Question 452Motor Plants - Assistant Engineer

The correct answer is A) worn main bearing journals. Crank web deflection readings can indicate the condition of the main bearing journals. If the main bearing journals are worn, the crank webs will show increased deflection or movement when the engine is running. This is because the worn bearing journals allow more movement or "play" in the crankshaft, which results in measurable deflection of the crank webs. The other options (B, C, and D) do not directly relate to the information provided by crank web deflection readings.