Trucking, Leroy Dean & Company, we can show you how easy it is to implement a contamination control program.

development in motor oil contamination removal. Even if you're not maintaining a large diesel truck, the benefits of bypass filtration are still extremely important. The following article is reproduced here with permission of Tom Gelinas, the author of the article, publisher of Fleet Equipment Magazine.

by Tom Gelinas
(reprinted with permission)

The advice found in the adage "If a little is good, a lot must be better" doesn't apply too often. It most certainly does, however, when it comes to lube oil filtration---If you do the filtering properly.

Simply adding more filters, or finer filters is not always the way to achieve better results. Caterpillar advises "Each engine manufacturer designs a lubrication system to handle the dirt and contamination generated by that specific engine." Some engines have different needs than others. Filter out too much, and the filter will plug. Filter out too little, and engine wear will increase.

Filters are important!!!

While base oil does not wear out, the various additives in the oil become depleted due to contamination and particles. And when the additives are gone, the oil will no longer perform effectively. Filters play an important role in how long you can count on your oil to do its job. Proper filtering prevents buildup of contaminants that can score bearings, rings, and cylinder walls of the engine. Contaminants can also contribute to an increase in viscosity and gum deposits on rings and valves.

Because filtration is necessary for effective engine protection, it is important to make sure you have the best available system in good working order. According to trucking experts, 60 percent of the potential causes of wear and failure can be eliminated by well-designed and properly applied filtration systems.

When using a bypass filter system, an acceptable system is "one that saves you two or three oil changes by removing wear causing particles that eat up your engine internals. Wear is caused by having particles of dirt suspended in the oil that are bigger than the film of oil between moving parts when the equipment is under load."

You have a choice.

Early diesel engines used a bypass filter exclusively, according to Cummins Engine Co. A bypass filter has a relatively high-pressure differential and usually flows only about 10 percent of the total pump output. It is called bypass because the oil flows back to the sump, bypassing the engine itself. The high pressure differential across a bypass filter causes the oil to flow very slowly through it, allowing the fine filtration to clean the oil and leave the contaminant in the filter, not the engine.

In the early 1960's, a move away from the use of bypass filters was made by some engine manufacturers. Full flow filtering systems grew in popularity. Such systems handle the entire pump output, and are designed to filter out relatively large particles only---those in the 40 to 60 micron range. A full flow filter has a low-pressure differential across it, and is placed between the oil pump and bearings or other location being lubricated, It provides a very useful function because it removes particles on a continuous basis.

Like some other engine suppliers, Cummins recommends that both bypass and full flow filters be used. With both systems being used it provides the lowest overall user cost because of the double protection against wear. The combination protects engines from catastrophic events by filtering all lubricant flowing through the system. Very fine abrasive particles also are removed by the bypass filter.

Testing supports bypass systems.

Studies at Cummins Technical Center using various size contaminant particles in an unfiltered NTC 335 engine indicated that particles above 5 microns cause the most wear problems. This suggests that a filtering system removing particles in the five micron and smaller range could minimize bearing and ring wear. "These particles are indeed removed by the bypass filter, not by the flow filter alone." Results of the test with various systems were also performed. The data was obtained by adding fine test dust samples to an engine sump and checking various filtration systems. These studies indicate that wear can be reduced by up to 91 percent as a result of using a bypass filter in combination with a full-flow design.

Another study was made using dump trucks under normal operating conditions. Of course, no dirt was added to the oil sumps for this test. The test vehicles, each having a 40 micron full-flow filter, were run 120,000 miles, and subjected to normal maintenance procedures. Test results show that piston ring wear was reduced 63 percent and bearing wear 30 to 64 percent as a result of adding a bypass filter.

Filter Maintenance.

In answer to the question "Does an engines age affect the filter?" Caterpillar says, "Yes." For example, as an engine ages more and more, blow-by compression gas passes into the crankcase. This gas carries carbon from combustion, which is removed by the filter. The older the engine gets, the more carbon must be removed. (Don't put off adding a bypass filter because the engine has higher miles, this is when the engine needs added protection the most.)

Particulate contaminants entering through a leak near the air filter not only wear out the rings and increase blow-by, but they also enter the lubrication system and plug the filter. By using oil analysis, this is picked up very quickly, testing your oil is must when determining problems inside the engine.

Yes, a little filtration is not only good, but imperative. And, yes more filtration is indeed better, but only if it's done properly.