7 Reasons Why Your Lawn Mower Turns Over but Won’t Start!

Lawn mowers are necessary for lawn maintenance and are simple to use until you meet a stressful circumstance in which your lawn mower turns over but won’t start. But what’s causing such a commotion?

Various faults can cause your lawn mower to fail, so start troubleshooting it from the ground up, checking the fuel, spark plug, battery, filters, pump, sensors/internal connections, and choke system to see what went wrong.

This article will explain why your lawn mower turns over but doesn’t start and how to fix it.

7 Reasons Why Your Lawn Mower Turns Over but Won’t Start

There could be several reasons why your lawn mower turns over but will not start.

Here are seven possible causes for your lawn mower not starting after it turns over:

• Any issue regarding the Fuel or fuel system
• Fouled or defective Spark plug & faulty plug wire
• If the Air filter is dirty or severely clogged
• Dirty or flooded Carburetor
• Faulty Battery or battery connections
• If something went wrong in the Choke system
• Ignition coil failure

How To Fix Lawn Mower Turns Over But Won’t Start

Your lawn mower may not start due to one or more defective internal parts. However, the best approach is to identify the internal component causing the problem first and then make the appropriate change.

The steps outlined below will aid you in determining that_

1. Look For Any Fuel Related Issues

The first thing you need to check is the fuel system on your lawn mower to ensure nothing is wrong in there_

• Empty Tank/Old or Contaminated Fuel:

To start or run your mower, you will need a sufficient amount of fuel in the fuel tank, but if you do not have enough fuel, the mower will likely fail to start. So, check and refill the tank if needed.

If you have old gasoline in the tank, which has been sitting for a prolonged period, or if you haven’t replaced it recently, that fuel has surely staled and is no longer usable.

In that case, you have two ways to fix the problem:

• Add a good amount of STA-BIL Starting Fluid or some other starter lube and try to start the mower.
• Carefully drain all the old fuel out and clean the gas tank before filling in fresh gasoline.

• Using the Correct Type of Fuel:

Another concerning error that many beginners make is using the wrong gasoline or fuel mixture on their mowers.

So, make sure you are using the correct gasoline recommended for your mower, and do not forget to add a Fuel stabilizer.

• Leaking Gas/Fuel Tank:

While you are still checking the fuel system, do not forget to check the tank thoroughly and if you find any sign of leaks, fix it.

• Reduced Fuel Pressure or Restricted Fuel Flow:

If your mower has poor fuel pressure due to decreased RPM speed & Inadequate fuel supply, you will also encounter similar situations.

Even if any major elements such as the fuel line, filter, or pump. Also, test the fuel solenoid and if the solenoid turns bad, replace it.

Thus, ensure that your mower has the required fuel pressure and that those potential internal elements are in a perfect working state to confirm smooth fuel flow. 

2. Make Sure the Spark Plug & Wire Are in Good Condition

If you’ve already determined that there’s nothing wrong with your mower’s fuel system, you should check the spark plug and plug wire or lead to ensure they’re in good working order_

• Inspect The Plug Wire & Boot:

Disconnect the wire and boot from the spark plug to take the plug off.

Before you move on to inspect the spark plug, check the current condition of the wire & boot.

If the plug wire looks bad or the boot does not fit into the spark plug well, replace them.

• Clean or Replace the Plug:

Now check the spark plug and if it is dirty, you can either clean it with gasoline or spray some brake cleaner on it.

If that does not work, clean the plug with a wire brush.

However, if the spark plug is severely damaged only cleaning it will not work, so you should replace it instead.

Related Post: 5 Lawn Mower Bad Spark Plug Symptoms to Look Out For!

3. Check On The Current Condition Of The Air Filter:

If the air filter is dirty, clogged, or gummed up, it will limit airflow and allow debris to enter the mower engine, causing premature wear or failure.

• Foam Air Filter:

If you have a foam filter on your lawn mower, remove it to clean the filter and foam element. Then oil the foam filter element and squeeze the extra oil out before reinstalling the filter. If the filter looks too bad, replace it.

• Paper Air Filter:

Similarly, get access and clean it. If cleaning is not enough, replace the filter.

4. Inspect Whether the Carburetor Is Clogged or Requires Adjustments: 

• Dirty or clogged Carb:

Remove the gas line to get clear access to the carb bottom and clean it. Then check and clean the gasket ring before reassembling everything.

• Flooding Carburetor:

If you have a flooding carburetor, remove the carburetor to have a better look up close.

Take the needle off to confirm whether the ring sitting inside the needle rubber tip is worn out or not. If the ring looks bad, replace the needle.

Also, check the bowl gasket and if it needs replacement, do that. Or, simply rebuild the carburetor.

Related Post: 8 Common Lawn Mower Carburetor Problems (Fixes Included)

5. Look for Any Battery Issues:

A corroded/damaged battery, loose battery links, or worn-out cable connections can also cause starting difficulties or complete failure.

So, check the battery connections to ensure that battery cables are good in shape and tighten enough.

If the cable eyelet not rotating against the battery terminals, it means the connecting bolts are tight enough. But if not, tighten the bolts.

Then, look for any sign of corrosion around the battery terminals, and if you see it, clean the surrounding areas thoroughly with a steel brush.

Test the battery, and if it does not have enough volts required, replace the battery.

6. Inspect The Choke System for Any Potential Issue in There

If anything goes wrong or fails in the choke system, your mower will start slowly or not at all. Check that your lawn mower choke system is working properly.

If you move the throttle and the choke doesn’t react or do anything, that means you need to adjust the choke system.

Use a 5/16 socket or Torx bit to adjust the choke cable to fix the choke system.

7. Check The Ignition Coil & Make Necessary Changes: 

When the ignition coil deteriorates, it will also lead the lawn mower to witness similar difficulties.

So, test the ignition coil to confirm whether it’s good or bad.

If the test result shows that the ignition has turned bad, replace it.

Frequently Asked Questions (FAQs)

Final Verdict

If your lawn mower turns over but won’t start, check these seven possible causes straight away.

If the problem persists, contact your nearest dealer or workshop as soon as possible.

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