Yuck! Changed oil yesterday in my 365 GTC that sits for extended periods,and found gas in the oil. Great power,no smoke,no other symptoms. What is happening, and what is the cure?
You have fuel seeping into the motor due to leaky injectors /carbs. This dilutes the oil viscosity and, in a case where a lot of fuel is in the oil, it can begin to wash oil off of bearing surfaces . You should fix the leaks and change out the oil. I had a 308 with the notorious one-bank-cutting-out problem and each time, unburnt fuel woul just run through the cylinders of the bank with the lost spark into the oil. I first noticed it by an increase in oil temperature.
Older cars are very prone to gass in the oil. My 250 will smell like gas imediately after an oil change. I think the answer, if you don't want to pour a ton of money into the car, is drive it till it is really hot. I have been told that this will burn the fuel out of the oil, as well as all the acumulated moisture.
Unless you are running SUPER rich it is likely from a leaky needle & seat. Float bowl overflows and fuel finds its way to the cylinders. You can probably spot the problem by removing the air cleaners and peering into the carb throats with the engine OFF but key ON (might need a flashlight and mirror). If one or more are flooding, it should be apparent. You are probably having a hard starting problem as well. Attempting to "cook" the fuel or moisture from the oil by intense driving could cause excessive wear. It is always a good idea to drive until fully warmed up but it is not a substitute for proper maintenance.
And driving with gassy oil is bad too. Oil is cheap compared to overhauling a Ferrari V-12. I agree, carb cars shouldnt foul up the oil any worse than fuelie cars if they are running properly.
If you own a vintage V12 without a relatively new rebuild you will learn to live with some amount of fuel in the oil. I would say that if you don't see any rise on the dipstick there isn't "too much" fuel in the oil. After thousands of dollars and two carb rebuilds I can live with it. Sure, change the oil often, but don't be afraid to "burn" some of the fuel and other bad stuff out like moisture. I guess I could also just never drive the car.
Same thing happened to me with our 250. With the electric fuel pump on, raw gas was pouring down the carb throats. I replaced the needle valves and seats, changed the oil and everything became much better instantly. Ed
On a 12 cylinder engine you might have one fouled spark plug and not notice; it will put gas in the oil. Ken
