Question 415General Subjects - Assistant Engineer

The correct answer is C) The pump delivers full capacity when started, but gradually slackens off to an abnormally low flow. Excessive air leakage into the suction side of a centrifugal pump would cause the pump to lose its prime, resulting in a gradual reduction in flow over time. This is because the entrained air reduces the pump's ability to create suction and draw liquid into the impeller, causing the pump's performance to deteriorate. The other answer choices do not directly relate to the effects of excessive air leakage, as they describe issues such as motor overload, packing gland overheating, and suction pounding, which have different underlying causes.