Auxiliary Officer and Electrical Division Section 1 Common Core Practice Test

The main idea is that line shaft bearings keep the shaft in place and let it rotate smoothly by providing radial support. As power is transmitted along a line with belts and pulleys, the shaft experiences sideways forces that can cause bending or deflection. The bearings hold the shaft steady, maintain alignment of pulleys and gears, and reduce bending so the system runs efficiently with less wear. Lubrication comes from a separate lubrication system, not from the bearing itself, and while good support can help keep vibration down, the primary function is to resist radial loads and keep the shaft aligned. Sealing the crankcase is an engine-specific role and not part of what line shaft bearings do.