If your lawn mower’s engine is revving up and down, it’s likely caused by a mispositioned or stretched spring. Adjusting the governor spring or cleaning the carburetor can often resolve the issue.
When operating a lawn mower, a common issue that can arise is the engine revving up and down. This can be caused by a variety of factors, such as a mispositioned or stretched spring, or issues with the carburetor. By understanding the potential causes and taking the necessary steps, you can effectively resolve this problem and ensure your lawn mower runs smoothly.
Additionally, regular maintenance and tuning can prevent such occurrences, keeping your equipment in optimal condition for efficient lawn care. Proper diagnosis and timely adjustments are crucial in addressing the revving issue for a seamlessly operating lawn mower.
Credit: www.quora.com
Common Causes Of Lawn Mower Revving Up And Down
A common cause of a lawn mower revving up and down is a mispositioned spring or a stretched out spring, which can cause the engine RPMs to surge. Another cause could be a dirty carburetor or a leak in the intake tube.
Adjusting the governor spring or cleaning the carburetor may fix the issue.
Incorrect Spring Position
If the spring is set in the wrong position the engine RPMs surge.
Stretched Spring
Over time, a stretched spring causes engine surging.
Governor Adjustment
Surging due to the governor can be fixed by adjusting the spring.
Fixing A Lawn Mower Engine Surging
Fixing a Lawn Mower Engine Surging can be a frustrating issue for many lawn mower owners. The revving up and down of the engine, also known as surging, can be caused by a variety of factors, including a dirty carburetor, leaking intake tube, or worn-out spark plug and air filter. In this article, we will explore the steps for addressing these common issues to ensure your lawn mower engine runs smoothly.
Cleaning/servicing The Carburetor
A dirty or clogged carburetor can often be the culprit behind a surging lawn mower engine. To address this issue, start by removing the carburetor from the engine and thoroughly cleaning it. Use a carburetor cleaner to remove any built-up debris and ensure that all the components are free from blockage.
Checking For Leaking Intake Tube
A leaking intake tube can also cause the engine to surge. Inspect the intake tube for any signs of wear or damage, and replace it if necessary. Ensure that the intake tube is securely connected to the carburetor and the engine to prevent any air leaks that could lead to engine surging.
Replacing Spark Plug And Air Filter
Worn-out spark plugs and air filters can contribute to engine surging. Regularly inspect these components and replace them as needed to maintain optimal engine performance. A clean air filter and a properly functioning spark plug are essential for a smooth-running lawn mower engine.
Tuning Up A Lawn Mower To Prevent Revving Issues
If your lawnmower is revving up and down, it can be frustrating and disruptive. Fortunately, many revving issues can be resolved through regular maintenance. By tuning up your lawn mower, you can prevent revving problems and ensure smooth operation. Here’s how to perform basic tune-up tasks to keep your lawn mower running smoothly.
Replacing Spark Plug
The spark plug plays a crucial role in the engine’s performance. Over time, spark plugs can become fouled or worn, leading to revving issues.
To replace the spark plug, follow these steps:
- Turn off the lawn mower and disconnect the spark plug wire.
- Remove the old spark plug using a spark plug socket and replace it with a new one of the same model.
- Securely tighten the new spark plug and reconnect the spark plug wire.
Changing Oil
Fresh, clean oil is essential for proper engine function. Changing the oil regularly can prevent revving issues and extend the life of your lawn mower.
To change the oil, follow these steps:
- Locate the oil drain plug underneath the mower and place a container to catch the old oil.
- Remove the drain plug and allow the oil to drain completely.
- Replace the drain plug and fill the engine with fresh oil according to the manufacturer’s specifications.
Replacing Air Filter
A dirty or clogged air filter can restrict airflow to the engine, leading to revving problems. Regularly replacing the air filter is essential for optimal engine performance.
To replace the air filter, follow these steps:
- Locate the air filter housing and remove the cover.
- Remove the old air filter and replace it with a new one that matches the model of your lawn mower.
- Reinstall the air filter cover and secure it in place.
Inspecting Fuel System
Issues with the fuel system, such as clogged fuel lines or a dirty carburetor, can cause revving problems. Regular inspection of the fuel system can prevent these issues from occurring.
