Fuel Delivery Problems:
* Empty or Low Fuel Tank: The most obvious! Check the fuel gauge and fill the tank if needed.
* Fuel Filter Clogged: A dirty fuel filter restricts fuel flow. This is a relatively easy and inexpensive part to replace.
* Fuel Pump Failure: A weak or failing fuel pump can't deliver enough pressure to the carburetor. You might hear a humming sound from the fuel pump when the key is turned on (if it's still working, but weakly). A pressure gauge is needed to accurately test fuel pump pressure.
* Clogged Fuel Lines: Rust, debris, or other obstructions in the fuel lines can impede fuel flow. Inspect the lines for kinks, damage, or blockages.
* Fuel Tank Vent Blocked: A blocked vent prevents air from entering the tank as fuel is drawn out, creating a vacuum and hindering fuel flow.
Carburetor Problems:
* Clogged Fuel Jets: Tiny passages within the carburetor can become blocked with debris, restricting fuel flow. A carburetor rebuild kit is often necessary to clean or replace these jets.
* Float Level Too Low: The float in the carburetor controls the fuel level. If it's set too low, the carburetor won't get enough fuel. This requires adjusting the float level or a carburetor rebuild.
* Diaphragm Leaks (if equipped with a pump): Some carburetors have a diaphragm pump assisting fuel delivery; a leak in this diaphragm can severely reduce fuel flow.
* Stuck Choke: If the choke is stuck closed, it will restrict airflow and thus fuel flow (usually more noticeable when the engine is cold).
Other Possibilities:
* Ignition System Issues: While less likely to cause a *lack* of gas to the carb, a weak spark or other ignition problems can make it seem like there's a fuel problem because the engine won't run even if there's enough fuel.
Troubleshooting Steps:
1. Check the fuel level: The simplest check.
2. Listen for the fuel pump: Turn the key to the "on" position (don't start the engine). You should hear a brief humming sound from the fuel pump. If not, it could be faulty.
3. Inspect fuel lines and filter: Look for kinks, cracks, or rust. Replace the fuel filter.
4. Check the fuel pressure (if you have a gauge): This is the most definitive way to know if the fuel pump is delivering adequate pressure.
5. Examine the carburetor: Look for visible obstructions or leaks. This may require removing the carburetor for a thorough inspection and cleaning/rebuild.
Important Note: Working with fuel systems involves flammable materials. Take appropriate safety precautions, including working in a well-ventilated area and avoiding open flames. If you're not comfortable working on fuel systems, it's best to take your vehicle to a qualified mechanic. Attempting repairs without the proper knowledge can be dangerous and potentially worsen the problem.
