Used oil analysis helps diagnose problems before they ruin your engine
If motor oil is the lifeblood of an engine, then it makes sense to monitor this vital fluid’s condition. Used oil analysis reveals how oil changes over time, and provides data related to engine wear. In addition, a used oil sample properly drawn and analyzed may let a fleet manager extend oil drains with confidence.
According to Champion Laboratories Inc., which markets the Luber-finer brand of filtration products, there are three main reasons to do used oil analysis. The first is to indicate the level of physical engine wear, because analysis will show the metal content in the oil.
Second, used-oil analysis reveals the chemical level in the oil, which indicates the extent the oil is breaking down during use. Changes in the chemistry of used oil flag changes in the engine operation while also providing a way to track wear trends.
Third, in an enhanced exhaust gas recirculation (EGR) engine, soot levels can accelerate engine wear. “An excessive amount of soot in the oil will indicate that other engine systems may not be operating properly,” says Brent Birch, lab manager for Luber-finer.
Improving performance
Used oil analysis can help fleets improve engine performance since it tracks wear. “Every engine exhibits its own unique wear characteristics,” explains John Gaither, Luber-finer’s vice president of engineering. He goes on to say that analysis of each engine’s used oil provides a better idea when a truck engine may need to be replaced. Used oil analysis also lets fleet managers know which types and brands of engines perform better in their specific applications.
Brian Tucker, engine liquid product manager, Donaldson Co. Inc., says used oil analysis is a key component to extending oil drain intervals. It allows users to determine effective drain intervals without risking damage to equipment. “By performing regular oil analysis, you can monitor the health of the oil and change based on oil condition,” he notes. By using oil analysis and changing oil based on its condition, he says a fleet can increase vehicle uptime, equipment life, improve reliability, reduce operating costs and realize increased equipment resale.
Dan Arcy, technical marketing manager, Shell Lubricants, notes, “With used oil analysis, you’re developing a trend for that type of vehicle.” He explains that the same engine model used in on-highway applications will show different results in stop-and-go use. The difference in the numbers between two identical engines is less important than if there is a change in one engine in the same service over time.
Additionally, used oil analysis provides information to help determine whether the proper oil is being used and whether the proper oil drain interval is being maintained for specific driving conditions and the vehicle’s duty cycle. “If you decided, based on oil analysis, that 25,000 miles was the optimum drain interval, then if idling time, fuel economy or load size change, you may have to change your interval,” Arcy explains. “If you’re under heavier loads, you may be generating more soot, and you’ll detect that through higher soot levels in the oil.”
Shell LubeAnalyst oil condition monitoring provides customers with analysis to help assess the general condition of diesel engines and other vehicle components based on wear particles and other contaminants present in the oil sample.
How you take the oil sample can affect the accuracy of the analysis, says Arcy. To get good results train technicians to follow the same procedure each time. “Be consistent; always pull the sample the same way,” Arcy advises, “to get the best results possible.”
Results may show contamination. Generally , there are two types of oil contaminants: organic, carbon-based compounds (soot, unburned fuel, fuel resins and deposits) that together make up sludge, and inorganic contaminants (dirt, wear metals, gasket material, core sand and soot), which are responsible for most of the wear.
Engine wear from pistons, cylinders, valves, crankshaft, bearings, bushings, thrust washers, compression rings, liners, oil cooler, clutches, cooling systems and oil additives yield contaminants such as aluminum, iron, copper, chromium, lead and tin. If the oil’s chemistry or viscosity changes, coolant or water may be leaking into the engine.
Extending engine life
According to Dave Kunkel, marketing and direct sales manager for Citgo Petroleum Co., a combination of oil analysis software and the right lubrication solutions are all critical to extending oil drain intervals. Citgo’s HD LubeAlert is a website that fleets can use to submit and track data. Its unit condition report only lists units with current or potential problems and identifies which units were not sampled on schedule. Data is customized to each unit’s engine type and graphically illustrates oil condition trends and equipment wear, highlighting where parts erosion or oil contamination may exist.
Citgo has integrated LubeAlert into its HD Greenway program, a family of synthetic products and the company’s LubeAlert oil analysis management tool. The Greenway program is tailored for each fleet to pinpoint areas of savings.
John G. Eleftherakis, vice president – global technology, SPX Filtran’s DoubleDuty filtration product team, says, “Oil analysis is critical for monitoring and maintaining vehicles, but if a fleet doesn’t use information from the lab to bring its oil to the point where it needs changing, they’re throwing away good oil.”
SPX Filtran, which offers oil analysis under the OilTracker brand, provides reports that not only flag urgent problems and serve as vehicle performance references, but also allows filtration assessment, adds Eleftherakis. The company’s flagship filtration product, the DoubleDuty diesel engine spin-on lube oil filter, is a direct replacement for OE full-flow filters with the addition of one drain line back to an existing engine port. It offers the benefits of a full bypass unit. To remove the smallest particles without dropping the pressure flow, the DoubleDuty filter pulls a liter-per-minute of oil from the total volume and puts it through a high-efficiency bypass media element inside the full-flow OE-size housing to achieve 99.9 percent efficiency at 4-micron size. With reduced particulates and slowed oil degradation, drains can be at least doubled. Skipping every other oil change –– maybe two per year –– based on an average of four per year for an over-the-road truck, saves twice the volume of engine oil, cost of a filter, labor and disposal, which calculates at $100-$500 per truck per year, Eleftherakis says.
