Why Is My Lawnmower Running Slow? How Can I Speed Up My Lawnmower?

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Regular maintenance for a lawnmower is compulsory for efficient grass cutting and smooth operation. It is common to encounter various technical issues for lawnmowers. One of them is your lawnmower running slowly during the process.

Why is my lawnmower running slow?

A lawnmower can run slow due to clog-up issues, incorrect fule injection, faulty battery, spark plug misfire, or dirty/faulty carburetor. 

A lawnmower may run slowly during the operation for several reasons, such as

  • Clog-up issue
  • Not using the correct type of fuel
  • A bad battery
  • Spark plug misfire
  • Dirty air filter, carburetor, or spark plug

Why Is My Lawnmower Running Slow?

Is your lawnmower running slowly?

If yes, which factor is mainly responsible for this issue? Are you facing the case for a long time or just a while ago?

According to experts, a lawnmower can run slowly for a wide range of causes. So, the reasons will vary from mowers to mowers. Let’s learn them!

1. Clog-up Issue

Why Is My Lawnmower Running Slow - Clog-up Issue

One of the ordinary yet concerning issues about lawnmowers is clogging up. As you know, liquid fuel is used to power a lawnmower combustion engine.

You may notice a clog-up issue in different parts of a lawnmower, such as the air filter, the carburetor, the fuel line, the fuel filler cap, the needle seat valve, etc.

Check out each component separately and try to find out the clogging-up issue. In case you are unfamiliar with them and how they function, take expert help.

2. Not Using The Right Type Of Fuel

lawnmower Using The Right Type Of Fuel

Different lawnmowers are made differently as per brand preference. Therefore, it is not possible to use the same type of fuel for all lawnmowers.

A perfect fuel blend is necessary to ensure engine efficiency. It may occur that you are using the recommended oil for a long time.

But suddenly you changed the fuel due to unavailability. This could lead to slow operation of lawnmower and also engine inefficiency

Most importantly, using the wrong type of fuel for a prolonged time will shorten the excepted lifespan of the mower. So, it is always better to use the manufacturer-recommended fuel for your lawnmower.

3. A Bad Battery

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Have you noticed if your lawnmower battery is performing similarly to the way it used to do? Check out its performance after charging the battery for the whole night.

If the battery performance is still not up to the mark, replacing the battery is a good idea. Make sure to recharge the new battery fully before installing it.

4. Spark Plug Misfire

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The spark plug is designed to fire sparks on each turn to run the machine at full throttle.

But when any misfiring occurs in the spark plug, it can’t work at full strength. Failing to work at full throttle means the lawnmower will run slowly, unlike before.

So, why the sparks plug is misfiring? When there is a lot of dirt inside the plug or too much space exists between the components, it will misfire.

Check out the spark plug condition and take appropriate action to resolve the issue. Most plugs will last 100 hours when used regularly. If the time is exceeded, it is better to replace it.

5. Dirty Spark Plug, Air Filter, Or Blade

Dirty Spark Plug, Air Filter, Or Blade

Do you clean the spark plug, air filter, or blade regularly, especially when using the mower frequently? If not, you should.

Cleaning these components of the lawnmower will prevent dirt build-up. Additionally, you should give more importance to cleaning mower blades.

When you cut tall and thick grass, some parts may remain inside the blade. That’s why it is always better to clean up the mower blade after every cutting session. It will prevent the slow-down issue when you cut the grass the next time.

So these are all the probable causes of this query: why is my lawnmower running slow?

Why Does My Lawnmower Engine Speed Up And Slow Down?

Whether you are using a brand lawnmower or an older one, you want a smooth operation. You have no reason to run it too slowly or too fast.

Why does my lawnmower engine speed up and slow down?

Your lawnmower engine speeds up and slows down because of having debris in the fuel tank, airflow issues, a faulty spark plug, or having an old carburetor.

Several causes can be the culprit of this issue, which will vary from mowers to mowers, such as

  • Dirt/debris on the fuel tank
  • Airflow issues
  • Not getting sparks at the spark plug
  • Dirt in the fuel filter
  • Fuel is not fresh
  • Too old carburetor

How Can I Speed Up My Lawnmower?

Mowing the lawn is a time-consuming chore. You don’t want to spend your whole day cutting grass in your garden.

