From past experience, Gobel estimates that a Caterpillar 3508 engine will generate approximately 25 to 40 ppm of iron particles at a 250--hour change when using conventional oil. "Those numbers are not out of the ordinary," says Gobel.
But with the combination of synthetic oil and the Spinner II centrifuge, the particle count is much less than this, even at 1,000 hours. "Ten or 12, sometimes 15 ppm is the most we will see," says Gobel. "We take the wear metals out and therefore have less abrasion from the oil as it travels back through the engine again."
Soot generation really varies by the application. The dozers, by their nature, tend to generate more soot. "But with the Spinner II, we have been able to keep our soot levels at about a third of what other people were able to do," says Gobel. "We feel like that considerably increases the probabilities of our engines living longer."
Marco Supply now has a proven maintenance schedule. "We change the full flow filters at 500 hours and we also check our Spinners at that time," says Gobel. "At 250 hours, we sample our oil. We also sample it at 500 hours and 750 hours so we know where we stand."
The results indicate that oil drains could be extended further, but Gobel says he is comfortable with the 1,000--hour intervals. "On a 3500 Series Caterpillar engine, the payback would be in the first 1,000 hours," claims Gobel. This includes the increased availability and reduced oil and service time costs.
Cost of the Spinner II varies by size. For the standard 2--gpm unit used on engines in the 250--hp range, Weaver estimates the installed cost to be in the area of $650 to $750.
System cleans and replenishes
PuraDYN Filter Technologies Inc. offers a complete bypass system that filters the oil and replenishes the additives. Oil enters this system and passes through the replaceable filter element, where total base number (TBN) additives are replenished. Long--strand cotton fibers are compressed to resist channeling and remove contaminants down to less than 1 micron.
The filtered oil then enters a heat evaporation chamber where fuel and water vapors are evaporated and vented, removing components that contribute to generation of acid in the oil.
"We normally run about 6 gal. per hour," says Kevin Kroger, president, PuraDYN Filter Technologies Inc. "There is enough going through our bypass filter that it literally keeps the full--flow filter clean."
The size of the particles that are left typically will not harm the engine. "Because of the fine filtration, we are able to filter below the clearance gap on most engines," says Kroger. "Let's say the clearance gap is about 2 microns, which it is on most engines. We are filtering below 1 micron. Therefore, any solid contaminants passing through the system should be able to pass through the clearance tolerances on the engine. You reduce the amount of wear on these surfaces."
This system successfully removes soot particles from the oil before they can cause excessive wear. "When soot itself actually enters the oil, it is submicron," says Kroger. "But as time progresses, it coagulates with others. Then they start growing." Since soot is basically made up of carbon, a very hard substance, these particles can cause a lot of damage.
A full--flow filter will catch these soot particles once they grow to 5 to 10 microns. "Remember what I said about the clearance of our engine at 2 microns? Now I have a 5--micron particle going through there," says Kroger. "Our system is able to remove that particle before it gets to that size."
Richard Ford, co--founder, PuraDYN Filter Technologies Inc., reports that this system has been installed on many Caterpillar ACERT engines with success. "We are keeping the soot under 1%. They were changing oil before at 350 hours and now we are taking them out to 1,050," he states. "They are just changing both the synthetic full--flow filter and our filter."
For engines in the 250-- to 500--hp size range, Kroger estimates the installed cost to be between $500 and $600. "It would run you somewhere in the neighborhood of about $20 to $25 for the replacement filter," he says. "In the off--highway side of the business, payback is real quick. We have seen return as short as six weeks and as long as a couple of months."