WHY IS MY CAR BURNING OIL?
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Why is my engine Burning Oil?
Several factors can contribute to a car burning oil. Worn or stuck piston rings. Worn valve seals.
Depending on where the oil leak is, your car may be burning oil inside or outside of the engine block. Most of the time, a car “burns” oil because a part that is supposed to keep oil out is no longer doing its job. Sometimes a car just uses more oil than you think it should, but if you smell something new or see smoke coming from it, it may have engine oil where it shouldn’t be and those parts are very hot.
Why do cars burn oil?
If your car is using a lot of oil, it is probably getting old. Over time, the piston rings may have worn down or gotten stuck in their grooves, making it hard for them to seal tightly against the cylinder wall.
Where do oil leaks come from?
We shouldn’t take oil leaks lightly. Not only is the oil flammable and a fire risk, but it also hurts your car and the environment when it leaks.
If your car has an oil leak, you should fix it as soon as you notice it. Most of the time, a car leaks and burns oil because of the following:
- Broken Gaskets
- Broken Seals
- Damaged Oil Filter
- Damaged Oil Pans
- Oil Plan Plug Was Improperly Installed
- Or Is Dislodged
- A Blown Head Gasket
- Bad Engine Block Seals
- Incorrect oil viscosity
Let’s take a closer look at what might be happening.
Reasons for engine oil consumption
Most stock pistons in cars have three rings.
The top and second rings seal the combustion chamber by pressing hard against the cylinder wall. This keeps the combustion gases in and the oil out.
On its way down the cylinder, the oil ring scrapes oil off the cylinder wall and puts it back into the oil sump.
Because a very thin layer of oil keeps the ring and cylinder wall from rubbing against each other, it is normal for some oil to burn during combustion. What’s “normal” in terms of oil use, though, depends on the engine.
Read this post to learn more about how piston rings work in cars.
If a car has bad valve seals, it can burn oil.
Seals on the valves also keep oil from getting into the combustion chamber.
Since oil is there to keep the seals lubricated and flexible, some of it will burn during combustion, causing the engine to use up oil.
Even so, engines that aren’t very old shouldn’t use much oil. In fact, if you use a high-quality synthetic oil, you shouldn’t need to add much, if any, top-off oil between oil changes. But just in case, make sure to check your oil often.
Blame it on friction
Even with the best care, things, like engines, wear out over time.
When rings get worn, there can be a space between the ring face and the wall of the cylinder. During operation, oil can get past the rings and burn in the combustion chamber. Worn valve seals can also cause oil to be used up.
The same thing can happen if heavy deposits cause rings to get stuck.
If you use a conventional oil that doesn’t resist chemical breakdown, ring-land deposits can form, which makes the rings stick. When this happens, the piston rings don’t float in the cylinder liner anymore, which can cause the engine to use more oil (in addition to wear).
Oil use can be caused by low-quality oil.
You might also be using an oil that doesn’t handle heat well.
Conventional motor oils are made of molecules that are light and unstable. When high heat is present, these molecules are more likely to rise out of the solution, just like water molecules rise out of a puddle when the sun is shining on it.
Because of this, the oil level in your engine drops as the oil turns into carbon deposits all over the engine.
Before I started selling AMSOIL, this is probably what happened to my Oldsmobile Intrigue. I bought cheap oil from a big-box store and scratched my head every time the dipstick showed that the oil level was low. A mechanic even checked for oil leaks (he found none).
Incorrect oil viscosity can be to blame
Another, less likely possibility is that you are not using the right viscosity of oil for your engine.
Viscosity is defined as the resistance to flow, but it’s easier to think of it as thickness. The less viscosity an oil is, the thinner it is. As you might guess, thinner oil is easier to get around worn rings or valve seals than thicker oil.
Most likely, the right viscosity of oil for your engine is written on the oil filler cap. If not, the owner’s manual or the AMSOIL Product Guide will have the information.
Some manufacturers suggest a range of viscosities, such as 5W-20 when it’s cold and 10W-30 when the temperature is above 0oF (-18°C).
Using the recommended highest viscosity can help close the gap between the rings and the cylinder wall, which reduces the amount of oil used.
Oil Burning Outside The Engine
If the oil is burning outside of the engine, it is probably leaking and landing on a hot surface. Most of the time, you can tell when oil is burning outside because you can smell it.
Broken Gasket or Seals
The engine gasket is the part that keeps oil from getting from where it should be to other parts of the engine. Over time, gaskets can break down or get holes. They are exposed to high temperatures and, as they heat and cool, their shape may change over time.
In your car, the fuel combustion that gives the engine the power to move the car forward happens at around 495 degrees Fahrenheit. This is hot enough that the metal parts of the engine and their seals do a lot of expanding.
When the car is parked, the temperature will be about the same as the air outside. So, these engine parts are sometimes exposed to temperature changes of even more than 400 degrees.
When parts grow and shrink, they leave gaps in the seals and lower the pressure in the engine, which can cause oil to leak. If your car is leaking oil, you can find out if the seals or gaskets are to blame by taking it to a mechanic and having the problem looked at.
