gas-powered engine along with a battery-powered electrical system have alternators.

Riding lawn mowers contain an electrical system, and this electrical system is connected to the gas engine. Meanwhile, powered lawn mowers depend only on their rechargeable batteries or combustion engines, so they do not require to have an alternator to give them added electrical energy.

Riding lawn mowers are powered by an engine, and every engine has alternators to help it in moving the lawn mower. The alternator’s job is to maintain the lawn mower battery at a constant level. Once you turn over the engine, the alternator is the one that is responsible for charging the battery, so without it, your lawn mower will easily lose its power.

– Lawn Mower Alternators Appearance

The appearance of the alternator will depend on what kind of lawn mower you have as there are different types. There are belt-driven alternators and stators, but generally, your lawn mower alternator is located underneath the engine cover or hood, together with other engine components.

Let’s talk about the two different types of charging systems that lawn mowers use.

Are Lawn Mowers Equipped with Alternators

If your mower has a belt-driven alternator, you can easily identify it by looking for a component that consists of a round aluminum housing with open ridges around it, along with a belt and pulley located at the center of its exterior.

Typically, you can find it in the engine compartment, which is fixed to the engine. Commonly you can see your alternator attached to the edge of the lawn mower engine and not on the top or bottom.

On the other hand, if the charging system of your lawn mower uses a stator, you need to look for a rounded metal that has a hole in the center, about one inch thick and four to five inches diameter. It will also have copper wire placed all the way around on its sides.

You will need to detach a few parts to get to its location. This charging system is located in the lawn mower engine compartment, and the stator is usually located underneath the flywheel.

If you need to gain access to the flywheel, you will have to remove different parts, such as the blower housing, air filter, and flywheel fan, and if you need to check or replace the stators, you will be required to remove the flywheel.

– How It Works

Alternators work by generating electricity. They use mechanical energy and convert it into electrical energy during the time that the engine is working. Commonly, a magnetic field is produced when a belt rotates the pulley that turns a rotor and spins it around a stator.

This magnetic field is harnessed by the stator and creates electricity using alternating current. Finally, this current will be divided among other components of the lawn mower like the battery, electrical parts, and the engine to execute functions.

– Purpose

The lawn mower alternator is one of the most significant parts of any riding lawn mower. The truth is, without it, your riding lawn mower cannot function. The alternator provides the electricity that the engine needs through spark plugs. If the spark plugs are not working, gas cannot be ignited and the engine won’t turn over.

Alternators in Lawn Mowers

This is also the reason why when your lawn mower is having a problem, chances are its alternator has a problem. Thus, fixing or replacing your alternator if it is already damaged will probably address the problem.

The function of the alternator is to charge the battery on a riding lawn mower. This enables many components, such as headlights, electric ignition, and clutches, to perform their functions. Push lawn mowers do not have alternators, but for riding lawn mowers without an alternator or charging system, their battery would drain easily.

– Overheating Alternator

It can be a challenge to test and identify when you have to fix your alternator. Given that riding lawn mowers have a lot of ground to cover than walk-behind mowers, one of their common problems is overheating as they need an ample amount of energy when compared to mowers that do not have alternators.

Especially for areas with rough terrain, you should use specific riding lawn mowers. To avoid this kind of problem, you have to keep in mind that your lawn mower alternator must be under the right temperature.

Overheating causes damage not only to your alternator but to other inner parts as well. Also, do not forget that this is the most expensive part of a lawn mower. So, as you go through your mowing session, allow a period of time for your mower to cool down before doing the process again.

Instead of going for a single cutting process, divide it into shorter sessions wherein the temperature of your lawn mower will stay within the acceptable range. This will ensure your lawn mower remains in top condition. Overheating can harm other parts as well, which means that you figure out what caused the lawn mower to overheat and how to fix it.

– Testing the Alternator

There are two effective methods by which you can test whether your mower’s alternator is in good working condition. First is by switching on the headlights and shutting down the engine of the mower.

If you observe that its lights become faint when you shut down the engine, then your mower’s alternator is working. However, if you notice that the lights remain the same even when you turn over the engine, it means that the alternator is having a problem.

Importance of Alternators in Lawn Mowers

Another way to test your alternator is by using a multimeter. A multimeter is a measuring instrument that is used to measure electrical properties. Choose the kind of multimeter depending on the type of alternator that your lawn mower is using.

Attach a multimeter to your mower’s engine, turn over the engine, let it operate for a while, and then inspect the readings. If the results are much lower than those written in your lawn mower’s manual, then this can be interpreted as there being something wrong with your alternator.

Another thing you need to look out for would be the connecting cables. There are times when the cables that are connecting to the battery are loose. This causes the battery to be strained, causing it to work harder than it has to, which may be the reason why your battery releases power faster.

Aside from checking the alternator, see to it that you inspect the cables as well, make sure that they are tightly attached and well cleaned. Doing this will improve your battery’s ability to retain power. Now, if you have done the steps that we have mentioned above and your alternator is still having recurring problems, then this may be the right time to replace it with a brand new one.


Your riding lawn mower has an alternator that keeps it running by charging its battery.

Here are some essential factors to remember about your alternator:

  • Not all lawn mowers have alternators. Riding lawn mowers are the only type of lawn mower that has an alternator.
  • An alternator can be a belt-driven alternator or a stator.
  • The alternator is the one that is responsible for running your lawn mower.
  • The alternator is the most expensive part of your mower, so take good care of it.
  • Avoid problems like overheating by allowing your lawn mower to rest in between cutting sessions.

The alternator is a very important part of your lawn mower that requires care and maintenance, so knowing if your lawn mower has it and the other details related to it is an important thing that can be beneficial to you and to your lawn mower.

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