🔍 Key Concepts

• Cylinder liner lower seals and what they are intended to keep separated • The difference between crankcase, cooling water jacket, lube oil system, and scavenge air space in a medium-speed V-type diesel • How leakage past the liner seals would be detected or where that leakage would drain/collect

💭 Think About

• Look at the illustration and trace what fluid or space is located immediately outside the lower part of the liner – does it connect to the crankcase, the cooling jacket, or an air box? • Ask yourself: if the lower seals failed, where would the cooling water (or other fluid) go, and how would that show up during inspection? • Consider which system would be most dangerous to mix with lube oil in the crankcase and how designers usually arrange the space under the liner to help detect that problem early.

✅ Before You Answer

• Identify in the drawing where the cooling water jacket ends and what color/area represents it. • Confirm whether the area just below the liner and above the crankcase is open to the crankcase atmosphere or to a pressurized air box. • Verify that lube oil pressure is normally confined to drilled passages and bearings, not to large open spaces around the liner.