Bendix Commercial Vehicle Systems, LLC, has released its newest Bendix Tech Tips series, which this month provides maintenance tips for air systems used by automated manual transmissions (AMT) and advanced safety technologies.
Bendix says Many AMTs on the market utilize a mechatronic shifter, which combines the intelligence of electronic controls with the reliability and high power density of pneumatics. The compressed air to control these AMTs is supplied by the engine’s existing air compressor. Furthermore, most automated air controls on trucks utilize multiple electronically operated solenoids, which require both cleaner and dryer air than traditional manual brake valves, and are sensitive to both small particulate and oil contamination.
Poor Air Quality: Know the Signs
Early indicators of poor air quality can occur downstream of the compressor and air dryer, in the systems that rely on effective functioning of components such as solenoid valves for pneumatic automation and emissions controls.
“These components have very tight tolerances, and if there’s too much of that ‘toxic brew’ of contaminants, engine oil, and water, it leads to mechanical malfunctions due to fouling within valves, for example,” says Richard Nagel, Bendix director of marketing and customer solutions, Air Charging. “That’s actually how many customers first realize there’s a problem with the air system: Drivers will report noticeable performance changes, like malfunctioning brake valves or an AMT not engaging or operating as smoothly as expected.”
Bendix says other signs include an excess of oil mixed with water found when regularly draining the air system tanks, and the need to replace air dryer cartridges more frequently than expected. What steps can a tech take to address an air contamination issue? From a practical standpoint, the two key points within the air system for controlling air quality are the compressor and the air dryer.
