5 Reasons Your Engine Oil Might Be Leaking

By Guest Author - April 3rd 2017

oil leak
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Have you gone out to the garage and found an oil stain where your car normally sits? This isn't just a nuisance to clean up; it indicates an oil leak. Oil serves as a lubricant for your engine and running low can cause irreversible damage. There are many factors that can cause your engine to leak oil, and it’s important to find a mechanic who can properly diagnose the issue. Here are a few reasons why cars leak oil.

1. The Oil Filter Was Attached Incorrectly

When getting an oil filter changed, the technician will make sure your car is fitted with the correct type and size. If the filter isn't attached properly, it could be a potential cause of a leak. If fitted incorrectly, it will most likely blow out while you are driving. Take it back to the shop where the oil filter was replaced for repairs.

2. The Oil Pan Is Damaged

A damaged oil pan causing a leak would require the oil pan to be fully replaced. The oil pan is on the bottom of the engine, so any oil leaks from the top or front of the engine could drain down and look like an oil pan leak. It's important to verify that there are no other leaks before having the oil pan resealed.

3. The Valve Cover Gasket Is Damaged

As your car ages and gains mileage, the gaskets can wear down. A buildup of sludge will add to the wear and tear, leading to oil leaks. These can be 'seeps' that cause you to smell oil as it falls on the hot engine, but you may not necessarily see drip marks on the ground.

An aged valve cover gasket can be a quick, visible answer when looking for the cause of an oil leak. When replacing the valve cover gasket, but sure to use high-quality parts. Occasionally, silicone will also be used to seal the area and ensure the leak doesn't continue.

4. The O-Ring On The Distributor Has Worn Down

On the off-chance you're driving a much older vehicle with an oil leak, the potential cause could be the O-ring on the distributor. This is less common, but over time, the O-ring wears down and can lead to leaks at the base of the distributor. It will also reduce the power, acceleration, and economy of the car, seriously affecting the drivability.

5. The Rear Main Seal Wears Down

The rear main seal keeps oil from escaping before it reaches the crankshaft. Running the engine on low oil can dry out the rubber and cause it to crack. This can also be caused by the simple aging of a vehicle. The rear main seal should be replaced regularly.

If you see yellowish brown or dark brown oil leaking out of your car, your car is using oil faster than usual, or your oil level is low, you should take your car to a repair shop as soon as possible. Keep you and your passengers safe by getting oil leaks diagnosed correctly and fixed by a RepairPal Certified shop.

RepairPal is working to mend the lack of trust consumers have in the car repair industry by providing them with in-depth knowledge and resources that connect them with dependable and reliable car repair shops near them.

Our goal is to establish an auto repair process that is less stressful and much more trustworthy for everyone involved. Our website hosts a car repair Estimator that gets rid of that "ripped-off" feeling. We also provide matches to local Certified shops that are guaranteed to do repairs with quality parts, a fair price, and a trained, awesome staff.

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2 User Comments

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The newer cars don't have the good old dipstick. These have electronics to tell you if you are low on oil. But what happens if there is too much oil? It would tend to create more pressure and try to leak out from somewhere. I believe my car needs about 6.5 quarts of when replacing oil and filter. But I am charged for as much as 8 quarts, when I question it, the shop says this is how much was added, because their "manual" says that. Is this action of more oil causing more damage to my car?