Oil supply pressure to the main lube oil header of a gravity feed lube oil system is __________.

Correct Answer: Option C — the result of the height of the gravity tank above the manifold

In a gravity lube oil system, the pressure at the main header is determined strictly by the vertical height between the gravity tank and the distribution manifold. This static head provides a constant, reliable pressure independent of pump fluctuations, ensuring uninterrupted bearing protection during maneuvering.