Four most common gasket oil leak locations

There are four common engine locations where gasket oil leaks are most likely to occur. Knowing where the engine is leaking oil can help a technician diagnose the underlying problems to avoid major damage and costly repairs down the road.

To help you determine the source of an oil leak, and how to treat it, here’s a list of the most common gasket locations of engine oil leaks:

1. Oil filter gasket. Leaks occur when the filter isn’t adequately tightened or if it loosens over time. Usually it’s simply a matter of tightening the filter to the manufacturer’s specifications, typically printed on the side of the filter. If the old filter needs to be changed, make sure the mating surface is clean, and the old gasket is completely removed.
2. Oil pan gasket. This gasket between the pan and the engine block is subject to different stresses such as pressure, thermal expansion and vibrations can cause oil pan gaskets to leak. The bolts can also loosen over time, allowing oil to seep out. A quick check of the bolt torque on the oil pan can often be all it takes to stop an oil pan engine oil leak.
3. Oil pump gasket. Some engines have an external oil pump attached to the engine block with bolts and a gasket that can wear out and leak. Insufficient oil in the oil pump can cause premature wear to the pump and oil starvation to the engine, leading to further — and possibly major — damage. Verify the oil pump bolts are adequately tightened.
4. Rocker cover gasket. The valve train of an engine is covered with a rocker or valve cover, one cover for an inline engine or two for a V-style engine. A gasket between the cover and cylinder head keeps the engine oil from leaking out. Oil leaks at this location are relatively common, especially in older vehicles. Verify the rocker cover bolts are adequately tightened.

If these suggestions don’t stop the leak, often it’s a gasket problem. Different types of gaskets — rubber, cork, silicone or liquid sealants — are used as OEM and replacement solutions, but all are susceptible to leaks after years of use. They shrink, harden or crack due to age, high mileage or extended vehicle storage.

Replacing gaskets can be a tricky, time-consuming and expensive undertaking. By repairing these seals instead of replacing them, you can save time and money. If the cost of a physical repair is not within the budget, a bottle of one of Bar’s Leaks stop oil leak products: Rear Main Seal Repair (p/n 1040), Engine Stop Leak Concentrate (p/n1010), Engine Repair (p/n 1000), Oil Seal Engine Oil Burning & Leak Repair (p/n OS-1), or One Seal Stop Leak (p/n 1334) will stop a gasket oil leak permanently, Bar's Leak says.

Information provides by Bar's Leak.