1. Fuel System Issues
* Fuel Freshness: Old gasoline can gum up the carburetor and prevent proper fuel flow.
* Solution: Drain the old gas and replace it with fresh, high-quality fuel.
* Fuel Line Blockage: The fuel line might be clogged, preventing fuel from reaching the carburetor.
* Solution: Check for kinks or blockages in the fuel line. Replace it if necessary.
* Carburetor Issues (Despite Cleaning):
* Float Level: The float inside the carburetor controls fuel level. If it's out of adjustment, the engine may not receive enough fuel.
* Fuel Filter: A clogged fuel filter will restrict fuel flow.
* Jet Blockage: Tiny passages within the carburetor can get clogged even after cleaning.
* Solution: Consider a more thorough carburetor cleaning by a professional, or replacement if it's very old.
2. Ignition System Issues
* Spark Plug Connection: Ensure the spark plug is securely connected to the spark plug wire.
* Solution: Tighten the spark plug wire connection.
* Spark Plug Wire: A broken or damaged spark plug wire will interrupt the spark.
* Solution: Inspect the wire for cracks or damage. Replace if necessary.
* Ignition Coil: The ignition coil generates the spark. A faulty coil won't produce a strong enough spark.
* Solution: Test the coil with a spark tester. Replace it if it's faulty.
3. Engine Compression
* Low Compression: Worn engine components, such as rings or valves, can lead to low compression, making it hard to start.
* Solution: A compression test can reveal low compression issues. In many cases, this requires professional repair.
4. Starter/Battery Issues (If Applicable)
* Starter Problems: A faulty starter won't crank the engine.
* Solution: Check the starter for signs of damage or wear. Replacement may be necessary.
* Battery Issues: A weak or dead battery won't provide enough power to crank the engine.
* Solution: Charge or replace the battery.
5. Air Intake Issues
* Air Filter Blockage: A clogged air filter can restrict airflow and prevent the engine from running properly.
* Solution: Clean or replace the air filter.
6. Other Factors
* Oil Level: Low oil can damage the engine. Ensure the oil level is correct.
* Choke: On engines with a choke, ensure the choke is in the correct position.
* Flooding: If the engine has been flooded with fuel, you need to let it dry out before trying to start it again.
Troubleshooting Tips:
* Listen Carefully: Pay attention to any unusual sounds the engine makes.
* Check for Spark: Remove the spark plug and ground it to a metal part of the engine. Look for a strong, blue spark when you crank the engine.
* Check for Fuel Delivery: Temporarily disconnect the fuel line at the carburetor and try to crank the engine. Fuel should flow out of the line if there's no blockage.
* Consult the Manual: Your engine's manual will have specific troubleshooting steps and diagrams.
If you're not comfortable tackling these repairs yourself, it's best to take your engine to a qualified small engine repair shop. They have the tools and expertise to diagnose and fix the problem efficiently.
