You expect your lawn mower to move forward and cut grass with precision when the blades are engaged. But when a mower bogs down, the blades stop spinning as quickly, which puts strain on the engine. The engine can overheat and seize up, causing permanent failure. In some cases, the blade can also malfunction.

A bogging mower is an indication that something is wrong. It may be caused by dull blades, a build-up of grass clippings, or a dirty air filter. If the air filter is clogged, it can restrict airflow and cause the engine to run less efficiently.

It is necessary to troubleshoot the situation to resolve it. The following article will provide information regarding the possible causes of a mower bogging down and what you can do to resolve the issue.

Symptoms of a Bogging Mower When Blades Engage

Symptoms of a Bogging Mower When Blades Engage

When you engage the blades on your lawn mower, you expect the engine to speed up as it kicks into high gear. Then again, the opposite may occur, and the engine may bog down. Several symptoms may be associated with a bogging mower:

  • The engine RPMs decrease during blade engagement
  • The engine makes a choking sound
  • Smoke starts coming from the engine
  • The engine begins to overheat
  • Grass accumulates under the mower deck quickly
  • The mower leaves streaks of uncut grass

If you notice either of these symptoms, it’s essential to take your mower to a mechanic to have it checked out. Otherwise, you may end up doing more damage to your mower than necessary.

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Why Does My Mower Bog Down When I Engage the Blades : Reasons

Bogging down a mower can happen when the grass is too thick, or there is too much debris in the way. It can also occur if the mower’s blade becomes dull. Bogging down causes the mower to slow down and can even stop it from moving altogether.

This can be annoying for the person trying to mow their lawn and damage the mower. The followings are the most common reasons for a mower bogging down:

Dirty Moving Parts

Dirty or clogged moving parts commonly cause lawn mowers to bog down. The lawn mower’s blades need to move freely to chop the grass. If the blades, wheels, and other moving parts of the riding mower become clogged with dirt or twigs, they will not move as quickly, bogging down the mower.

Also, dirt and debris can prevent the engine from getting the proper amount of air, causing it to overheat. As a preventative measure, keep the moving parts of your mower clean. Periodically remove any build-up twigs and debris, and make sure that the engine has plenty of airflows.

Faulty Spark Plug

The lawn mower’s engine relies on a spark plug to ignite the fuel. It is responsible for igniting the fuel in the engine, and if it isn’t working properly, the engine can’t run correctly. This can cause the mower to bog down and eventually stall.

If you think your spark plug may be the problem, check it for any damage or debris causing it to malfunction. You may also need to change the spark plug if it is old or worn out. Regardless of the cause, getting your mower back up and running doesn’t have to be a hassle.

Clogged Air Filters

Clogged air filters are a common problem when mowing lawns. The air filter is responsible for keeping the engine clean and running smoothly. The engine of a lawn mower can quickly overheat if an air filter is clogged. Grass and twigs can build up in the filter, causing the engine to bog down.

This reduced airflow can also lead to several problems, including a loss of power and decreased fuel efficiency. In some cases, it can even lead to the engine failing. For these reasons, it’s essential to regularly clean or replace the air filter in your lawn mower.

Another possible cause of a clogged air filter is a leaky gasket. A gasket helps to seal the engine and keep contaminants out. But, as time passes, the gasket can degrade, allowing dirt and debris to enter the engine. In turn, this can cause the air filter to become clogged and eventually lead to engine bogging.

Dirty or Dull Blades

When lawn mower blades become dull or dirty, bogging can occur. Dull blades tear at the grass rather than cutting it cleanly, which puts stress on the engine and makes it harder for the mower to move.

Also, build-up debris can be on the blades, making them less effective at cutting grass. As a result, it’s essential to keep an eye on the condition of your lawn mower’s blades and sharpen or clean them as needed.

Dirty Carburetor

The carburetor is intended for mixing fuel and air in the correct proportions, and a build-up of dirt and grime can prevent the carburetor from working correctly. As a result, the engine may run lean, leading to poor performance and increased fuel consumption.

In some cases, a dirty carburetor can also result in the engine stalling. If you notice that your lawn mower is bogging down or running poorly, check the carburetor and give it a good cleaning with a carburetor cleaner. Also, ensure that the carburetor receives the proper amount of air by checking the air filter and gasket.

Low Engine Oil Level

It is noteworthy to monitor the oil level in your lawn mower engine. If the oil level gets too low, your engine may bog down. The reason is that the oil helps lubricate the engine parts. When there is not enough oil, the parts can start to rub against each other, causing friction. This can make it difficult for the engine to run smoothly.

Also, a low oil level can cause an engine to overheat, damaging the parts and leading to a breakdown. The oil level needs to be checked regularly and topped up as necessary for these reasons.

Poor Quality Fuel

When your mower bog down, it’s usually the result of poor-quality fuel. Fuel in your tank may have been sitting there for months, separating and going bad due to ethanol. That can cause all sorts of problems, including clogging up your carburetor and preventing your engine from starting.

Even if your mower starts, it will probably run rough and eventually stall. To avoid these problems, always use fresh, high-quality fuel. And if you’re going to be storing your mower for more than a few weeks, be sure to add a fuel stabilizer to the fuel tank. This will help keep the gas fresh and prevent any ethanol separation.

These are some of the most typical causes why your lawn mower might bog down. By troubleshooting and addressing the problem, you can run your mower smoothly again in no time.

