How to Remove Engine Oil Sludge

by Jessica Jewell

Engine oil sludge can build up in the engine's valve cover and oil pan, blocking the oil screen siphon and resulting in engine failure. The buildup is difficult to diagnose because a blockage may not affect the oil level. As the oil becomes sludge, it reduceslubrication, which causes increased friction and damage to the engine. Fortunately, by changing the oil from conventional oil to synthetic oil, and correctly flushing the engine, you can remove engine oil sludge.

Exchange the oil filter for a new filter and pour in a high-quality engine oil flush to 10 percent of the oil capacity. You can check the capacity with the dipstick.

Turn on the engine and allow the car to idle for 20 minutes, then turn the car off again.

Place a drain pan underneath the oil pan and unscrew the oil plug. The old oil and flush will drain out of the oil pan and into the drain pan. Once all of the old oil and flush have drained, reattach the oil plug.

Fill the engine's crankcase with high-quality synthetic motor oil that meets the requirements of your particular vehicle. Your car manual should indicate what type of motor oil is best suited for the car but if you are unsure, just ask an associate at an auto store where you purchase the oil. You want to purchase a high-quality synthetic oil that resists oxidation and has good dispersant properties, so that your engine won't develop any other sludge problems.


  • Do not flush the transmission, differentials, or engines that are air-cooled or share a common oil sump with the transmission. Also, do not flush an engine that doesn't have an oil filter.

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About the Author

Jessica Jewell is a writer, photographer and communications consultant who began writing professionally in 2005. Her chapbook, "Slap Leather," is forthcoming from dancing girl press. Her recent work has appeared in "Nimrod," "Harpur Palate," "Copper Nickel," "Rhino," "wicked alice," "Poetry Midwest" and "Barn Owl Review." Jewell was recently nominated for a Pushcart Prize. She earned her Master of Fine Arts from Kent State University.

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