7 Reasons Your Lawn Mower Won't Start - Backyard Boss
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7 Reasons Your Lawn Mower Won’t Start

Keeping your lawn healthy is crucial for maintaining your home’s curb appeal. However, when your lawn mower doesn’t want to start, it can quickly become frustrating and time-consuming. Fortunately, you can easily fix many of these issues.

Explore the common problems that can cause a lawn mower to fail to start and find solutions to keep it running. Whether you’re a seasoned lawn care professional or a first-time homeowner, it’s best not to leave the problem unresolved. Diagnose and fix the issues so your lawn can be beautiful once more!

Empty Gas Tank

An empty gas tank is one of the most common reasons a lawn mower won’t start. Before you try other troubleshooting steps, check the fuel level in your machine. If the tank is empty, add more gas and try starting the engine again. It’s also worth noting that using old or stale fuel can cause problems with your lawn mower’s engine, so be sure to use fresh gas whenever possible.

Dirty Air Filter

Another common reason is a dirty air filter. If it is clogged with dirt and debris, it can prevent air from reaching the engine and cause starting problems.

To clean the filter, remove it from the lawn mower, tap it gently to dislodge any loose dirt, and wash it with soap and water. Be sure you allow the filter to dry completely before reinstalling. A clean air filter not only helps the engine start more easily, but it can also improve the overall performance and lifespan of your lawn mower.

If you see your filter is damaged or still appears to be very dirty after cleaning, it might be time to change the filter altogether.

Defective Spark Plug

The spark plug is responsible for creating a spark that ignites the fuel in the engine — If it’s not working, the engine won’t start. To fix this issue, remove the spark plug and check for any signs of damage or wear. If the spark plug is dirty or worn, replace it with a new one. Use the correct type of spark plug for your lawn mower, as using the wrong one can cause starting problems and damage the engine. Installing a new one is a quick and easy fix that can help your lawn mower start and run more smoothly.

Loose or Damaged Wiring

The wiring is responsible for transmitting power from the battery to the engine. If there are any loose or damaged connections, the engine won’t receive the power it needs to start. To fix this, inspect the wiring and look for any loose connections, frayed wires, or other signs of damage. If you find any problems, repair or replace the wiring as necessary. Be sure to disconnect the battery before working on the wiring to avoid the risk of electric shock.

Faulty Carburetor

The carburetor mixes air and fuel in the engine. If it’s not functioning well, the engine won’t start. Cleaning the carburetor with the proper cleaner should fix this problem. However, if that solution doesn’t work, you may need to replace the carburetor. It is a more advanced repair that may require some mechanical expertise. Therefore, if you’re not comfortable doing it yourself, it’s best to take your lawn mower to a professional.

Incorrect Oil Level

If the oil level is too low or too high, it can cause starting problems and damage the engine. To check it, locate the oil dipstick on your lawn mower and remove it. Wipe the dipstick clean with a rag, then reinsert it into the oil fills tube without screwing it in. Remove the dipstick again and check the oil level. If it is too low, add more oil to the lawn mower until it reaches the appropriate level. If it is too high, drain some of it. Once you’ve adjusted the oil level, try starting the lawn mower again.

Clogged Underside of Your Mower

Over time, grass clippings, dirt, and debris can accumulate on the underside of your lawn mower, which can clog the cutting blades and prevent the engine from starting. To fix this, turn off the lawn mower and disconnect the spark plug wire to prevent accidental starting.

Next, carefully tilt the lawn mower and use a scraper or brush to remove debris from the underside. Be sure to wear gloves and eye protection to avoid injury. Once you’ve removed the debris, reattach the spark plug wire and try starting the lawn mower again.

Rev Your Engines!

There are several reasons why your lawn mower may not start. By understanding these issues and their solutions, you can troubleshoot and repair, saving time and money. However, if you’re not comfortable making the repairs yourself or unable to identify the problem, it’s best to take your lawn mower to a professional for assistance. With proper maintenance and care, it should start easily and run smoothly for years.

Did you face any other issues why your lawn mower didn’t start? Share your experience below!

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