Solutions for Bogging Lawn Mower

Solutions for Bogging Lawn Mower

A bogging lawn mower is a common problem that several factors can cause. Here are some solutions to help you get to the bottom of the problem so you can get back to mowing your lawn:

Keep the Grass Short

Bogging lawn mowers are a common problem that is a nuisance for homeowners. The reason for this is simple: when the grass is too long, the mower struggles to cut through it. This can cause the blades to stall and the engine to overheat.

In extreme cases, the mower may even catch fire. The solution to this problem is simple: mow more often. By keeping the grass short, you will make it easier for your mower to cut through it.

Also, you will prevent thatch build-up and pest infestations. So, if you want to keep your lawn looking its best, be sure to mow it regularly.

Sharpen the Blades Regularly

Bogs occur when your lawn mower’s engine doesn’t have enough power to turn the blades. This usually happens because the mower blade is either damaged or dull. A damaged blade will cause your lawn mower to bog down because it can’t cut through the grass properly.

Your lawn mower will also bog down if the blade is dull because it cannot cut the grass as fast. The solution is to ensure that the blades are sharpened regularly. Sharp blades will be able to cut through the grass more easily, preventing it from bogging down the mower.

Using a sharpening kit for blades, you can do this yourself, or you can have them professionally sharpened. Maintaining sharp blades will prevent bogs and keep your lawn mower running smoothly.

Check the Bearings or Bushings

Check the Bearings or Bushings

If your lawn mower starts bogging down when you try to cut grass, the problem may be with the bearings or bushings. The bearings allow the blades to rotate freely, while the bushings help to keep the blades in place.

Over time, these parts can become worn out, making it difficult for the blades to turn. As a result, your lawn mower may start slowing down. The best way to fix this problem is to take your lawn mower to a qualified technician who can replace the bearings or bushings.

Check the Airflow and the Fuel Flow

You must check your lawn mower’s airflow and fuel flow systems if it’s bogging down. If the airflow is restricted, the engine will run hot and could seize up. A restricted fuel flow will deprive the engine of enough fuel and cause it to bog down.

  • You can check the airflow by removing and cleaning the air filter. Let the engine run for a few minutes after starting it. If the engine is still bogging down, you need to check the carburetor.
  • Clean the carburetor bowl when you are checking the carburetor. After starting the engine, let it run for a while. It may be necessary to replace the carburetor if the engine still bogs down.
  • To check the fuel flow, remove the fuel line from the tank and blow through it. If there is any restriction in the fuel flow, you will need to replace the fuel filter.

Adjust or Replace the Damage Deck Belt

The drive belt is located under the lawn mower’s deck and is responsible for driving the blades. If the belt is impaired, the blades stop spinning, making it difficult to cut grass. The belt should be removed and inspected for deterioration if you suspect it is a problem.

A sabotaged drive belt must be replaced. If the deck belt is not damaged, you can try adjusting it. Tighten the tensioner and move the belt to a different position on the pulley. Check whether it persists by tightening the strap.

Check the Engine Oil Level

Keeping the engine of your mower well-oiled will help to ensure that it runs smoothly and efficiently, with minimal bogging. The first step is to check the oil level. Most mowers have an oil dipstick near the engine, which checks the current status. In case of a low oil level, add more oil until it reaches the “full” line on the dipstick.

It’s also important to regularly change your mower’s oil, as old oil can become gunky and cause problems. Consult your mower’s manual to find out how often you should change the oil. By taking these simple steps, you can keep your mower running like a dream and avoid any frustrating bogging issues.


Some of the most frequently asked questions about lawn mower bogging down are as follows:

Q: Why does my lawn mower chug?

Why does my lawn mower chug

Having a dirty air filter may cause your mower to chug. Air filters help keep the engine clean by trapping particles. Over time, this filth can clog the air filter, preventing it from doing its job. This can cause the engine to work harder and lead to performance problems.

Q: Why does my lawn mower pulsate?

A blockage in the fuel supply could cause your mower to pulsate. When fuel can’t flow properly to the engine, it is likely to misfire and produce a pulsating sound. Inspect your pump line and make sure there are no clogs or restrictions. If you need to clean or replace your fuel filter, do so according to your mower’s instructions.

Q: Can spark plugs cause surging in the bogging mower?

Yes, the spark plugs may be causing the surging in the mower. When the plugs become fouled, they can cause a misfire that will create a jerking motion in the engine. You can test this by cleaning or replacing the spark plugs and see if the problem goes away.

Q: What are the signs of a bad spark plug in a bogging lawn mower?

A few signs may indicate you have a faulty spark plug in your bogging-down mower. These include engine misfiring, high fuel consumption, engine surging, and lack of acceleration. Any of these issues need to be diagnosed and repaired by a qualified technician. As soon as possible, nip these signs in the bud to avoid more severe problems.


It’s always a good idea to be proactive about maintenance and repairs, especially if you’re noticing any signs of trouble with your mower. Maintaining your lawn mower with simple tasks, such as checking the oil level and changing the air filter, can help to prevent it from bogging down.

We hope this article helped you troubleshoot the potential causes of your mower bogging down. By following the simple solutions in this article, you can troubleshoot and hopefully fix the problem of your bogging-down lawn mower.

If you still experience problems after trying these steps, be sure to consult a professional technician for assistance.

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