How much will it cost to fix a broken gasket?
A broken seal or gasket will cost you about $750 on average to fix.
Damaged Oil filter or damaged oil pan
Your car can leak oil if the oil filter or the oil pan is broken. Most of the time, these problems are caused by bad maintenance or bad road conditions.
The oil pan of a car can get damaged if it drives on an uneven surface or hits something on the road. A few years ago, I hit a piece of a lawn chair, which broke mine. Most of the time, a broken oil pan will leak quickly, which will show up as a large puddle of oil. If a car’s oil pan is broken, it needs to be replaced so that the car doesn’t leak oil.
oil Pan Plug is damaged or dislodged
Sometimes, an oil pan plug can get broken or fall out. This is something you can fix yourself for less than $5.
A similar problem can happen if the oil pan plug is loose or wasn’t put in correctly. If an oil plug isn’t tightened all the way, it will cause a leak. This problem is easy to fix; the oil pan plug just needs to be put back in.
If the oil pan plug is broken, things are different. You can take the plug out and temporarily replace it with a rubber plug, but the steel thread will need to be fixed with a plug that is standard for your car’s make and model. A new drain pan can also be put in. But it won’t be free.
Check out this 5-minute video from Cars That Last if you want to learn more about your oil drain plug. When you are trying to decide how to fix your own car, it can be very helpful to see what these parts look like and how they are fixed.
Watch the video down below.
A blown Head Gasket
A blown head gasket is a big problem that will cost you more than $1000 to fix. One sign is that the car will use a lot of oil.
The car will also usually make white smoke, the radiator and coolant may be bubbling, and the oil will have a white residue. You will also notice that your car is getting too hot.
If the head gasket blows, it’s a very serious problem, and the car won’t be safe to drive. If the head gasket on your car is blown, you might not be able to drive it at all, and you certainly can’t do so without doing more damage.
Most of the time, the head gasket won’t warp unless your car gets too hot. Most of the time, a car overheats because it doesn’t have enough coolant, the water pump isn’t working right, or the radiator is broken. Coolant is an important fluid to have in your car if you want to avoid expensive repairs.
If your head gasket has blown, we hope your car is still under warranty because this will be a pricey fix. This repair is going to cost about $1500.
Engine Block Seal
Your leaking oil could also be caused by a problem with the engine block seals. This is a common problem with older cars. Over time, the oil in the car will wear down the seals.
The rubber seals on the engine block may have worn out to the point where they no longer work well. If this is the problem, then the leak will be at the top of the engine block.
Fixing the engine block seals can be very expensive. This isn’t because the part is expensive; seals aren’t that expensive. Instead, it’s because working on an engine can cost up to a thousand dollars in labor.
Camshaft Seals
Most new cars don’t have timing belts because timing belts are an old part that have been replaced by timing chains, which are stronger. Before, a vehicle’s timing belt had to be changed every 100,000 miles or so, or else a broken timing belt could ruin the engine. Many older cars, including mine, still have a timing belt.
If your car has a timing belt, the leak could be coming from the camshaft seal. The camshafts of your car are on the inside of the engine, just like the crankshaft. The seal goes on the end of each camshaft and keeps oil from leaking out and burning in the rest of the engine.
If the problem is with the camshaft, oil will be on the back of the engine just below the valve cover. The engine may also be pouring out smoke. Sometimes you can smell smoke but not see it.
Seals For The Front And Rear Crankshafts
Like the camshaft, the crankshaft is a part of the engine that sticks out of the engine. Like the camshaft, the ends of the crankshaft have seals that keep oil from leaking out and catching fire.
Since these rubber seals are exposed to high heat and oil, they wear out over time. They can’t do their job of sealing the engine any longer. When these seals break, oil will leak into the front of the engine and usually cause the oil to burn, which will make smoke or smells.
If there is a small leak in the crankshaft seal, oil may start to build up on the bottom of the engine. But if it’s a big leak, oil may leak out of the front of the engine and onto the ground. When the car is parked, you might notice the leak. If there are pools of oil under your parked car, you need to take it to a mechanic.
Use an oil that fights wear and deposits to cut down on engine oil use.
The best way to stop oil from being used up is to use a high-quality synthetic oil that is resistant to wear and deposits.
Over time, the oil keeps the piston rings from wearing out, so they can keep making a tight seal against the cylinder wall. It will also be better than regular oils at getting rid of deposits that cause rings to stick.
Here are some of the benefits to switch to AMSOIL Signature Series Motor Oils.
A New Level of Motor Oil Technology
Why AMSOIL? Superior protection against wear, improved fuel economy and better performance under extreme temperatures. AMSOIL is the only oil that is able to last up to 25,000 miles. Save yourself time and money and protect your car or truck by using AMSOIL products. Your vehicle will last longer and you will lower your maintenance expenses. Protect your Honda, Toyota, Nissan, Chevrolet, Ford, Chrysler or any other vehicle with AMSOIL synthetic oil!
We advise you to consult your owners manual for proper fluid recommendations and to consult the appropriate repair manual for proper maintenance procedures and specs. Follow all appropriate safety practices. We are not responsible for misuse of products.