Oil leaking into the spark plug wells is an indictor of a fairly serious problem that should be inspected and repaired immediately. It is almost always due to a failing gasket or O-ring but can also be the result of a failing piston or worn valve guides.
Oil making its way into the spark plug wells will drastically affect the engines performance, leading to misfires, increased oil consumption and blue exhaust. In extreme cases, it can even lead to an engine fire. If the vehicle is exhibiting any of these symptoms, the spark plugs should be inspected immediately.
How this system works:
his issue involves two systems, the spark plugs and the engine lubrication system.
The main function of a spark plug is to ignite the fuel/air mixture in the combustion chamber. Electrical energy is transmitted through the spark plug where it jumps the gap and the spark ignites the gasoline and air mixture. Spark plugs also pull heat out of the combustion chamber, working as a heat exchanger, it pulls thermal energy from the combustion chamber and transfers it to the cooling system.
Engine oil is used to lubricate the moving parts of an engine. The constant moving of the engine parts generates heat, as well as wear and tear. Engine oil helps to minimize the friction and dissipates the heat generated by the engine.
The oil pan is where engine oil is stored. A typical oil pan will hold up to 6 quarts of oil. When the engine starts, the oil pump pulls oil from the oil pan through a part called the pickup tube. The oil then moves to the oil filter, which removes dirt and debris before it is sent to the various parts of the engine via spurt holes. Eventually it heads back to the oil pan to start the process over again.
Common reasons for this to happen:
Leaking Valve Cover Gaskets: The valve cover is a metal part found on the top of the engine, which seals the engine and helps prevent oil leaks. Between the valve cover and the engine are gaskets that tend to fail over time. Due to the high temperature of the engine the gaskets can get brittle, and start to leak. It is possible for the oil to leak into the spark plug wells. Leaking valve cover gaskets need to be repaired as quickly as possible, failing to do so can lead to further damage to the engine.
Failing O-Ring Seals: There are O-Ring seals at the bottom of the spark plug wells and if a seal starts to fail, oil can leak past these seals and into the spark plug well. Again, this issue should be repaired as soon as possible and the spark plugs should be changed as well.
Failing Piston Compression Rings: The pistons in a car’s engine have compression rings at the top of the piston and the bottom. These rings are set in grooves in the piston and help scrape excess oil from the cylinder walls and prevent oil from getting into the combustion chamber. If these rings fail, oil can make its way into the spark plugs wells. Other symptoms of failing compression rings include increased exhaust that is blue and smells oily.
Failing Piston: A piston that is running too hot can develop a hole or crack. The most common symptoms of a failing piston include rattle and knocking noises while the car is running, excessive oil burning as well as a loss of power and engine misfiring. It can also lead to oil in the spark plug wells. This is an extremely serious condition that needs to be repaired as soon as possible.
Worn Valve Guides: Valve guides help to regulate air intake by keeping the valves in place while the engine is running. Over time, valve guides can become extremely worn and will require replacement. Blue smoke and oil or ash in the spark plug wells is a common symptom of failing valve guides. Worn valve guides can lead to more serious engine problems and should be repaired as soon as possible.
What to expect:
A top-rated mobile mechanic will come to your home or office to determine the source and cause of the Oil in Spark Plug Well issue, and will then provide a detailed inspection report that includes the scope and cost of the necessary repairs.
How it's done:
A mechanic will check your valve cover gaskets, O-Ring seals, pistons and other important components. The mechanic may need to crank the car and test drive it to pinpoint the cause of the leak and produce an accurate diagnosis.
How important is this service?
Oil in a spark plug well is a very serious problem that should be repaired as soon as possible. It can do extensive damage to the engine, such as broken or warped pistons and valves. Eventually, if not repaired, the head gasket can result in the fatal destruction of the engine. There is also the potential for an engine fire if the spark plugs ignite the oil.