3406e oil in fuel tank

Pull THE HEAD? Run, Don’t play around there. If your gonna pull the head, replace it. Injector cups, injectors, all that will be done with the head on the block. Unfortunately, this is most likely how it will go. Once he pulls the head, there will be other issues that require your attention, and he will be selling you a motor job. From his side of things, it’s much easier to sell a motor job to a customer when the motor is already apart. Once the head is off there isn’t much more to do, all the labor and $$ is up Top on a Cat.

 

Keep a eye on it, white smoke with that motor can be a early sign of rebuild time. Low compression in one or two of your cylinders causes white smoke, unburnt fuel, then it clears up as you throttle up and heat rises in the cylinders.

 

You need a fuel analysis, not oil. My apologies if I misspoke earlier. I also didn't mean to discount the possibility of a loose injector, or bad injector o-rings in my earlier post, cause they are definite possibilities. But if injectors were removed and o-rings inspected, you would find it if the failure was o-rings or cups. If you see no sign of issues with either of those, you would then look towards an injector not sealing.

 

It down on power any? If it's been running normal I'd tell him not to worry about it for now you'll keep an eye on it. Algea will do that to fuel I'm pretty sure, and all the biodiesel you get at the big fuel stops doesn't help any in my opinion.

 

Have you had an oil sample taken? By someone else?

I find it difficult to believe you could have oil in your fuel without also having fuel in your oil.

I cannot think of any places where oil and fuel could mix where the oil is much higher pressure than the fuel. Fuel going to the block is very high pressure, and oil doesn't get near the oil on the low pressure side of the fuel system on it's way back to the fuel tank. The contamination can be one-way only if the pressure differential is large and the leak is small, and even then there would likely be measurable traces even if they are tiny.