Most of us are comfortable doing things the way they’ve been done before and we tend to stick to our methods, regardless of whether the method is logical, but because "we’ve always done it that way." Take for example, changing oil.
Many of you while reading this are thinking, “I need to get my car in for an oil change”. And how often do you change your oil in your car or truck? Whether or not we adhere to a predetermined interval, most of us know the "every 3,000-5,000 miles or 6 months, whichever comes first" criteria. I’m sure you’ve been told that changing our car’s oil is the single most important maintenance procedure you can do to prolong the life of the engine.
The formula in the Operation and Maintenance Manuals for changing the oil in your Generator is similar: every x hours of running time (instead of miles), or at a year’s interval, whichever comes first.
Have you ever wondered about this "standard"? Oil goes "bad" – in two ways: first, simply running an engine will deteriorate lubricating properties, and second, time itself will cause the oil to degrade. So, how does oil actually lose its lubricating properties? Before I answer that all important question, it is important to understand what the function of oil actually is. Simply, the reason for oil in an engine is to keep the metal parts from rubbing together. When oil begins to lose its lubricating properties, the metal parts under stress within the engine begin to rub together. Hence, internal damage begins.
One way that oil structure can change is through oxidation and the depletion of additives – but this happens very slowly. Oil also can become contaminated through the presence of impurities that diminish the protective properties. These impurities can be liquids like water and fuel or particulate matter including dirt and inbuilt metals.
Engine manufacturers assume that impurities will appear in the lubricating system sooner or later and that oil changes are inevitable. The question of when that unavoidable oil change should be done is one that needs to be asked – do we do it sooner – or later? You would think that it should be done when the oil is shown to contain impurities. But how do you know if there are impurities in your oil. To that, many don’t have an answer.
The only way to know if your oil has contamination is to sample it and oil should always be sampled just before changing it. Through the process of sampling (or testing), you should receive an oil analysis report. An analysis report contains information about your engine and with each oil analysis, you can begin to build a trending program and this can be an indispensable tool for predictive maintenance. A series of these reports over time will provide invaluable information about trends taking place within the engine. Not only can an analysis measure changes caused by the presence of soot, oxidation, fuel, glycol or water, and even the depletion of necessary additives, a more detailed analysis can identify and measure metallic elements present in the oil as microscopic particles.
Information contained in your analysis trending program can indicate if the contaminants are high enough to necessitate an immediate oil change and repair or if specific internal engine components are wearing based on the metals and alloys in the oil.
Oil change intervals are both a matter of time and of tracking the condition of the oil. Therefore, changing the oil in your power generator engine can be systematic or analytical, or both. Adoption of these methods can keep your Emergency Power System ready to do its job when you need it most.
Michael Bonville
Power Generator Specialist
Training Administrator