One of the more critical elements now developing with emissions control systems is the maintenance of DPFs to prolong life and ensure performance — and that is putting greater emphasis on cleaning and testing.
“We believe testing the DPF once it's been cleaned is really the most critical part of the process,” says Jeff Sass, general marketing manager for Paccar Parts. “We spent a lot of time researching DPF cleaning machines, and we found the testing component to be absolutely vital to verifying it's ready to be placed back into service.
“We conducted extensive tests on three of the leading DPF cleaning machines, including [one from] FSX,” Sass says. “We found the FSX machine got filters 9% cleaner than the next best…machine.”
He notes that over time and multiple cleanings, an additional 9% worth of soot and ash accumulates and could lead to increased cost, downtime and quite possibly engine failure for trucks equipped with DPFs. “In our performance tests, we also found that after the first pass, the FSX machine cleaned a filter to acceptable air flow 23% more often than the next best performing machine,” he says.
A standard DPF cleaning using the FSX machine takes 20 to 60 minutes, adds Sass, with a thermal cleaning using the FSX machine's TrapBurner running about nine hours.
The FSX testing feature — called the TrapTester 7 — is just as important. This is an air flow test bench that checks a filter before and after it is cleaned to determine the extent of ash buildup, Sass says.
“Without the testing capability, it's impossible for technicians to know how clean the filter is after a DPF cleaning,” says Sass. “The air flow test allows them to determine if the filter is clean enough to re-install on the vehicle, and clean enough so undue backpressure won't build up in the device, which leads to more stress on the DPF, potentially damaging it and lowering its life expectancy.”
David McKenna, director of powertrain sales & marketing for Mack Trucks, notes that his company prefers to use the term “conditioning” when it comes to DPF maintenance because there is more to this activity than a visit to “a very high performance vacuum cleaner.”
The cores are inspected, X-rayed, baked and then cleaned. This process affords a much more consistent level of ash removal that is the key to a longer second life for the DPF,” he says. “A lesser cleaning results in a much shorter second life as there is less surface area available to efficiently trap soot.”