Starting an old small engine that won’t start can be a frustrating experience. Whether it's a lawn mower, snowblower, or generator, small engines can be prone to issues over time. Understanding the common causes of these starting problems and how to troubleshoot them can save you time and money on repairs. In this guide, we’ll walk you through the steps to get your old small engine running again, focusing on the role of the engine starter and tips for overcoming common issues.
1. Common Reasons Why an Old Small Engine Won’t Start
Before diving into troubleshooting, it’s important to understand some of the typical reasons why small engines fail to start. These reasons include:
Fuel Problems: Stale fuel, clogged fuel lines, or a dirty carburetor are some of the most common fuel-related issues.
Spark Plug Issues: A dirty or faulty spark plug can prevent the engine from firing.
Air Filter Blockage: A clogged air filter can restrict airflow and prevent the engine from starting.
Engine Starter Problems: The engine starter itself might be malfunctioning, causing the engine to fail to turn over.
Once you have a basic understanding of potential issues, you can begin the troubleshooting process.
2. Step-by-Step Guide to Starting an Old Small Engine
Follow these steps to diagnose and fix common problems that may prevent your small engine from starting.
2.1. Check the Fuel
Old fuel is one of the top causes of small engine starting issues. Gasoline degrades over time, leading to gumming and varnishing inside the carburetor and fuel system. Here’s how to deal with it:
Drain the old fuel: If the fuel in the tank is more than 30 days old, it’s best to drain it out. Use fresh gasoline mixed with the proper fuel-to-oil ratio for two-stroke engines, or pure gasoline for four-stroke engines.
Clean the fuel lines: Use a fuel line cleaner to ensure no old fuel or debris is blocking the lines.
Check the fuel filter: If your engine has a fuel filter, inspect it for any signs of clogging or damage.
2.2. Inspect the Spark Plug
A dirty or worn-out spark plug can make it difficult for your engine to start. Here’s how to check and clean the spark plug:
Remove the spark plug: Use a spark plug wrench to unscrew the plug from the engine.
Inspect the spark plug: Look for signs of wear, corrosion, or carbon buildup. If the plug is damaged or heavily worn, replace it with a new one.
Clean the spark plug: If the spark plug looks dirty, clean it with a wire brush or use a spark plug cleaner tool. Make sure the spark plug gap is set to the manufacturer’s specifications.
Reinstall the spark plug: Once cleaned or replaced, reinstall the spark plug and ensure it is securely tightened.
2.3. Examine the Air Filter
A clogged air filter can restrict the flow of air to the engine, preventing it from starting. Here’s how to check and clean the air filter:
Remove the air filter: Open the air filter housing and remove the filter. Inspect it for dirt, debris, or signs of damage.
Clean the air filter: If the filter is dirty, clean it with warm water and mild soap, or tap it out gently to remove dust. Let it dry completely before reinstalling.
Replace if necessary: If the air filter is too damaged or clogged, replace it with a new one.
2.4. Check the Engine Starter
If your engine isn’t turning over, the engine starter might be the culprit. Here's how to diagnose and troubleshoot starter issues:
Listen for the starter sound: When you turn the key or pull the cord, listen carefully. If you hear a clicking sound or no noise at all, the starter may be malfunctioning.
Inspect the starter motor: If there’s no sound or a weak clicking noise, the starter motor could be faulty. In this case, you may need to replace the motor.
Check the battery: If your engine starter is battery-powered, a low or dead battery might be the cause. Charge the battery fully or replace it if necessary.
Check the starter solenoid: If the starter motor is receiving power but isn’t turning the engine over, the starter solenoid may need to be replaced.
2.5. Pull the Starter Cord Properly
If the engine starter mechanism seems fine, but the engine still won’t start, make sure you’re pulling the starter cord properly:
Firmly grip the cord: Ensure that the starter cord is fully pulled out and not jammed or stuck.
Pull with steady force: Pull the cord with steady, strong force rather than quick jerks, as this can help engage the engine starter more effectively.
3. Additional Troubleshooting Tips
If the engine still won’t start after checking the fuel, spark plug, air filter, and starter, there are a few other things to check:
3.1. Carburetor Issues
If your engine has a carburetor, it may be dirty or clogged with old fuel. Carburetor cleaning kits are available to help you clean the jets and internal passages.
3.2. Check the Kill Switch and Safety Features
Make sure the engine kill switch is in the "on" position and that any safety features, such as the blade brake on a lawn mower, are disengaged.
3.3. Inspect the Engine Oil Level
If the oil is low, it can cause the engine to seize. Always check the oil level and top it up if necessary.
4. Preventative Maintenance to Avoid Future Starting Issues
Preventing starting problems in the future is all about maintaining your small engine properly. Here are some tips to keep your engine in good working order:
Use fresh fuel: Always use fresh gasoline and avoid storing fuel for extended periods.
Store your engine properly: If you plan to store your small engine for the offseason, drain the fuel or add a fuel stabilizer to prevent gumming.
Regularly clean and replace parts: Periodically inspect and clean the air filter, spark plug, and carburetor. Replace worn-out parts as needed.
Check the oil: Always maintain the proper oil levels and change the oil according to the manufacturer’s schedule.
5. Conclusion
Getting an old small engine to start can be a bit of a challenge, but with the right approach, most issues can be resolved. By checking the fuel, spark plug, air filter, engine starter, and performing basic maintenance, you can often get your small engine running again. Regular maintenance is key to preventing future problems, so keep your engine well-tuned, and it will serve you for many more seasons to come.
