A problem all small lawn owners can identify with is that the key won’t shut off the lawn mower. This is a common issue when you have not mowed for a while.
A malfunctioning ignition switch, a damaged key, or even a problem with the engine can cause this issue.
This article will explore the reasons why lawn mower won’t shut off with key and provide helpful tips on how to deal with it.
Different Types of Lawn Mower Keys and Their Functions
Several types of lawn mower keys are used for various purposes. The standard key, the push-button start key, the smart key, and the universal key are examples of these.
The most basic type of key is the standard key. It is used to start the lawn mower by turning the key.
The push-button start key is a more recent addition to keys. This one allows the user to start the lawn mower by pressing a button.
These are typically battery-powered and frequently used along with a standard key.
A smart key is used as an addition with a keyless entry system. You can start the lawn mower without the insertion of such keys. A button can be used to simply start the engine.
Last but not least is the Universal Key. It is suitable for a range of lawnmowers.
These keys are frequently used by landscapers and other businesses that run a variety of lawnmowers.
All the above type of keys have unique benefits and functions in various lawn-mowing situations.
Common Causes of Lawn Mower Won’t Shut Off With Key
If your mower has been sitting for some time, had a mouse nest near the ignition or anything, the key not turning it off will be quite the common issue.
In this light, here are some reasons with solutions why your mower key will not shut off the lawn mower:
1. A Faulty Ignition Switch
The key switch may be worn out or damaged, preventing the engine from shutting off.
Fix: Replace Ignition Switch
If the ignition switch has visible signs of damage, such as cracks, gaps, or discoloration, change it.
2. Loose Or Damaged Wiring
Wiring can become loose over time. This leads to a loss of electrical connection to the engine. As a result the key fails to shut off the mower.
Fix: Replace Damaged Wiring
When replacing the switch, check the wiring as well. Chances are they are damaged. Replace the wiring in this case.
3. Engine Governor Issue
The governor controls the speed of the engine and can cause it to stay running even when the key is turned off. When the governor is damaged, you can bet your mower will not shut off with key.
Fix: Repair or Replace Any Old Part
If the governor is simply malfunctioning, you may be able to repair it without needing to replace any components. Firstly, clean the governor assembly. Check for any signs of dirt, debris, or wear.
If any parts are worn or damaged, replace them with new ones. Then inspect the governor linkage and adjust it as necessary to ensure proper alignment.
Finally, if the governor is completely damaged or unrepairable, you will need to replace it.
4. Clogged Air Filter
A clogged air filter can cause the engine to continue running even when the key is turned off. This is because without sufficient air the engine is unable to properly cool down. And the combustion process cannot be completed.
Fix: Clean Air Filter
A clogged air filter must be cleaned. Use a vacuum cleaner or a brush to remove dirt and debris.
In case of extreme clogging, soak the filter in soapy water for a few minutes and then rinse it with clean water.
Replace the air filter if it is too old.
5. Fuel System Issue
A faulty fuel pump, clogged fuel filter, or a faulty injector can prevent the engine from shutting off when the key is turned.
Fix: Check Injector, Spark Plug and Others
Check for faulty fuel pump or a faulty injector. These should be replaced. A clogged fuel filter should be cleaned (replace if necessary).
Air leaks can cause fuel to be drawn into the engine, reducing the efficiency of the fuel system. Check the fuel lines and connections for cracks or leaks and repair according to the manual.
Check the spark plug and replace it if necessary. Clean or replace the carburetor.
Troubleshooting Precautions and Tips
While troubleshooting the issue, it is necessary to make sure of the following things in addition:
- Wiggle the key while in the off position to see if it helps.
- Make sure the safety switch is in the correct position.
- Check the ignition switch. It may need to be replaced to fix the issue. Additionally, the wiring may need to be checked to ensure that it is not damaged or frayed and that it is securely connected to the switch.
- Clean the ignition switch contacts with a cotton swab and some contact cleaner.
- Try a different key in the ignition in case the existing one is worn or bent.
- Check the battery connections to make sure they are tight.
- Make sure the battery is properly charged and is getting enough power.
- You may need to replace the kill wire. Be sure to purchase the correct type and size of wire for your mower.
- Inspect the ground connection to ensure it is securely fastened. Clean the ground connection and ensure the connection is tight. If the ground connection is not secure, replace it with a new one.
- Check the electrical connections to the mower for any loose connections or damage. Clean the connections with a contact cleaner.
Tips for Extending the Life of Your Lawn Mower Key and Avoiding Shut-Off Problems
Ensure that the fuel you are using is fresh and clean. Old fuel can cause carburetor problems and cause the engine to stall.
Regularly check the spark plug for dirt and carbon buildup.
Check the battery connections and terminals. Poor connections can cause the engine to stall or not start.
Moreover, your mower is there for you to use, not ‘abuse’!
Frequently Asked Questions (FAQs)
How do I know if my mower has a faulty switch?
If you find that the mower will not turn off even after the key has been removed, then the switch is likely faulty.
What causes a lawn mower to keep shutting off?
Clogged components in the engine or transmission system, e.g: clogged carburetor, fuel filter, oil filter, etc.
What is a safety key mower?
A mower safety key is a device used to shut off the engine of a lawnmower in the event of an emergency. The motor and blades of the lawn mower can only be started when the safety key is inserted and rotated to the “On” position.
How does a push lawn mower safety switch work?
The switch is typically located on the handle. When the handle is held in the “on” position, it allows an electrical connection to be made which allows the engine to run. Upon release of the handle, the electrical connection is broken, stopping the engine.