🔍 Key Concepts

• Trace the piping connected to the device labeled 1 to see which system it belongs to (lube oil, jacket water, starting air, or crankcase ventilation). • Consider where combustible gases might be produced in a diesel engine and how they are safely handled. • Think about the difference between a pressure‑relief device and a venting/filtration device and where each would be located.

💭 Think About

• From the illustration, where does the line from device 1 lead, and what major component is it associated with on the right side of the drawing? • Which of the listed functions would logically require a connection to the crankcase area, and which would more likely be connected to jacket water or combustion air systems? • If the jacket water system needed a relief or chemical injection point, would it most likely be shown near the cooler (24) or somewhere else—does that match the location of 1?

✅ Before You Answer

• Verify which system boundary device 1 is drawn in: is it part of the cooling water, starting air, or crankcase/lube oil arrangement? • Check whether device 1 is connected to an enclosed space that can accumulate vapors or gases, rather than to a water-filled component. • Confirm that none of the other labeled items near the jacket water cooler (such as 25–27) already perform the pressure relief or venting functions for that cooler.