General Engineering Flashcards

What is the primary purpose of a diesel engine's intercooler?

Answer: To cool compressed intake air before it enters the cylinder

An intercooler cools compressed air from the turbocharger before it enters the cylinder, increasing air density and allowing more fuel to burn efficiently.

On a marine vessel, what type of pump is most commonly used for bilge pumping operations?

Answer: Centrifugal pump

Centrifugal pumps are most commonly used for bilge service due to their ability to handle large volumes of water and their self-priming capability when fitted with a foot valve.

What is the function of a sea chest in a ship's cooling water system?

Answer: To provide a protected intake for seawater used in cooling systems

A sea chest is a hull fitting with a strainer that provides a protected seawater intake point for the ship's cooling and other seawater systems.

When checking a diesel engine's injection timing, which instrument is typically used?

Answer: Timing light or dial gauge on the flywheel

Injection timing on a diesel engine is checked using a timing light or a dial gauge referenced to degree markings on the flywheel.

What does the term 'MARPOL' refer to in marine engineering?

Answer: Marine Pollution Prevention Regulations

MARPOL stands for the International Convention for the Prevention of Pollution from Ships, governing discharge of oil, sewage, garbage, and other pollutants.

In a ship's electrical system, what is the purpose of a bus bar?

Answer: To serve as a common conductor connecting multiple circuits

A bus bar is a metallic conductor that acts as a common connection point distributing electrical power from generators to various shipboard circuits.

What causes diesel engine 'knock' during operation?

Answer: Ignition delay causing a large amount of fuel to ignite simultaneously

Diesel knock is caused by ignition delay — fuel accumulates in the cylinder before combustion starts, then all ignites at once, causing a rapid pressure rise and audible knock.