overfilling engine oil

Overfilling Engine Oil: Will it damage my engine?

In Engine Oil by Magnus Sellén12 Comments

overfilling engine oilYour engine oil low light appears on your dashboard when you are in a hurry. 

You are purchasing 2 liters of engine oil and topping up your engine with it. You check your dipstick and realizing that you have overfilled the oil above the MAX sign on the dipstick.

What to do now? Will, it damages my engine if I keep driving with the level over the max?

In this article, you will learn what will happen if you are overfilling engine oil and learn what signs to look for.

Is it dangerous to drive with overfilled engine oil?

Overfilling your engine oil can cause serious damages to your engine. Some common symptoms are oil leaks from the engine and blue smoke from the exhaust pipe. If you have only filled a couple of millimeters above the max sign, there is no need to worry. But if you have filled a centimeter above the sign, it can cause severe damages to your engine.

overfilled engine oilThe engine oil reserve is designed to hold some extra oil to compensate for the fluid expansion which happens due to the hot condition. Adding an extra half a quart will not damage your engine. However, anything more than that could be harmful to the engine.

When you add too much oil, the excess oil will go towards the crankshaft, and as the crankshaft rotates at a high-speed, the oil is mixed with the air and ‘aerates’ or becomes foamy. This foamy texture of the oil acts like a bad lubricant, and as a result, the oil is not pumped effectively. Over the time, the engine will starve for proper lubrication, and due to the weak oil pump, it can get locked up.

Routine oil change is a part of car maintenance, and it should be done after every six months or 5,000 miles. Oil change is a relatively simple process and could be done at home as well. However, a small mistake can prove to be fatal for your car and could cost you hundreds of dollars. We are talking about overfilling the engine oil which can severely damage your car’s health, but we are here to explain to you how to tackle the situation.

Engine Oil Amount

Most of the engines require 5 to 8 quarts of oil, but it varies depending on the size of the engine. For example, a 4-cylinder unit will require 5 quarts of oil whereas a larger 6-cylinder engine may need approximately 6 quarts of oil. You can also find more information about your engine’s oil capacity in the owner’s manual. Always be careful that you fill the right amount.

Overfilled engine oil Symptoms

Sometimes you do not know if you or the mechanic have overfilled your engine oil. But if you have some of these symptoms, there might be a risk that your engine oil is overfilled.

  • Oil leakage
  • Burning smell of engine oil
  • Signs of smoke from the engine bay
  • Signs of smoke from the exhaust area
  • Engine making too much noise

Checking for Overfill

If you have noticed any of the above symptoms, it is likely that there is too much engine oil in reserve and steps should be taken to fix the problem. To ensure that there is excess oil, stop your car somewhere safe and shut off the engine. Open the hood and check the dipstick oil level to see the oil stain. Most probably it will be above the top marking indicating that excess oil is present.

Removing Excess Oil

Now that you are sure that the engine is filled with extra oil, it is time to drain the excess oil. There are two ways to do this: the first method is easy and less messy. It requires an oil suction pump through which you pull the oil from either the cap access point or the dipstick tube. This method does not require you to raise your car but will need an air supply for the vacuum. You can use both a manual vacuum pump or an automatic. If you want a manual tool for these tasks, and good for several other things. Check out the: Vacuum Fluid Extractor Pump Tank Remover Link to Amazon

The second method is a traditional one and can be messy as well. The tools required are a drive socket wrench and a plastic oil pan. Raise your car to some height then crawl underneath and locate the plug. Place the plastic oil pan beneath the oil plug and loosen the plug until the oil begins to drip. Make sure you don’t loosen the plug too much and remove only a certain amount. Check again with the dipstick to ensure the oil is of right amount.

Note: Some vehicles do have a cover under the car that has to be removed before you can reach the oil plug.

