"I can’t imagine any fleet or repair facility not adopting this. We have no more unsolvable upstream leak issues. This technology is going to change the way we test, diagnose and repair heavy duty vehicles.”
Chris Michael, Valley Power Systems, in Diesel Progress
ACCELERATED LEAK DIAGNOSTICS
BY CHAD ELMORE
Leaks in a heavy-duty truck’s exhaust system can be a health hazard to operators and errant holes in an air intake system can cause big problems with aftertreatment devices. Tracking down the source of a leak can be a time-consuming and thankless task. Redline Detection LLC has introduced patent-pending technology intended to help heavy-duty equipment technicians and engineers in that search. The company said the new tool can turn a troubleshooting task that can normally take hours into a solitary 10 minute procedure.
Chris Micheal, WheelTime truck service network champion for Valley Power Systems, has been field-testing the new technology. “We are using this equipment every day and are seeing substantial savings in time, parts, costs and overall efficiency,” he said. “I can’t imagine any fleet or repair facility not adopting this. We have no more unsolvable upstream leak issues. This technology is going to change the way we test, diagnose and repair heavy duty vehicles.”
Based in City of Industry, Calif., Valley Power Systems is a distributor for a wide range of engines. It is a founding member of WheelTime, which has more than 200 locations in the U.S. and Canada.
The new HD PowerSmoke leak detection system from Redline Detection is designed for heavy-duty trucks, buses, construction equipment and agricultural applications with engines up to 15 L.
The technology was established in passenger and performance cars before a request from a heavy-duty truck manufacturer led to the development of a heavy-duty version of the system. Since then, many on-road and offhighway equipment manufacturers have worked with the company to develop a device tailored to their machines, Redline said. According to the company, those firms have listed the tool as mandatory or approved equipment at their dealer service centers.
Over-the-road truck drivers don’t usually pull in for service because they have detected an air leak in their truck’s intake system. The problem usually manifests itself as a performance issue.
“The most common complaint is too many DPF (diesel particulate filter) regeneration events,” said Bill Woods, senior sales executive for Redline’s heavy-duty business. “It doesn’t matter if it’s an F-350 or a semi truck. If the vehicle is having more regens than normal, there’s a leak on the intake side of the turbocharger. We usually find that the clamp on the turbo is a problem point as well as couplers and cracked charge-air coolers. The largest number of leaks I’ve found in trucks are generated by workmanship, not component failure.
“When technicians check a system, it’s common practice to remove the charge-air cooler and isolate it during a test, but doing that removes the leaky connector. They’ll test the part and when it passes, they put the leak right back on the truck. Technicians will spend hours tearing apart the truck to fix a leak caused by installing a clamp improperly.”
HD PowerSmoke uses shop compressed air to maintain a pressure of 2 to 20 psi throughout the intake and exhaust system with the vehicle’s engine switched off. Expanding adaptors seal off entrances and exits while a dense, highly visible vapor flows through the truck’s hoses, tubes and related components. The steam is created by vaporizing mineral oil and has no contaminants that could harm or coat sensors, Redline said. It flows through the pressurized system and out any tiny holes that are present so technicians can see the source of the trouble.
“Another common problem is that the truck is using a lot of DEF (diesel exhaust fluid),” Woods said. “With HD PowerSmoke hooked up to the truck, I’ll find a leak within 10 in. of the dosing valves. The hole lets more oxygen into the system, which causes DEF to crystalize before it does its job. The truck will start burning through a bunch of DEF but will still be running fine.”
Leaks can also cause a diesel engine’s air management system to overcompensate with the fuel rate. “The truck could be running 10 to 20% fat — not enough to smoke but enough to cause a DPF clog,” Woods said. “It might cause a 0.5 mpg drop in mileage, which won’t throw a fault code and isn’t enough for the driver to notice. It’s the worst-case scenario for shops: there’s no code, but the truck is having a problem and they can’t find the cause.”
HD PowerSmoke uses variable pressure and flow rates to replicate boost load and allow the technician to adjust flow as needed to find tiny faults, Redline said. Different leaks show up at different pressures, so it’s critical that technicians can dial the pressure up or down to replicate engine boost, the company said.
Engineered and built by Redline at its headquarters in Southern California, the kit includes two PowerSmoke adaptors, a 60 in. SmokeMeister wand, smoke nozzle, cooling system adaptor, pressure oxygen and temperature port adaptors, vapor-producing fluid, spare quick connect couplers and a halogen inspection light.
“Verifying that the part is bad is often more important than the diagnostics of it,” Woods said. “You want to verify a part is actually bad before you replace it and the only way I know to verify that those tubes are OK is to pressurize and test the system with HD PowerSmoke.
“’Parts darts’ is not an effective repair procedure. It doesn’t matter what system it is. You need to know air is getting through it cleanly and efficiently to be sure it’s doing a proper job. For fleets, HD PowerSmoke technology is ending the pain of unsolvable upstream leak issues and the health hazard of exhaust leaks in the cab.”