Possible Causes:
* Faulty Fuel Injectors: A leaking injector can spray fuel directly into the engine's cylinders, past the piston rings, and into the crankcase. This is a common cause.
* Carburetor Issues (if applicable): If your 84 Ford 351 still has a carburetor, a faulty float or needle valve could allow excessive fuel to flow into the engine. A stuck float is a classic symptom of this.
* Cracked or Damaged Fuel Lines: A leak in a fuel line near the engine could allow fuel to seep into the engine compartment and potentially into the crankcase.
* Pressure Regulator Problems: A malfunctioning fuel pressure regulator can cause excessive fuel pressure, potentially leading to leaks and fuel entering the engine oil.
* Clogged PCV Valve or System: While less likely to be the *primary* cause of fuel in the oil, a blocked PCV (Positive Crankcase Ventilation) system can create excessive crankcase pressure, potentially forcing fuel past seals. It's more likely to worsen the problem if another issue is already present.
* Damaged/Worn Piston Rings/Cylinder Walls: Severe wear on these components can allow fuel to bypass the piston rings and enter the crankcase. This is usually accompanied by other symptoms like excessive blue smoke from the exhaust.
What to Do:
1. STOP DRIVING IMMEDIATELY: Continuing to run the engine with fuel in the oil will cause significant damage. The fuel will dilute the oil, reducing its lubricating properties, potentially leading to catastrophic engine failure.
2. Check the Oil: Check the oil level. If it's significantly higher than normal and smells strongly of gasoline, you've confirmed the problem. The oil may also look thinner or have a different color than usual.
3. Drain the Oil: Drain the oil and replace it with fresh oil and a new filter. Do not drive the vehicle again until the underlying cause has been determined and addressed.
4. Inspect: Carefully examine the engine compartment for any visible fuel leaks. Look closely at the fuel injectors, lines, carburetor (if applicable), and fuel pressure regulator.
5. Professional Diagnosis: Finding the exact source of the fuel leak is crucial and often requires a mechanic's expertise. They have the tools and experience to diagnose the problem effectively and safely. Avoid trying major repairs yourself if you lack experience.
Important Considerations:
* Fuel-contaminated oil is extremely flammable. Take precautions when handling it.
* Do not attempt to start the engine again until the problem is solved.
Getting this problem addressed promptly is vital to preventing expensive engine repairs or even a complete engine failure. A mechanic will be able to properly diagnose and fix the root cause of the fuel leak.
