🔍 Key Concepts

• Purpose of a water-lubricated stern tube or stuffing box • Why some controlled leakage is necessary for cooling and lubrication • Consequences of too little vs too much leakoff at the packing gland

💭 Think About

• Think about what the packing is supposed to do: completely stop water, or allow a small, controlled amount for lubrication and cooling? • What might happen to the shaft, packing, and bearing if the packing gland is tightened so much that no water can pass? • What might happen in the engine room if the packing gland is left so loose that water flows freely?

✅ Before You Answer

• Cooling and lubrication needs of a water-lubricated stern tube bearing • Safe leakoff rate that prevents overheating while avoiding excessive flooding • Whether the description in each choice would likely cause overheating or excessive leakage while underway