To inspect the fuel system, follow these steps:
- Check for any clogs in the fuel lines and ensure the fuel tank is clean and free from debris.
- If necessary, clean the carburetor and replace any worn or damaged parts.
- Ensure the fuel cap is tightly sealed to prevent air from entering the fuel system.
Common Fuel System Problems Leading To Revving
When your lawn mower revs up and down, it can be an indication of underlying fuel system issues. Let’s explore some common problems in the fuel system that can lead to this revving behavior.
Contaminated Gasoline
Contaminated gasoline can wreak havoc on your lawn mower’s performance, causing it to rev inconsistently. Water or debris in the fuel can disrupt the combustion process, leading to surging RPMs.
Vacuum Leaks Through Air Intake Manifold
Leaks in the air intake manifold can introduce excess air into the engine, causing it to run lean and rev up and down. These leaks can stem from worn gaskets or loose connections, impacting the engine’s fuel-to-air ratio.
Understanding Engine Hunting And How To Resolve It
If your lawn mower is revving up and down, it could be a result of engine hunting. This issue is typically caused by a lean-running engine. To resolve it, consider cleaning or servicing the carburetor, checking for leaks in the intake tube, and replacing the spark plug and air filter for a reliable engine.
Carburetor Blockage As Main Cause
When it comes to a lawn mower revving up and down, one of the main causes is carburetor blockage. The carburetor is responsible for mixing fuel and air to create the combustion needed to power the engine. Over time, it can get clogged with dirt, debris, or varnish buildup from old fuel. This blockage restricts the flow of fuel, causing the engine to run lean and rev up and down. To resolve this issue, the carburetor needs cleaning and servicing. Here’s a step-by-step guide to help you:- Start by locating the carburetor on your lawn mower.
- Remove the air filter cover and the air filter.
- Disconnect any linkage connected to the carburetor.
- Using a carburetor cleaner, spray into all the orifices and passages of the carburetor to remove any blockage.
- Use a small brush or toothbrush to scrub away any stubborn dirt or debris.
- Reinstall the carburetor, making sure all connections and linkages are secure.
- Replace the air filter and cover.
- Start the lawn mower and observe if the revving up and down issue persists.
Throttle Compensation By Engine’s Governor
Another factor that can cause engine hunting is the engine’s governor. The governor is responsible for controlling the throttle opening to maintain a consistent engine speed. If the governor is not functioning properly, it can lead to the engine revving up and down. To compensate for this issue, adjusting the governor spring can often resolve the problem. Here’s how you can do it:- Locate the governor spring on your lawn mower’s engine.
- Use a wrench to loosen the nut securing the spring.
- Gently move the spring in small increments, either in a clockwise or counterclockwise direction, depending on the specific instructions for your lawn mower’s engine model.
- Make sure to only make small adjustments and test the engine after each adjustment to ensure the surging issue is resolved.
Credit: www.youtube.com
Credit: www.reddit.com
Frequently Asked Questions For Lawn Mower Revving Up And Down
What Causes A Lawn Mower To Surge Up And Down?
Lawn mower surging is often caused by a misaligned or stretched spring, or a lean-running engine. Cleaning the carburetor, addressing vacuum leaks, and replacing the spark plug and air filter can fix the issue. Adjusting the governor spring usually corrects surging with a small adjustment.
What Causes A Mower Engine To Rev Up And Down?
When the spring is set wrong or stretched, the engine RPMs surge up and down. The surging is caused by a lean-running engine, requiring carburetor cleaning or intake tube inspection. Additionally, it’s important to change the spark plug and air filter for reliability.
Why Does My Lawn Mower Run Erratically?
Your lawn mower may run erratically due to a lean engine causing it to surge up and down. This is typically caused by a dirty carburetor or a leaky intake tube. Ensure to clean or service the carburetor and check/replace spark plug and air filter for a reliable engine.
Conclusion
Maintaining your lawn mower’s carburetor and checking for leaks can resolve surging issues. Regular tune-ups and replacing parts like the spark plug and air filter can ensure a smooth-running engine. Keep your mower in top shape for a flawless lawn care experience.
