Lawn mower overheating is an issue often neglected by users because after cooling it down, you may proceed with another round of mowing. It may be caused by the engine itself or even the mowing deck etc. and will be solved mostly by maintenance.

Lawn Mower Overheating

Note that continuing to use it can lead to more damage, if not the total destruction of your lawn mower, especially its engine.

Overheating problems can be addressed even if you’re not an expert mechanic. Just by reading the manuals and this article, you could solve the problem right away. So keep reading on to find out more about lawn mower overheating.

What Reasons Cause Lawn Mowers Overheating?

The reasons that cause mowers overheating are many – among them are clogged engine parts and incorrect amount and use of oil. But, before knowing what causes lawn mower overheating, first identify what type of mower you have. For a start, is it the riding mower or the walk-behind type?

Lawn mower overheating is really a problem that is experienced by almost all lawn mower owners. In order to fix it, you need to know its causes first.

– Clogged Engine Parts

Dirty and clogged lawn mower engine parts are a common cause of mower overheating. This happens because the air cannot flow freely (in air filters, too) because of the blockage caused by debris and filth from previous mowing works. Easily clogged parts include the lawn mower cooling fins, cutting decks, and air vents of the mower engine.

– Cooling Fins Are Blocked

The cooling fins are those small plastic (or metal) materials near the spark plug. Through their movement, hot air dissipates from the engine. These generally get dirty very quickly and have to be cleaned regularly.

– Muffler is Not Working Correctly


The muffler removes the hot exhaust gases in the mower. If it is dirty it will not be able to do so properly and the outflow will decrease. When this happens the lawn mower may overheat and stall. It can be cleaned with a water and a brush. If they get too dirty you will have replace them.

– Incorrect Amount and Use of Oil

The mistake of using engine oil is not uncommon among mower owners. Engine oils aid in lessening friction between the moving parts of the engine. Having only a small amount of engine oil or not being able to reach the appropriate engine oil level would eventually result in engine overheating as friction increases.

Reasons Lawn Mower Overheating

Another engine oil mistake that could result in overheating is the use of unchanged oil. Oil becomes stale or bad when it is not changed regularly. It could also result in a thicker oil texture, which makes the engine parts work harder. Also, there are people who tend to pour (aware or unaware) the wrong kind of engine oil into their machine, which is a big mistake in the first place.

Engine oil comes in different varieties, depending on the engine type and the environment or the climate in which the machine is to be operated. SAE 30- is used in regions with warm temperatures.

Needless to say, you need to determine first what engine oil is appropriate for your mower. Negligence to do this could be the cause of walk-in or riding mower engine overheating.

– Can Blunt Blades Be to Blame for an Overheating Lawn Mower?

Yes, blunt blades can be to blame for an overheating lawn mower. When your blades are dull it causes a greater strain on the machine, therefore making it overheat. A sign to help look out for dull blades is that the grass seems to be torn rather than cut.

– Mower Deck is Full of Debris

Meanwhile, the cutting deck occupies the largest part of your mower as the blades are underneath this. When grass debris and other clippings accumulate in these parts, clogged air intake happens.

A mower deck full of debris will cause your engine to work harder and possibly overheat, just like with dull blades. The blades will start to get stuck and jam – but, the machine will just try to continue anyway and that will cause friction and overheating.

– A Loose Engine Guard

A loose engine guard can contribute to an overheating lawn mower. If the engine guard has come loose for whatever reason and it is not in its proper place you will not have the cool air kept around the engine as it should be. Overheating will ensue.

– Defective Engine Parts

Lawn mowers are among the most reliable pieces of equipment that you do not need to buy or replace often. With extra care, it could last for years. However, with long service, it is unavoidable that some parts would become defective. These defects may become the source of overheating in the machine.

A leaky gasket, a detached engine shield, broken fins, missing screws, and other minor defects that you may think of as inconsequential may, in the long run, interfere with the smooth operation of your lawn mower. Such defects could make the lawn mower overheat, or they could altogether stop the machine’s operations.

– Overworked Machine

Sometimes, a mower overheats simply because it has worked non-stop. Other reasons include being exposed to different weather elements, working on wet grasses and not making sure that the turf is dry first before starting the machine the next time, and cutting dense grasses not specified in their capacity.

