5 Benefits of an Engine Flush

Sometimes, the way we drive keeps engine oil from being able to do its job completely and well. Short trips of only a few miles and lots of stop-and-go driving can cause particles in the oil to become deposits in the engine, which can build up over time. These deposits restrict the flow of oil.

An engine flush can clear out those deposits to open narrow oil passages clogged by gunk that's been floating around in the oil. Releasing those deposits and allowing the oil to flow freely saves wear and tear on the engine and keeps parts moving as they should.

While most cars that are driven and maintained regularly don't need an engine flush, there are a few cases where doing an engine flush may help:

Cars with an unknown maintenance record. If you just bought an older used car for a great price but it didn't come with any maintenance records, an engine flush followed by a few quarts of fresh oil might save you a headache later.

Cars with recent internal engine work. You know the maintenance record of this engine -- and it's major. If your car had any engine work done, an engine flush could wash away leftover particulates before adding new oil.

Cars with a long interval between oil changes. Again, you know the service record of this car, and you know the owner rarely (if ever) changed the oil. There's almost certainly buildup in the engine, since dirty oil only gets dirtier. An engine flush could give the car a longer life.

Especially if you recognize your car's history (or lack of history) on the previous page, an engine flush could help keep your new oil clean. That's why these services are often performed together: First the flush to get rid of old oil deposits, then the new oil to keep the engine in tip-top shape.

Without the engine flush, the new oil will just pick up the old deposits and sludge and keep them circulating through the engine. Soon enough, the new oil is just as dirty as the old oil. An engine flush can help you go longer between oil changes, especially if the maintenance on the car hasn't been perfect.

Most oil filters remove particles as small as 25 microns (about 1/1000th of an inch) -- but there are particles circulating in your car's oil that are even smaller -- particles that even the newest, best filter can't keep out of the system. And even tiny little bits like that can cause wear over time. They can also band together to create sludge and deposits.

If these particles become excessive, clean oil alone can't flush them out. But the chemicals used in an engine flush can -- stopping any further wear and giving the new oil a chance to do its job properly.

If the gunk in the engine oil gets too bad, the parts of the engine can get gummed up. An engine flush removes the gunk, which keeps the parts running smoothly. That in turn can make the engine more efficient, bringing the power and fuel efficiency closer to what the car had when it left the showroom floor.

In very old cars, however, the engine flush might clean these piston rings, valves, and other parts a little too well. Sometimes, the gunk acts as spackle in non-metallic parts like rubber seals that have cracked with age. Cleaning out the gunk exposes those cracks, and the weakness of those parts becomes apparent.

For more information about engine flushing and other related topics, follow the links on the next page.