Technicians have a new tool to find costly air- and exhaust-system leaks in Redline Detection’s HD PowerSmoke tester, which injects mineral-oil vapor into the air stream of a running engine. The device works with the engine off and vapor replaces the process of introducing dyes, which is less certain way of finding leaks, the company says.

A modern heavy duty truck diesel runs on fuel and air that travels through a series of pipes, fittings and mechanisms, then through the exhaust aftreatment system with its oxydation catalyst, urea injection chamber and diesel particulate filter, Redline explains. All components should stay tight or efficiency drops and contaminants can enter and cause expensive damage. But leaks can develop over time, distance and road shocks, and they’re sometimes hard to find.

With the engine shut down, a technician connects the HD PowerSmoke device at the air inlet, then injects mineral oil vapor, pumping it through the turbocharger, charge air cooler, intake manifold, cylinders, crankcase and through the exhaust system. Patent-pending inflatable plugs at the intake box and tail pipe keep the vapor confined.

White vapor puffs out wherever there’s a leak and is plainly visible in the yellowish beam of a strong halogen light wielded by the tech, Redline says. The tech alters air pressure to expand or reduce the amount of smoke that escapes at any leak. He can then make repairs.

The HD PowerSmoke is similar to Redline Detection’s earlier SmokePro machines, but is specifically designed for heavy duty truck and off-road engines. Valley Power Systems, a WheelTime network member with 10 locations on the West Coast, is using the machines. And one major truck manufacturer’s dealers are equipping their shops with the product, Redline says. A demonstration video is here