Why won't my mower start without starting fluid? - HowTL (2023)

Published inLast update:

Owning a lawnmower can be an investment, especially in warmer climates when grass grows faster than normal. It can also be stressful when you need to mow the lawn and the mower won't start.

He knew that he had to mow the lawn before the guests arrived; In a panic I tried my best to find out why the mower won't start without starting fluid.

There are many reasons why a lawn mower won't start without starting fluid. Perhaps it is because your mower has not been used for a long time. You could also be dealing with a bad spark plug, a dirty carburetor, or bad fluid. The worst case scenario is that the lawn mower needs to be replaced.

Curious about why a mower won't start without starting fluid? Travel with me as we explore why and find the best possible solutions.

To checkHow much oil does a lawn mower use?!

Reasons Why a Lawn Mower Won't Start Without Starting Fluid

If you need to use starting fluid to start your mower, there must be a reason for it. The first step would be to try to diagnose the problem with your mower.

If you have a toro mower, see our postToro Lawn Mower Won't Start - How To Fix It In Seconds.

Explore the reasons below by reviewing each part so you can find a possible solution.

broken or leaky carburetor

The carburetor is an essential part of the mower engine. Ensures that the correct combination of fuel and air enters the engine's cylinder. It is attached to the top or side of the engine, connected to the gas tank, and located behind the air cleaner.

Often carburettors go bad and need to be replaced and in some cases they need to be cleaned. Over time, debris and dust particles can become trapped in the carburetor, preventing it from working effectively.

Spark plug needs cleaning or replacement

Spark plugs ignite the fuel-air mixture inside the cylinder of the lawn mower. The spark plug is located in the cylinder head.

Due to carbon buildup, the spark plug will change color when the mower has not been used for a while. The dark color is an indication that the spark plug needs to be cleaned or replaced.

When spark plugs become fouled, spark quality decreases, leading to incomplete fuel combustion and reduced engine performance and efficiency.

Clogged or dirty air filter

The air filter acts as the mower's first line of defense to protect the engine from dirt getting into the carburetor.

When the grass is mowed, dirt and debris accumulate during the mowing process; If the air filter is clogged or dirty it will provide no protection and dirt and debris will eventually enter the engine and cause it to stop running.

Cracked or broken steering wheel

The flywheel is responsible for storing and applying energy for the proper functioning of the mower. The flywheel also acts as a fan that helps cool the mower's engine.

Stones can often fly under the mower and damage the flywheel.

Blockage in the Fuel Line

Blockages in the fuel line can also be one of the reasons why your mower won't start without starting fluid. Old fuel left inthe lawn mower can often dry out and clog upthe fuel line.

Bent or loose mower blade

The mower blade is designed to cut grass. There are two types of blades, the standard 2-in-1 blade designed for cutting grass and discharging or bagging clippings.

The shredder blades are 3-in-1, providing a sharper cutting edge. This mower blade not only cuts the grass, but also brings it to the surface so that the grass clippings do not fall into the mower.

Both types of blades can often bend if they get caught on a rough surface, like rocks, or get stuck if the grass is too long. They can also become loose and need to be reattached.

How much does a lawn mower weigh?

How can I get my mower to start without starting fluid?

Once you've identified the problem, you can take steps to fix it and ensure your mower starts without using starting fluid.


  • Look for a lime deposit that indicates corrosion; if the corrosion is extreme, it means the carb is broken and needs to be replaced.
  • Disassemble the carburetor and soak the parts in carburetor cleaner for one hour.
  • Reassemble the carburetor and try to rev the mower engine.
  • If there is no corrosion, the carburetor jet may be dirty; clean with carburetor cleaner.


  • After locating the spark plug, check that it is wet and gritty.
  • Using carburetor cleaner and a clean, soft cloth, wipe any debris from the spark plug.
  • If there is no spark and the spark plug appears to be dry, recover the coil control wire by rechecking for spark.
  • Also, check if the plug is loose and tighten and reconnect if necessary.

Air filter

  • Remove the air filter and examine it by holding it up to the light, and if the filter paper blocks the light, it's time to change it. A paper air filter can be cleaned by removing the dirt.
  • If your mower has a foam air filter, the telltale sign that it needs to be replaced is when the foam turns yellow. The filter is cleaned by immersing it in detergent and water to remove grease or dirt.
  • Rinse the foam filter and squeeze out excess water with paper towels. Lay out in the sun to dry for an hour; once completely dry, lubricate the filter. Before replacing the air filter, clean the filter housing with a cloth.
  • Make sure the air filter fits snugly into the accessory with no gaps.

steering wheel

  • To remove the flywheel, refer to the mower manufacturer's manual.
  • Once removed, check for cracks or broken fins; If so, you will need to replace the flywheel.
  • If there is no visible damage, the flywheel will need to be cleaned with a small bristle brush. If there is stubborn sand, use a solvent to remove it.

fuel line

  • Check for debris inside the fuel tank.
  • Remove the gas line and make sure it is clear so fuel can flow freely.
  • If the fuel lines are dry and cracked, they will need to be replaced.
  • Also, check the gas line leading to the fuel filter; the fuel filter needs to be replaced if there are fuel leaks.
  • Also, try tapping on the side of the carb to improve gas flow; if gas does not flow, it may be necessary to replace the gas line.

cutter blade

  • Remove one sheet at a time, making suresharpen and replace before removing the next blade.
  • Follow the screw marks on the blade to help determine which blade goes into the center hole and secure it. (Read here forremove stuck blade bolt from a lawn mower)
  • Place the side that says bottom or grass side facing the ground.
  • Always make sure the upper curved side of the mower blade is facing up.


Often the mower is left in storage for a while or is poorly maintained; the engine slows down; The starting fluid works as a first aid treatment. This will help the engine run, but it is not permanent.

That is why it is recommendedmake sure the lawn mower is always well maintainedTimely checking that the mower parts mentioned above are always kept in good condition.

Lawn mower maintenance will help the longevity of the mower and ensure that you are not in a situation where you need to mow, only to find that the mower will not start without starting fluid. Happy cutting!

  • Why won't my mower start without starting fluid? - HowTL (1)

    they are already

    Jason is a skilled writer and is passionate about writing about smart homes and home improvement, as well as lifestyle and lawn care. He has spent the past twelve years living in Hawaii, where he has worked closely with event planners and resort owners to hone his knowledge of luxury aesthetics and products. There he discovered his passion for DIY projects and home renovations. He currently lives in Washington DC with his family and 2 pets.

    see all posts

Top Articles
Latest Posts
Article information

Author: Francesca Jacobs Ret

Last Updated: 03/26/2023

Views: 5931

Rating: 4.8 / 5 (48 voted)

Reviews: 95% of readers found this page helpful

Author information

Name: Francesca Jacobs Ret

Birthday: 1996-12-09

Address: Apt. 141 1406 Mitch Summit, New Teganshire, UT 82655-0699

Phone: +2296092334654

Job: Technology Architect

Hobby: Snowboarding, Scouting, Foreign language learning, Dowsing, Baton twirling, Sculpting, Cabaret

Introduction: My name is Francesca Jacobs Ret, I am a innocent, super, beautiful, charming, lucky, gentle, clever person who loves writing and wants to share my knowledge and understanding with you.