Oil Filter – A Dirty Oil Filter, Will Obstruct The Flow, Of Clean Oil

Oil Filter - A Dirty Oil Filter, Will Obstruct The Flow, Of Clean Engine Oil
Oil Filter - A Dirty Oil Filter, Will Obstruct The Flow, Of Clean Engine Oil

Your typical oil filter has to perform, a crucially important job.

The oil filter removes, solid contaminants, such as dirt, carbon and metal particles from the engine; before they can damage, bearings and cylinder wall surfaces in the engine.

Consequently, most filters do a good job, but after a few thousand miles on the road; they will start to degrade, from overuse. So, one of the biggest challenges that the oil filter has is to cope with today, is longer service life.

Above all, always use the oil filter recommended for your vehicle. Some filters may filter out, smaller bits of dirt a little better, and some may last longer.

OEM-recommended oil change intervals, for “normal” driving today, can range from 5,000 to 7,500 miles. Many vehicles don’t even have, a recommended service interval and rely instead, on a “Service Reminder Light”.

Oil Filter
Oil Filter

On some vehicles, the light may not come on, for 12,000 to 15,000 miles, depending on driving conditions! That’s a long time for filters, to remain in service. So, make sure that you change your oil and filter, on a regular basis.

Because, the development of engine sludge is directly related, to how often you change your oil.

With Full-Flow Filtration, the oil is cleaned, before it gets to the:

  • Crankshaft Bearings
  • Cam Bearings
  • Valvetrain

As a result, it is an efficient way, of removing contaminants and it assures; only clean oil is supplied to the engine. In time, though, accumulated dirt and debris, trapped by the filter; begin to obstruct the flow of oil. Since there is no way to tell how dirty the filter actually is; the filter should be changed, according to the maintenance schedule; in your vehicle owner’s manual.

Dirty Oil Filter
Dirty Oil Filter

Though some vehicle owner’s manuals say replacement at, every other oil change is acceptable; most professional technicians, always change both at the same time.

So, why contaminate the clean oil, with up to a quart of dirty oil. And, why risk expensive engine damage, if the old one is on the verge of clogging up. In addition, a new one is cheap insurance against, premature engine wear.

Oil Filter Bypass Valve

To prevent a clogged filter from starving the engine for lubrication; filters have a built-in safety device.

Bypass Valve
Bypass Valve

When the differential pressure across the filters element exceeds a predetermined value, (which varies depending on the engine application); the bypass valve opens, so oil can continue to flow to the engine.

However, when the bypass valve is open, no filtration occurs. The bypass valve also opens, when a cold engine is first started. Because, cold oil can be fairly thick and may not pass through the filter element very easily.

So, the bypass valve opens and allows the oil to go around the filter; until the oil warms up. Then, contaminants that are in the crankcase, bypass the filter. Consequently, causing increased engine wear and possibly engine damage. However, once the oil gets warm and the bypass valve closes; oil flows through the filter and normal filtration resumes.

Furthermore, there is no warning sign, like a change in oil pressure. Because, the oil will just bypass the filter.

So, most filters look alike on the outside. But, all are NOT all the same.

Some manufactures, for the same application, may or may not include, an anti-drain back valve in their filter. This valve basically, stops oil from draining out of the filter, after the engine is idle. As a result, helping with dry starts !

All Filters Are Not The Same
All Filters Are Not The Same

There can be significant differences, that affect both filtration efficiency and longevity. Consequently, some may contain up to, 50% more square inches of filter media than, a cheaply made filter.

So, which one would you rather have on your engine? One with increased filtering capacity or one that may not go the distance?


Consequently, a new filter is far less expensive, than a new engine. In addition, dirty or clogged filters, allow contaminants, to sail straight to your engine; where they can cause damage. Finally, you also risk blocking the flow of oil to your engine; which could result in engine failure.

Thank You !