Question 527Steam Plants - Assistant Engineer

The correct answer is C) observing the overflow sight glass. In a gravity-type lube oil system, the gravity tanks are the source of lubricating oil for the machinery. After starting the main lube oil pump, the proper way to verify that the gravity tanks are full is to observe the overflow sight glass. This allows you to directly confirm that the tanks are at the proper level and that the oil is flowing as expected. Sounding the lube oil sump (A) or the gravity tanks (B) would not directly confirm that the tanks are full. Observing the flow from the bearings (D) would not conclusively show that the gravity tanks are full, as the oil could be circulating without the tanks being at the proper level.