Post Maintenance Tips

Now that you know how important it is to keep the engine oil at its optimal level make sure to double check every time you take your car for the routine oil change. The recommended oil change schedule and the amount of oil your car engine need is mentioned in the owner’s manual. Sometimes if you had your car at a bad workshop, they might only fill the amount of oil from the information they got from their computer. Because of that, even a mechanic can make a mistake and forgot to check the oil level after a service. That’s why you should always double check after you or your mechanic have filled oil in your engine.

Conclusion

  • Overfilling your engine oil can hurt your engine and damage a lot of parts in your engine.
  • Be careful when you are filling your engine oil that you got the right amount of oil.
  • Always double check, even after your car have been in a workshop. They can make mistakes also
  • If you have some of the symptoms above, double check your oil dipstick

If you have any other questions about overfilling your engine oil, comment down below. If you have any other car questions, you are welcome to ask us at our homepage.

Hello I'm Magnus, the owner and the writer of this website. I have been working with cars since I was 16 and I'm specialized with in-depth Automotive diagnostics. Also been driving drifting for the last 6 years. I'm here to give you answers to all your automotive questions and I hope that you enjoy our content.

Comments
  1. i got my 1985 v8 rv servised oil was over filled. drove 800 hundred km never noticed any problems should i worry.

    1. thanks alot this tip has helped me solve the same peoblem

  2. I over filled engine oil never notice untill started to make a noise and vibrate

    1. Author

      It all depends on how much you overfilled it with. However if it does make noise and vibrate there is a risk that any internal of the engine got damaged.

      You have to drain the oil again and fill it with the required amount and check if the noise is gone. If it still occur, I would recommend you let a mechanic listen to the engine before driving it, which could cause even more damages.

      1. I realised that excess engine oil poured into the engine of my car after driving of 40 km.

        In between the car was stopped several times first time after running of 15 km.
        2nd time stopped the car after running of next 15km.
        Then stopped after running of 7 km, then after 5km
        Then every km.and I stopped the car.
        After a great deal of thinking I could realised that excess engine oil poured into my car by the service station.
        After that I communicated with the mechanic about the matter.
        But the mechanic replied that excess engine oil is not the reason of stopping of engine, and it will not cause any problems in car.

        But I did not believe his reply.

        I drained the excess quantam of engine oil.

        The problem is now improved but sometimes my said car stops while the car start after in the middle of running (when the engine is being running) to maintain traffic.
        On that time I feel that the engine is not getting fuel,
        I changed the fuel filter also. But nothing changes

        Kindly help by giving me what types of repairs can be done to running smoothly.

  3. I want to add a pint of STP oil treatment to my engine but I just had oil changed and not sure if that would overfill engine. I have a 2012 Lincoln MKZ with only 54000 miles on it.

    1. at only 54000 miles i would certainly not bother with STP as long as you used the recommended oil for your car it’s fine.

  4. I own a 2015 Mazda 6 Sport. I accidentally overfilled it with about 2 1/2 quarts of oil.
    I knew it was not good. I decided to drive 20 miles to my mechanic and on the way while on tbe freeway my sputtered a bit and made clanging noise. I noticed a cloud of white smoke. I pulled over and called AAA.
    While on the phone I decided to see if engine started. To my surprise it started with no problem or noise.
    I made it to my .echanice and hedrained my oil and added new oil.
    Car ran great on my route back. I had make anotber trip a little later and wbilemaming a right turn onto a slight grade my car once again sputtered and let out a cloud of white smoke. But it once again continued to run great afterwards.
    Is there a chance my engine can have damage?

  5. I drove my Mazda 6 20 miles after accidentally overfilling with 2 1/2 quarts of oil over limit.
    It sputtered and blew a cloud of white smoke . I pulled over and restarted engine with no problem. My mechanic drained the oil and replaced filter and it ran great. Noights came on but do I still have worry about engine damage?

  6. I noticed that the newer Volvos have eliminated the oil dipstick. With so much at stake for overfilling, why would the engineers get rid of this “analog” measurement? How did they replace its function?

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