These scenarios could also lead to the heating of the engine and, when not addressed, could result in overheating and, worse, is engine combustion.

How Do You Fix Overheating Lawn Mowers?

To fix overheating lawn mowers you must clean all the parts of the mower, replace or fix the defective parts, observe intervals during your mowing session, use the correct type of engine oil and maintain the correct engine oil level.

– Clean All Parts of the Lawn Mower

Practically, ensuring that your mower is clean is the first step in avoiding overheating. Free it from all the debris and dirt that congested all air filters and air vents. Knock off the stubborn dirt clinging to the insides of the machine.

Vacuum cleaners, sprayers, and even old toothbrushes can be used to reach out that deep-seated junk inside. Regular cleaning of the cooling fins and air filter will not only benefit the machine but also you and your yard in the long run.

– Replace or Fix the Defective Parts of Your Lawn Mower Engine

Whether it is a detached screw, a flapping engine shield, or cooling fins, they must be fixed immediately to avoid further trouble. Leaky gaskets of your carburetor could be replaced either by you or through the nearby shop. Replacing belts on your hover mower is also another way to minimize the risk of overheating.

– Observe Intervals During Your Mowing Session

Let the lawn mower have a break from a day’s work, and do not force it to cut wet grass. Letting the grass dry before mowing your lawn is a sure way to ensure that your mower will not be damaged. Also, let it cut grass according to its specification.

Solutions Lawn Mower Overheating

For your overgrown and dense yards, have the grasses cut twice or thrice so as to minimize the force exerted by the machine in doing the tasks. Adjusting the cutting deck to the appropriate level of the grass you want to cut would do the trick.

– Use the Correct Type of Engine Oil

The small engine of a lawn mower relies on oils to achieve maximum operation. Thus, feeding it with the correct oil type is an absolute requirement. Lawn mower overheating could really be minimized when following the necessary brand requisites.

– Maintain the Correct Engine Oil Level

See to it that the engine oil does not go below the minimum level required for the machine to function. Engines that are already low in oil are on deck for overheating, as friction and overworked parts would occur because of the lack of lubrication. Checking your oil level gauge regularly and keeping an extra stock will be a big convenience for you.

Frequently Asked Questions

– What Can I Do To Cool Down My Lawn Mower?

You can use air cooling to cool down your lawn mower. Turn it off first, and then cool your mower down by just letting it sit. See to it that no flammable materials can be found nearby. When it is cold, you can check for the cause of its overheating.

– How Long Does It Take for a Lawn Mower To Cool Down?

How long it takes for a lawn mower to cool down depends on a number of factors – the surroundings, particularly how airy it is and how much cover you were able to remove or detach from the mower before cooling it off.

– Can Water Be Used To Cool Down Overheated Lawn Mowers?

No, water isn’t recommended to cool down a lawn mower. The engine and all the metal parts could crack. It is better to allow overheated lawn mowers to cool down naturally by turning them off and leaving them alone in a well-ventilated area for at least 30 minutes.

– How Do You Know Your Lawn Mower is Overheating?

To know if your lawn mower is overheating you must observe certain signs. However, the first, and most obvious sign is that it simply cuts out. Other signs you may observe are smoking and you can physically feel the heat from the engine.

Why Lawn Mower Overheating


Small engines like that of your lawn mower could overheat due to various reasons. The ability to identify what causes the lawn mower to behave like this can help solve the problem.

  • A common cause of overheating among lawn mowers is grass cuttings, rubble, and other debris filling the engine.
  • These scraps are stuck in air intake manifolds and parts with air vents, thus preventing the smooth movement of air within the engine.
  • The use of bad or stale oil, wrong choice of engine oil, and inadequate oil level would also cause the overheating of the engine.
  • Overheating could be fixed by having regular checkups of the engine, using the correct amount and type of engine oil, and learning how much the lawn mower could work.

Lawn mowing is a satisfying activity as long as you don’t encounter any issues. Overheating of lawn mowers could be readily fixed if you know the cause, and act on it prudently to save more time and money.

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