what is the cause of gasoline in the oil?
Asked by Jamie Dec 05, 2012 at 03:24 PM about the 1987 Volkswagen Vanagon
Question type: Maintenance & Repair
I'm thinking of buying a pretty nice 87 Vanagon for a pretty decent price. The owner said it started
smoking badly on a very cold winter day. I checked the oil for signs of a blown head gasket. Didn't find
any water but the oil smelled strongly of gas.
5 Answers
aztec626bf answered 11 years ago
Its probably running rich and loading up with gas. Or it might be getting to many short runs. The engine runs richer when cold. If the oil never gets up to operating temp it can't burn off the excessive gas or release the moisture in the oil. A good way to check for blown head/gasket is to run engine and watch the coolant overflow for bubbles. Also look for oily residues in coolant. If it is bad enough you will notice white smoke from exhaust. Any one or all of these are symptoms.
Gas smell in the oil on a old car = bad rings. It probably smokes especially when accelerating. Factor in a rebuild or engine replacement if you negotiate a price.
aztec626bf answered 11 years ago
That is one possibility and real easy to check for. Do a compression test wet and dry and you can confirm or deni that one.
This is a common problem. I have a freshly rebuilt '87 that had the same problem, the O2 sensor harness wire breaks and grounds out on the outer shielding wire and shorts to ground causing a super rich condition. Also the fuel pressure regulator diaphragms are notorious for leaking and oil gets sucked into the intake from the FPR. Bad rings generally don't cause a fuel smell from the gasoline from my experience.
