oil on spark plug

Causes of Oil on Spark Plug

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Top Causes of Oil on Spark Plugs

Oil is crucial to keeping your engine lubricated and functioning properly, however it shouldn’t end up on your spark plug of all places. If it does it can be a symptom of a more significant problem with your engine.

In this article we will go over the common causes of oil getting onto your spark plug. We’ll also take a look at some of the common indicators that it has occurred. At the end we will answer some frequently asked questions around this topic.

1. Leaky Seal Due to Failed O-ring

Leaky O-rings are a common cause of oil getting onto the spark plug. These rings can become brittle and crack over time, leading to oil making it’s way through the seal and onto the threads of the spark plug. If this occurs you should look for a replacement.

2. Piston Compression Ring issues

Piston compression rings are responsible for sealing the space between the cylinder wall and the piston. They collect oil from the cylinder walls, moving it to the pan which prevents oil leakage within the combustion chamber. Over time they can become worn leading to oil getting all around where it shouldn’t be.

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3. Blown Head Gasket

Between the engine block and the piston head sits the head gasket, it seals off the combustion chamber preventing oil from getting onto your spark plug. If it has blown then oil can easily make its way to your spark plug threads.

4. Worn out Intake Valve Seal

If the intake valve seal becomes worn then the engine oil can enter the crank case and also get onto the spark plug. If this occurs it is best to replace the intake valve seal as soon as you can.

5. Damaged Piston

As pistons are under a lot of pressure every time you use your vehicle, over time regular wear and tear can really take its toll. Damaged and faulty pistons and cracked cylinder walls are all problems that might cause oil to get onto your spark plug.

Symptoms of Oil on the Spark Plug

Here we are going to go over some of the common symptoms that there is engine oil on the spark plug.

1. Gasoline Smell coming from Exhaust

With oil the spark plug your car is going to have a strong gas smell coming from the exhaust. This is because it creates a richer fuel mixture, particularly during startup.

2. Blue Smoke

A spark plug that is dirty with oil doesn’t easily create a good spark. The engine gets around the problem by increase the air to fuel ratio, this makes the smoke from the exhaust pipe become a blue color.

3. Decreased Fuel efficiency

As mentioned previously when the spark plug is dirty or has oil on it, it’s not as efficient at creating a spark. This means that it has to increase the fuel in the cylinders to keep the pressure in the combustion chamber sufficient. The result of this is using more fuel.

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1. Is it safe to drive with oil on spark plugs?

Yes, you may drive with oil on your spark plugs, but only temporarily. If the problem persists, it is not safe to drive with oil on a spark plug as it could be a symptom of a bigger more serious problem.

Another thing to consider is the fact that having oil on your spark plug decreases fuel efficiency.

2. How to get oil out of spark plugs?

If there’s oil in the spark plug wells, you might be wondering what you need to do to get it out. The truth is that it’s more important to find the source of the problem and fix it. Getting oil out of a spark plug is not as simple as just cleaning it one time. Ideally, you should try to find the source of the problem. Because the oil is going to find its way inside the compression chamber again and again. This is why it is important to sort out the root problem. For example, if your O-rings are damaged, you need to fix them first, and then you are good to go!

But if there is excess oil, you can get a carb cleaner. You can spray this carb cleaner into the plug holes and allow the oil to go back into the combustion chamber.

3. Can we reuse spark plugs?

Yes, once your car has been repaired, there is no harm in using the same spark plugs, as long as they’re clean. Remember, this issue is not about getting oil on spark plugs. It is more about “how” the oil got there. You can use a carb cleaner to spray down all the grease and let it dry. After they dry, you can reuse them.

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If any vehicle is giving symptoms of oil on the spark plug, you should examine them right away. Therefore, if there are any oil leakages into the spark plug, it is an indicator of a serious problem. You must take it into consideration and repair it promptly

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