🔍 Key Concepts

• heat exchangers and how jacket water and sea water flow are separated by tube walls • why pressure differences between two fluids matter for leak direction • practical temperature ranges of jacket water and sea water in normal engine operation

💭 Think About

• Which fluid do you most want to protect from contamination if a leak develops: the internal fresh water jacket system or the external sea water system? • If there is a pinhole leak in the cooler tubes, should the higher pressure be on the side you want to keep clean or on the side that is more corrosive/dirty? • Do the specific temperature limits mentioned in the choices (40°F and 60°F) sound like fixed rules for all engines and all ocean conditions, or are pressure relationships more likely to be a standard design principle?

✅ Before You Answer

• Verify which side (jacket water or sea water) is fresh/treated and which is salt/corrosive. • Check which fluid you would rather be pushed into the other in case of a leak – that tells you which one should have the higher pressure. • Consider whether strict temperature numbers (40°F, 60°F) are realistic and universal, or whether operating temperatures normally vary with engine load and sea conditions.