Final answer:
In an OHV pushrod engine, the cam and crank should be rotated so the timing chain and sprockets can be installed with the marks on both sprockets pointing straight up. This ensures correct timing and engine performance.
Step-by-step explanation:
In the assembly of an OHV pushrod engine, precision in timing chain and sprocket installation is paramount for optimal engine performance. The correct procedure involves rotating both the cam and crank so that the timing chain and sprockets can be affixed with their marks precisely oriented straight up. This meticulous alignment signifies the synchronization of the camshaft and crankshaft, a critical factor in ensuring the engine's proper functionality.
When the marks on the sprockets align vertically, it serves as a visual confirmation that the camshaft and crankshaft are in sync, preventing potential timing discrepancies. This meticulous alignment guarantees the accurate opening and closing of valves in relation to the piston position, fostering efficient combustion and overall engine operation.
In essence, Tech A's assertion regarding the necessity of having the sprocket marks pointing straight up during the timing chain and sprocket installation is accurate, as it establishes the foundation for the engine's precise timing and optimal functionality.