How can I speed up my lawnmower? The following tips can help you to speed up your lawnmower.

1. Use Sharp Blades

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The prerequisite of cutting thick or long grass is sharp blades. Unless the blades are sharp enough, you can’t mow the lawn smoothly and quickly.

Sharpen your lawnmower blades regularly so that they don’t become dull. Razor-sharp blades will help you cut grass efficiently within a short time.

If the mower blades are too dull or too old, purchase a brand new set of blades.

2. Use High-Quality Gasoline

Quality matters! We often purchase low-quality gas to save few bucks. Because of this, the machine can’t operate at 100% efficiency.

Using fresh and high-octane gasoline will speed up the mower and prevent the engine from jamming up.

3. Ensure Proper Tire Inflation

Make sure your lawnmower’s tires are adequately inflated. When tires are properly inflated, they are less likely to blow out while running at high speeds.

4. Make Tires Replacement

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Tires replacement is always welcomed, especially if they are too old and do not get your desired speed from the mower.

5. Make Sure All Parts Are Okay

If there is an issue with any lawnmower part, you can’t run the machine 100% efficiently. That’s why you want to ensure all components are working properly.

You can take the mower to a shop before starting each season to ensure nothing is wrong with the machine. Well-maintenance prevents failures!

6. You can Ditch The Governor

lawn mower governor

The governor often determines your mower engine speed. Slow engine, slow mower! If the governor is not working correctly, it is better to ditch it and replace it with a newer one.

 7. Increase The Pulley Size

lawn mower Pulley

Another thing that can increase or decrease the lawnmower speed is the pulley. When it comes to your mower, larger pulleys can provide more speed.

When increasing size, make sure to do it gradually to prevent overloading your mower. To avoid mistakes, follow the directions carefully to check how far you can go in what conditions.

8. By Cutting Grass Regularly

Don’t make a mistake cutting all grasses of your lawn at once. Instead, cut them regularly — you can start cutting long and thick grass first.

Cutting all grasses at a time will make the lawnmower blades dull as they can’t take the heavy load. Regular cutting will ensure efficiency without clogging up.

9. Checks For Leaks Or Damages

Any leakage issues in the engine will prevent the machine run at full speed. It can happen for any part of the mower. You should take instant action the moment you notice it.

10. Maintain The Right Oil Level

lawn mower Oil Level

Mowers are lubricated through oil. Failing to lubricate the machine components will lead to damaging the parts gradually. The best thing you can do is keeping the mower’s oil at the correct level.

Therefore, you can follow these tips to answer this question: how can I speed up my lawnmower?

What Causes A Lawnmower To Run Sluggishly?

Lawnmowers are supposed to run smoothly as long as there is no internal issue. But, over time, you may see some cases which prevent you from running them properly.

What causes a lawnmower to run sluggishly? If your lawnmower is running sluggishly, many internal issues can be the reason for it.

Serial No. Causes Of A Lawnmower Running Sluggishly
1 Your lawnmower battery has become too old or already damaged.
2 Your lawnmower blades have a dirty or rusting issue in the edges.
3 You are not using fresh petrol, which lacks combustibility.
4 Your drive belt has become damaged or disengaged.
5 You are using less effective fuel to save some bucks.

Why Is My Mower Idling Low?

Idler speeds for lawnmowers range from 1,200 to 2,000 rpm. Ensuring the perfect amount of fuel flow into the carburetor is what the idling system does. Without it, you can’t run the combustion process smoothly.

Why is my mower idling low?

Mowers that can’t idle or idle too low will turn off automatically. This problem mainly occurs for various reasons:

  • If the air filter is full of debris and dirt
  • If you are not cleaning the fuel filter regularly
  • If you follow the wrong adjustment for the carburetor
  • If the carburetor has become excessively dirty

Wrapping Up

No one wants to use a lawnmower that runs slowly. In order to run the machine at your desired speed, first, you want to figure out this question answer: why is my lawnmower running slow?

We have outlined all the possibilities on what causes a lawnmower to run sluggishly. Thanks for reading!

Read More – Why Is My Lawnmower Battery Dying? How To Fix It?

Last update on 2021-09-30 / Affiliate links / Images from Amazon Product Advertising API