Filtration and Condition-based Maintenance Can Save an Engine

Are oil-change intervals on your truck a concern of yours? If not, then surely avoiding a major engine failure is.

Nichols Concrete Equipment has a long tradition of pumping concrete, but when times are tough, they do not sit with their hands in their lap and wait. Instead, they think smart and focus on maintenance costs because they know that sometimes you need to spend a little now in order to create large savings in the future.

Nichols has 18 concrete boom and line pumps at its site in Pelham, Ala., and a total of 55 trucks at its five service centers. They all run the same Mack AI ASET engine and transmission, but the rest of the trucks vary. The largest seven-axle truck has a boom of 61 meters (200 feet).

Ben Schlichter stands in front of a Nichols’ boom truck fitted with a CJC filter.

"The oil systems on the cement trucks are working under severe conditions,” says service manager Bernd “Ben” Schlichter. “In 2008 we decided to start focusing on our maintenance costs, and we took a closer look at the engine lube oil. Of course, we changed the oil as recommended in the manual, but I believed there was a superior way to take care of the dust, wear particles and soot challenges than just changing the oil.”

A common misunderstanding is that oil needs to be changed after a fixed time, miles or hours in operation. The wiser strategy is condition-based maintenance (CBM), which means only changing the oil when an oil analysis says that you need to – and not due to contamination, because you can easily get the dust, wear particles, water and oil oxidation (varnish) under control by fitting a good-quality offline/kidney-loop filter.

Nichols worked with C.C. Jensen Inc. (CJC) to investigate its lube oil problems. Prior to looking at the engine lube oil, they worked on hydraulics, installing kidney-loop filters that showed good results keeping particulate and water levels down, which resulted in better performance and longer component life.

Specific to engine lube, it is advisable that an oil change should be based on the oil’s neutralization number (BN/AN), additive depletion, fuel dilution, soot level, oil viscosity out of specs or if the oil has been mixed with incompatible oils.

All of this can be checked with used oil analysis, which was exactly what was advised on the Mack engine lube oil. Instead of replacing the oil every 300 hours, an oil sample was taken and sent to a lab capable of reporting particle counts in ISO codes.

An offline filter was mounted on the frame of the cement truck. The filter draws oil from the bottom of the engine sump through a hollow drain plug and returns the polished oil back to the engine through the oil filler tube.

The CJC filter polishing the engine oil from the Mack engine.

Because the filter took care of the lube oil contaminants, Schlichter decided to test how long an oil change could be postponed. He took oil samples every 300 hours, and when the oil was still up to par, it remained in the engine. The same engine lube oil was in operation for 1,300 hours, and the properties were still intact, except for the soot level being high at 900 hours.  

Starting this condition-based monitoring program, Nichols Concrete Equipment confirmed how important oil analysis is for the reliability of the boom trucks.

“The oil sample taken at 900 hours showed an increase in soot (insolubles),” Schlichter says. “The filter was doing its best to keep up, but the soot level in the oil was abnormally high. We found that this soot problem was caused by an improper valve adjustment, so we fixed it.”

This photo shows the used CJC insert saturated with diesel engine soot compared to the new insert.

Meanwhile, on one of Nichols’ other boom pumps, a similar valve problem occurred.

“Unfortunately, we hadn’t fitted a CJC filter on this engine, nor did we do oil analysis, so the valve maladjustment got so bad that it caused severe engine damage,” Schlichter says. “If we had a CJC offline filter on this engine and had been watching the oil analysis just like we did on the one with the CJC filter installed, we could have avoided this engine failure, costing us $7,700 to repair. We have learned that condition-based maintenance is the way to go – not only because the engine lube oil will last much longer, meaning less oil waste, but also because it can save us from doing expensive engine overhauls.”

Used engine oil analysis results from Insight Services.

For more information on CJC offline filters, visit www.ccjensen.com