What tool is generally used to measure the crankshaft rotation in degrees?

The timing disk is a tool specifically designed to measure crankshaft rotation in degrees. It is typically a circular disk with markings corresponding to the degrees of rotation. When attached to the crankshaft, it allows for precise measurement of the crankshaft's position as it rotates. This is crucial for setting timing for ignition and valve operations in reciprocating engines, as accurate timing is essential for optimal performance and efficiency.

In contrast, a dial indicator is utilized for measuring small distances or alignments but doesn't provide the necessary rotational measurements in degrees. A prop protractor, while useful in measuring angles, is not specifically designed for measuring crankshaft rotation. A torque wrench is focused on applying a specific torque to a fastener rather than measuring rotational angles. Therefore, the timing disk is the most appropriate tool for accurately measuring crankshaft rotation in degrees.