When replacing the timing belt on a dual overhead engine, the technician should.

• A. Mark the timing marks on the gears
• B. Lock the cams in place
• C. Install the belt loosely
• D. Remove the crankshaft pulley

Answer: (B)

On a dual overhead cam engine, the timing belt links the crankshaft to two camshafts that can move independently. When you remove and reinstall the belt, the camshafts could shift slightly, throwing the valve timing out of sync. Locking the camshafts in place holds them exactly where they need to be while you install the belt and set tension, ensuring the timing remains correct and the engine runs properly after service. Marking timing marks can help verify alignment, but without locking, movement during belt removal could still spoil the timing. Installing the belt loosely would fail to establish proper tension and timing, and removing the crankshaft pulley isn’t required for this procedure and just adds unnecessary steps.