In extremely cold weather, poor combustion sealing can cause diesel engine lube oil to get past piston rings in the power assemblies and pushed out the exhaust stack. Locomotive mechanical officers call the condition “souping.” It’s a messy environmental problem, with oil-coated carbodies that need to be cleaned, at high labor and disposal costs.
In all weather conditions, incomplete combustion can cause another environmental problem: trackside fires lit by hot embers belching from locomotive exhaust stacks, not to mention soot buildup, with ash deposits and sludge accumulating in the prime-mover’s upper deck and airbox. Two years ago, an OmniTRAX short line in Washington State amassed $43,000 in state Department of Environmental Protection fines.
Two years ago, OmniTRAX, at the behest of Director Mechanical Services Troy Allen, began evaluating zMAX® micro-lubricant in about a dozen EMD GP38-2, GP39-3, GP40-2 and SD50 units. Today, the trackside fires in Washington State have disappeared, along with the DEP fines, and the oil-coated carbodies that were a common sight during Chicago’s “Arctic Blasts” of extreme cold are clean (below, left to right, before and after zMAX®). And, as of late August, 94 of OmniTRAX’s 102-unit fleet have been treated with zMAX®.
It wasn’t an easy sell for Allen, especially to skeptical senior-level railroaders. But eventually, seeing was believing. “I had the opportunity to show Senior Vice President of Operations Gord Anutooshkin a locomotive treated with zMAX® at our Chicago Rail Link location,” Allen says. “We looked at the upper deck and air box of a GP38-2, and Gord was impressed with the cleanliness and overall coating that we observed on this unit. Composite Mechanic Dennis Sabo, a 25-year veteran, talked about how he thought we were introducing another ‘snake oil,’ and that he was impressed to see a product that actually works in cleaning up the engine and exhaust. Gord agreed with my plan to keep utilizing zMAX® on our fleet.”
Chicago Rail Link began using zMAX® in January 2017. 20W40 oil sample analysis reports from Tribologik Corp. conducted in November 2016 and May 2018 revealed the following before/after zMAX® results: Soot, a measure of combustion efficiency, dropped dramatically from 1.08% to 0.75%. Copper levels dropped nearly 50% from 35 PPM (parts per million) to 19 PPM, as did aluminum, from 4 PPM to 2 PPM. Kinematic viscosity at 100 degrees C stayed in check, dropping slightly from 15.78 cSt (centistokes) to a stable 13.90 cSt, well within tolerance. “Oil stays cleaner longer,” Allen notes. “Oil consumption is reduced. Engines are cleaner, and zMAX® provides extra protection during start-up. Engine components are better protected, and seals are more pliable and effective.”
OmniTRAX also evaluated upper and lower rod bearing wear during a repair procedure. The bearings, after seven years of run time, three of them with zMAX®-treated oil, at first glance showed normal rotational wear. Upon further inspection (below), “there was no damage or flaking of the soft overlay lead on the bearings, which looked almost new except for initial rotation break-in marks. The upper bearings (left, center photo is a lower rod bearing) had very limited wear. Usually, the upper blade rod (right) has polished the surface by this time, but with zMAX® use, all test locomotive engines are showing very limited wear. The bearings could be used again if need be.”