Westinghouse iGen4500DFcv: Gasoline Taste in Propane Mode

Understanding the Problem

The Westinghouse iGen4500DFcv is a dual-fuel inverter generator that lets you run on either gasoline or propane. This flexibility is valuable—but it introduces a complexity that single-fuel engines don’t have: two separate fuel systems that share some components. When you detect gasoline smell or taste (literally tasting it in the air or noticing it on your hands) while running in propane mode, it’s a sign that gasoline is contaminating your propane fuel path.

This isn’t just an annoyance. Gasoline in the propane circuit can affect combustion quality, reduce efficiency, and in rare cases, cause hard starting or rough running. The good news: most causes are preventable or fixable with basic tools and patience.

At-a-Glance: Most Likely Causes

Diagnostic Walkthrough

Follow these steps in order. Start with the cheapest and easiest, and work your way toward more involved repairs.

1. Verify you’re actually in propane mode. Check the fuel selector switch on your iGen4500DFcv. It should be clearly marked “LP” or “Propane.” Confirm the switch is fully seated in that position. Sometimes a partially engaged switch can allow both fuel systems to feed simultaneously. Also check that your propane tank valve is fully open and the regulator is functioning (you should hear a slight hiss when you open the tank valve).
2. Run the carburetor dry before switching fuels. This is the single most common cause. Before switching from gasoline to propane, turn off the fuel valve on the gasoline tank and let the engine run until it stalls (usually 2–5 minutes). This purges residual gasoline from the carburetor bowl and intake. Restart on propane and run for 30 seconds. If the smell is gone or greatly reduced, you’ve found your answer. Make this a standard procedure every time you switch fuels.
3. Inspect fuel lines for cracks or loose connections. Visually examine the rubber fuel line running from the fuel selector valve to the carburetor. Look for cracks, splits, or whitish deposits (fuel residue). Check that both ends are clamped securely with fuel-line clamps. A loose or cracked line can allow gasoline vapor to seep into the propane path. If you find damage, replace the fuel line with a new one rated for dual-fuel use.
4. Check the fuel selector valve for leaks. With the engine off and cool, look at the fuel selector valve (usually a three-way valve mounted on or near the carburetor). Wipe it dry with a clean rag. Now switch it to propane mode and wait 30 seconds. Look for any wet spots or drips on the valve body or its connections. Gasoline seeping from the valve indicates worn O-rings inside. If you see leaks, the valve needs to be replaced or rebuilt.
5. Smell the exhaust directly. Start the engine in propane mode and let it warm up for 2 minutes. Carefully (and briefly) smell the exhaust outlet. A strong gasoline odor in the exhaust—rather than just the air around the engine—suggests gasoline is being burned in the combustion chamber, meaning it’s definitely in the propane fuel circuit. This confirms a fuel-system issue rather than just residual smell from previous operation.
6. Inspect the carburetor bowl for gasoline residue. If you’re comfortable working with small engines, locate the carburetor bowl (the reservoir at the bottom of the carburetor). With the engine off and cool, place a rag underneath and carefully loosen the bowl drain screw (usually a small bolt at the lowest point). Let any fuel drain into the rag. Smell it: if it’s pure gasoline or a strong gasoline smell, the carburetor bowl wasn’t fully drained before the last propane switch. Tighten the drain screw and repeat the fuel-purge procedure (step 2).
7. Check propane regulator function. A faulty propane regulator can create a vacuum that draws gasoline vapor backward through the fuel selector valve. Ensure the regulator is securely attached to the propane tank and that the outlet connection to the fuel selector is tight. If you suspect regulator failure, consult the Westinghouse manual for your model’s regulator specifications and consider having a propane technician test it.
8. Run a controlled fuel-mode switch test. Fill the gasoline tank with a small amount of fresh fuel (just enough to test). Start the engine on gasoline and let it run for 30 seconds at idle. Then switch to propane mode and run for 2 minutes. If the gasoline smell is present immediately after switching, the issue is likely incomplete gasoline purge or a leaking fuel selector valve. If the smell appears after several minutes of propane operation, the carburetor bowl may not be fully isolated.

Parts You May Need

• Fuel selector valve (dual-fuel type, specific to iGen4500DFcv)
• Fuel line (rubber, dual-fuel rated, appropriate diameter)
• Fuel-line clamps (stainless steel, correct size)
• Carburetor rebuild kit (with O-rings and gaskets)
• O-ring assortment (for fuel selector valve)
• Carburetor cleaner (non-flammable, safe for small engines)
• Fresh gasoline (for purging)

When to Call a Pro

Contact a certified small-engine technician or Westinghouse service center if:

• You’ve run the fuel-purge procedure multiple times and the gasoline smell persists in propane mode.
• You find gasoline actively dripping from the fuel selector valve or carburetor.
• The fuel smell is accompanied by hard starting, stalling, or rough running in propane mode.
• You’re uncomfortable removing or inspecting the fuel selector valve or carburetor.
• The generator is still under warranty; opening the fuel system yourself may void coverage.
• You suspect the propane regulator is faulty (this requires specialized testing equipment).

Frequently Asked Questions

Is it safe to run the generator with gasoline in the propane circuit?

Short-term, yes—the engine will still combust the fuel. However, it’s not ideal. Gasoline and propane have different combustion characteristics, and mixing them can reduce efficiency, increase emissions, and potentially cause uneven running. More importantly, it’s a sign of a leak or improper fuel isolation, which should be corrected to prevent larger problems.

Why does my generator smell like gasoline even after I switch to propane?

The most common reason is that you haven’t fully purged the carburetor of gasoline before switching. Gasoline can linger in the carburetor bowl and intake for several minutes. Always run the engine on gasoline with the fuel valve off until it stalls before switching to propane. The smell should disappear within 30–60 seconds of running on propane after a proper purge.

Can I use old gasoline in my iGen4500DFcv?

No. Old or stale gasoline (more than 30 days old without fuel stabilizer) can gum up the carburetor and leave sticky residue that contaminates the fuel selector valve. Always use fresh, clean gasoline, and add a fuel stabilizer if you plan to store the generator for more than a month. When switching to propane, use the fuel-purge procedure to clear out any old fuel.

How often should I switch between gasoline and propane?

There’s no set schedule, but if you alternate fuels regularly (weekly or more), make sure you’re following the proper purge procedure every time. If you use one fuel for extended periods (weeks or months), purge the carburetor thoroughly before switching to the other fuel. Infrequent switching is actually easier on the fuel system because the carburetor has time to fully dry out.

Disclaimer

This article provides general troubleshooting guidance for the Westinghouse iGen4500DFcv Dual-Fuel Inverter. It is not a substitute for your model’s owner’s manual or service manual. Always consult the manufacturer’s documentation for your specific unit before performing any maintenance or repairs. Fuel systems can be dangerous if mishandled. If you are unsure about any step, stop and contact a qualified technician. Westinghouse and the manufacturer are not responsible for damage or injury resulting from improper diagnosis or repair.

For official support, visit https://www.westinghouse.com/support/

Source: Information adapted from official manufacturer documentation (reference). Always consult your generator owner’s manual for model-specific procedures.