🔍 Key Concepts

• Lube oil system pressure control in diesel engines during cold starts • The function of a relief valve in a pressurized system • Difference between pump characteristics (capacity, speed, outlet pressure) and pressure limiting devices

💭 Think About

• When oil is cold and thick, what would happen to system pressure if there was no device to limit it? • Which of the listed components is specifically designed to open or bypass flow once a set pressure is reached? • Do pump capacity or speed actively limit pressure, or do they simply influence how much pressure could be produced if not otherwise controlled?

✅ Before You Answer

• Identify which option is a pressure-limiting safety device, not just a pump characteristic • Confirm which component reacts automatically when set pressure is exceeded • Eliminate any options that only describe how much oil the pump can move, rather than how pressure is kept from going too high