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Oil leaks are among the most common car maintenance concerns. If you’ve noticed a dark puddle under your car or the smell of burning oil, you’re likely asking, “Why is my car leaking oil?” An oil leak can have several causes, and addressing the issue promptly is crucial to protecting your engine and ensuring your car’s reliability. This article will explore the common reasons for oil leaks and how to fix them.
Reasons Why Your Car is Leaking Oil & How To Fix
Oil leaks can occur for various reasons, from worn-out components to simple maintenance issues. Understanding the cause of the leak and taking appropriate action can save you from costly repairs down the line.
Worn-out or Damaged Oil Pan Gasket
Cause:
The oil pan gasket seals the connection between the oil pan and the engine block. Over time, constant exposure to heat, vibrations, and oil pressure can cause the gasket material to degrade or crack, leading to oil leaks. These leaks are especially common in older vehicles or those that experience frequent stop-and-go driving, which increases engine strain.
Signs:
Visible oil pooling under your car.
A drop in oil levels on the dipstick.
Oil stains around the oil pan area.
Fix:
Replacing the oil pan gasket involves removing the oil pan, cleaning the surfaces to ensure a proper seal, and installing a new gasket with the correct torque specifications. While this task is manageable for experienced DIYers, it requires precision and the right tools. At McCullough NAPA Auto Care in Alpharetta, our technicians ensure the job is done efficiently and correctly, saving you time and hassle.
Degraded Valve Cover Gasket
Cause:
The valve cover gasket is responsible for sealing the area where the valve cover meets the cylinder head. Over time, exposure to heat and oil can cause this gasket to harden, shrink, or crack. This degradation often leads to oil seeping out, especially when the engine is running. It’s common in vehicles with high mileage or poor maintenance history.
Signs:
Oil leaking from the top of the engine.
A burnt oil smell in the cabin.
Oil accumulating near the spark plugs.
Fix:
Replacing the valve cover gasket involves removing the valve cover, cleaning the mating surfaces, and installing a new gasket with the correct sealant if needed. Professionals best handle this repair to ensure no debris enters the engine. McCullough NAPA Auto Care offers reliable valve cover gasket replacements to keep your engine running smoothly.
Loose or Worn-Out Oil Drain Plug
Cause:
The oil drain plug is located at the bottom of the oil pan and is removed during oil changes to drain old oil. Over time, this plug can loosen due to vibrations or become damaged, and its washer can degrade, leading to leaks. Improperly tightening the plug after an oil change is also a common cause of this issue.
Signs:
Oil dripping directly under the oil pan.
Fresh oil puddles after an oil change.
Fix:
Tightening the oil drain plug to the manufacturer’s specifications or replacing the washer often resolves the issue. If the plug itself is damaged, it can be replaced with a new one. While straightforward, this task requires care to avoid over-tightening, which could strip the threads. At McCullough NAPA Auto Care, we ensure your drain plug is secure and leak-free during every service.
Damaged or Improperly Installed Oil Filter
Cause:
The oil filter traps contaminants and debris in the engine oil. If the filter is damaged, improperly installed, or the gasket is not seated correctly, oil can leak out, especially when the engine is running. Using the wrong filter for your vehicle can also contribute to leaks.
Signs:
Leaking oil near the oil filter housing.
A noticeable drop in oil levels after an oil change.
Fix:
Replacing the oil filter with the correct model and installing it with proper torque can resolve the issue. Applying a thin layer of oil to the filter gasket before installation helps create a better seal. If you prefer professional assistance, McCullough NAPA Auto Care can quickly and correctly replace your oil filter during routine maintenance.
Cracked or Corroded Oil Pan
Cause:
The oil pan holds the engine’s oil supply and is exposed to road debris, moisture, and salt, which can cause cracks or corrosion over time. Accidental impacts with road hazards, such as speed bumps or rocks, can also damage the oil pan, leading to leaks.
Signs:
Visible damage to the oil pan.
Persistent oil pooling under the car.
Fix:
Minor cracks can sometimes be patched with epoxy or welding, depending on the severity. However, significant damage typically requires replacing the oil pan. This involves draining the oil, removing the damaged pan, and installing a new one with proper sealing. At McCullough NAPA Auto Care, our skilled technicians can efficiently inspect, repair, or replace your oil pan to restore your car’s performance.
Failed Rear Main Seal
Cause:
The rear main seal is located where the crankshaft exits the engine and connects to the transmission. This seal prevents oil from leaking out as the crankshaft rotates. Over time, heat, pressure, and age can cause the seal to wear out or crack, leading to substantial leaks. High-mileage vehicles are particularly prone to this issue.
