🔍 Key Concepts

• Hydraulic motor construction: especially the rotating shaft and how it exits the housing • Shaft seals and packing: what their job is in keeping oil inside around moving parts • Difference between internal system problems (like suction or RPM) and local sealing problems (like leaks at one spot)

💭 Think About

• Ask yourself: which option directly affects the tightness of the area where the shaft passes through the housing? • Consider: if the pump lost suction or the RPM changed, would that cause a visible local leak at the shaft or more of a performance issue (slow/weak system)? • Think about what component is installed specifically to prevent fluid from escaping along a rotating shaft.

✅ Before You Answer

• Identify which choice refers to a component at the shaft/housing interface (not a system-wide condition). • Eliminate any options that mainly affect flow, pressure, or speed but not sealing at the shaft. • Verify which condition would most logically cause external leakage at a single point rather than overall hydraulic failure.