During belt-drive alignment, which checks should be performed?

• A. Only pulley diameter and belt width
• B. Belt tension and pulley runout
• C. Parallel and angular shaft alignment, belt tension, pulley runout, and belt tracking
• D. Belt color and material

Answer: (C)

During belt-drive alignment, you want the belt system to behave as if all moving parts are sharing the same path and load. This means ensuring the shafts are lined up in both position and angle, the belt has the right tension, the pulleys aren’t wobbling (no runout), and the belt stays centered on the pulleys (proper tracking). When shafts are parallel and properly angular, the pulleys sit on the same axis and don’t twist relative to each other, which prevents edge wear and uneven belt contact. Correct belt tension keeps the belt from slipping or stinging the bearings from excessive load, and it also helps maintain stable tracking. Checking pulley runout catches any wobble in the pulleys that would force the belt to ride or migrate toward one edge, causing uneven wear and noise. Verifying belt tracking confirms the belt remains centered during operation, preventing it from walking off or rubbing against the pulley flanges.

The other options miss essential parts of a proper belt-drive alignment. Focusing only on pulley diameter and belt width ignores alignment, tension, tracking, and runout, which are all critical for reliable operation. Emphasizing belt tension and pulley runout alone leaves out alignment and tracking, and belt color or material has no bearing on the mechanical alignment or performance.