Signs:
Oil dripping between the engine and transmission.
Large oil puddles under the car.
Fix:
Replacing the rear main seal is a complex and labor-intensive task. It involves separating the engine and transmission, which requires specialized tools and expertise. At McCullough NAPA Auto Care, our experienced technicians can efficiently handle this intricate repair, ensuring your vehicle is back on the road without further complications.
Faulty Camshaft or Crankshaft Seals
Cause:
The camshaft and crankshaft seals are critical for keeping oil contained within the engine while allowing these components to rotate smoothly. Over time, these seals can become brittle, shrink, or crack due to exposure to engine heat and contaminants. This can lead to oil escaping, often resulting in visible leaks or reduced oil levels.
Signs:
Leaks near the front or back of the engine.
Oil stains around the timing cover area.
Fix:
Replacing these seals requires partial engine disassembly to access the components. This type of repair is best performed by professionals, as incorrect installation can lead to further leaks. McCullough NAPA Auto Care’s skilled technicians can ensure the seals are replaced correctly, restoring your engine’s integrity.
Oil Filler Cap Issues
Cause:
The oil filler cap prevents oil from escaping the engine and contaminants from entering. A loose, damaged, or missing filler cap can cause oil to leak or spray out, particularly while the engine is running. Over time, the rubber gasket on the cap may degrade, reducing its ability to create a proper seal.
Signs:
Oil splatter near the top of the engine.
A noticeable oil smell after driving.
Fix:
In most cases, replacing or properly securing the oil filler cap resolves the issue. It’s an easy fix for car owners, but if you notice additional oil leakage, our team at McCullough NAPA Auto Care can inspect your engine to rule out other potential problems.
Overfilled Engine Oil
Cause:
Adding too much oil to your engine can create excessive pressure, causing seals and gaskets to fail. Overfilling can also lead to oil being forced into the crankcase ventilation system, resulting in leaks or smoke from the exhaust. This is often a result of misjudging oil levels during a refill or oil change.
Signs:
Oil leaks appearing after an oil change.
Increased smoke from the exhaust.
Fix:
The excess oil must be drained to the manufacturer’s recommended level to fix an overfilled engine. This simple procedure can prevent further damage. McCullough NAPA Auto Care can quickly adjust your oil levels and inspect your seals or gaskets for damage.
Blown Head Gasket
Cause:
The head gasket sits between the engine block and cylinder head, sealing the combustion chambers, coolant passages, and oil passages. A blown head gasket can occur due to overheating, engine stress, or improper maintenance. When the gasket fails, it can allow oil and coolant to mix or escape, leading to significant engine issues.
Signs:
White smoke from the exhaust.
Milky oil or coolant appearance.
Overheating engine.
Fix:
Replacing a blown head gasket is a major repair that involves disassembling parts of the engine to remove the faulty gasket and install a new one. It’s essential to address this issue promptly to avoid further engine damage. McCullough NAPA Auto Care’s ASE-certified technicians have the expertise to handle this repair, restoring your vehicle’s performance and reliability.
How To Identify an Oil Leak
Identifying an oil leak can save you time and money. Here are some tips:
Visual Signs: Look for dark brown or black puddles under your car. Engine oil is typically thicker and darker than other fluids.
Oil Smell: A burning oil smell while driving can indicate a leak in hot engine parts.
Dashboard Warning Light: The oil pressure or check engine light may signal low oil levels due to a leak.
Distinguishing Fluids: Oil is usually darker and slicker than other car fluids, like coolant (green or orange) or transmission fluid (red).
Why Addressing Oil Leaks is Crucial
Ignoring an oil leak can lead to:
Engine Damage: Low oil levels increase friction and heat, which can damage engine components.
Environmental Impact: Leaking oil contaminates soil and water, harming the environment.
Higher Repair Costs: Small leaks can become significant issues if left unaddressed.
Addressing oil leaks promptly keeps your car running efficiently and reduces the risk of costly repairs.
Schedule Your Appointment with McCullough NAPA To Stop Your Car’s Oil Leak
At McCullough NAPA Auto Care, we specialize in diagnosing and repairing oil leaks for drivers in Sandy Springs. Whether a simple fix or a more complex repair, our ASE-certified technicians have the experience and tools to do the job right.
Don’t let an oil leak compromise your car’s performance. Schedule your appointment to book your service. Let us help keep your vehicle running smoothly!