Which of these conditions does NOT indicate that a V-belt drive sheave needs to be replaced?

The condition that suggests the V-belt drive sheave does not need replacement is when the top surface of the belt is worn. While wear on the belt itself is an important indicator of maintenance needs, it typically signifies that the belt may need to be replaced rather than the sheave.

The belt can wear out due to factors such as misalignment, tension issues, or normal operational wear and tear. This is a common maintenance item that can be changed without necessarily needing to replace the sheave. If the sheave itself is in good condition regarding its groove, structure, and alignment, it can continue working effectively even if the belt shows signs of wear.

On the other hand, visible cracks on the sheave, excessive wear or scoring on the groove surface, and being out of round are all significant indicators of sheave damage. These conditions can lead to poor belt performance, increased friction, and ultimately mechanical failure if not addressed. Thus, identifying a worn belt does not immediately indicate the need for a sheave replacement, making this condition the correct choice for indicating that the sheave itself does not require replacement.