A diagnostic tool
Consider used oil analysis as a diagnostic tool. Kenneth Claar, senior field test engineer for the Lubrizol Corp., an additive supplier for the lube oil industry, advises fleets to refer to the Technology and Maintenance Council’s (TMC) Recommended Practices (RP 334A), “Guidelines for Establishing Proper Engine Oil Drain Intervals for Heavy-Duty Diesels” and RP 318B, “Used Engine Oil Analysis,” which he notes is being updated. Claar also says heavy-duty fleets will find value in RP 1403, “Determining Engine Oil Change Intervals for Light- and Medium-Duty Vehicles” and RP 1420(T), “Fluid Analysis for Class 2-6 Vehicles,” proposed last December.
When doing used oil analysis, look at the results, he cautions. Go beyond looking for abnormal readings, plot data and look for trends. If there are changes, find out if they are due to changes in duty cycles or load factors.
With the price of fuel, oil and labor, fleets need to analyze used oil. If this practice prevents just one engine failure, oil analysis will have more than paid for itself.
“Don’t just look at individual reports, check the whole database,” advises Mark Minges, chief operating officer of Polaris Laboratories LLC. “That will show where maintenance practices need beefing up and answer why you may be having a specific problem.”
Work with the used oil analysis laboratories. They can provide recommendations as to when lubricants and filters should be changed and maintenance performed to protect and extend the life of the vehicle. Take the action recommended, then report back to the laboratory what was done to correct the problem.
“We try to compare one fleet’s statistics with others in their industry,” Minges continues. “Most are shocked to learn their results are worse than other, similar fleets. They find value in the program and continue, not just for what it reveals about an individual unit, but for the whole operation.”
Where warranty issues are concerned, oil analysis benefits the fleet as well as the OEM. It’s always in the OEM’s best interest to pay a warranty claim on a relatively minor event rather than one on a catastrophic failure, Minges says. “It’s in everyone’s best interest to catch a problem at the earliest stage possible.”
Failure prevention
Russ T. Bretell, director – global customer education for Cummins Filtration, says used oil analysis is more than a diagnostic tool; it can detect and prevent catastrophe. “There’s a sense that you’re not getting your money’s worth when nothing shows up,” he explains, “but the real value comes when something does happen and you know before a failure.” Customers have said they used to do oil analysis but quit because it never told them anything. Bretell responds, “Oil analysis is like a blood test –– you don’t want to hear any bad news. You want to learn everything is fine.”
If a fleet goes to an extended oil drain program, a quality extended-service filter that lasts as long as the oil should be used. Cummins Filtration offers Fleetguard extended filtration products for this purpose. “The correct oil drain interval nets the customer the lowest cost of operation, and you get there through oil analysis, Bretell says. “Go too long and engine problems will start to occur; go too short and you’re throwing away oil too soon, which adds labor and disposal costs.”
Lifeblood
Wix oil filtration experts state that oil is the lifeblood of any vehicle, and they say this holds particularly true of heavy-duty fleet equipment. The biggest risk to fleet engines is taking oil filtration for granted. However, this small and inexpensive portion of the overall system plays a vital role in protecting engines from premature wear and potential failures.
Technicians should choose oil filters designed specifically for the demanding work their engines are expected to perform. Here’s what technicians should look for:
Heavy-duty oil filters should be made of high-quality materials designed to resist all fluid types, vibration and high and low temperatures in order to maintain consistent and reliable performance. Wix says its heavy-duty oil filters are “prescription engineered” to perform under all operating conditions.
The inner elements of heavy-duty oil filters are exposed to a wide variety of fluctuations in flow and pressure. Wix HD oil filters are purposely “over-engineered” for these reasons and to assure overall system protection, the company says.
The most important internal component for heavy-duty oil filters is the filtration media. Filter media should provide the correct balance of efficiency and capacity in order to deliver the required flow for proper lubrication, the level of filtration needed to protect your engine from contaminants, and the endurance to exceed standard maintenance intervals.
OIL SAMPLING TIPS
Daryl Riley, Donaldson Co. Inc.’s manager of field service, offers these tips for successful oil sampling:
1. Take a hot sample only after 15 minutes of engine operation.
2. Clean the sampling area where you insert the probe or sampling tube.
3. Take a purge sample and dispose of it.
4. Use a clean container to take the lab sample
5. Apply a properly completed label to the container.
6. Send sample to be analyzed in a timely manner – don’t let it sit around a few weeks.
More helpful explanations are to be found in TMC RP 318B “Used Engine Oil Analysis” and TMC RP 1417 “Lubricant and Fluid Sampling Guidelines.”
