Maritime Knowledge Base
Browse questions and answers across marine machinery, merchant navy careers, shipboard operations and maritime glossary terms.
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Marine Machinery
Troubleshooting guides for pumps, boilers, purifiers, compressors and auxiliary systems.
Merchant Navy Careers
Questions about joining the merchant navy, exams, cadetships, ranks and sea-time.
Maritime Glossary
Plain-English definitions of shipping, engine-room, navigation and regulatory terms.
Shipboard Operations
Practical Q&A for watchkeeping, safety, maintenance routines and onboard documentation.
Results for "Fuel oil"
How does a ship's fuel oil system store, treat and deliver fuel to the engine?
The fuel oil system takes bunkers from the storage tanks, settles and purifies them, heats heavy fuel to the right viscosity, and delivers clean fuel under pressure to the engine.
Marine MachineryWhy does the auxiliary boiler flame keep failing or the burner keep tripping?
Repeated boiler flame failure trips the burner on the flame monitor — the causes run through the fuel, the ignition, the air and the flame-detection system.
Marine MachineryHow does a marine boiler work?
A marine boiler generates steam by transferring heat to water — this covers the working principle and the difference between oil-fired and exhaust-gas boilers.
Marine MachineryHow does a marine centrifugal oil purifier work?
A marine purifier cleans fuel and lubricating oil by spinning it at high speed so that water and solids separate out — here is the working principle.
Marine MachineryWhy is my fuel or oil purifier not separating properly?
The usual causes of poor purifier separation — feed rate, temperature, gravity disc and water seal, sludge and bowl condition — and how to work through them one at a time.
Marine MachineryWhy won't the main engine start on air?
A main engine that turns on air but will not fire, or will not turn at all, points to a short list of common causes across the starting-air, fuel and control systems.
Marine MachineryHow does a marine diesel engine work?
A marine diesel engine converts the chemical energy of fuel into rotary motion through compression ignition — here is the working principle and the two-stroke and four-stroke cycles.
Marine MachineryWhat is the difference between a two-stroke and a four-stroke marine engine?
Two-stroke and four-stroke marine engines differ in how many strokes complete a cycle, their speed and size, and the roles they play aboard ship.
Marine MachineryWhat is the difference between a purifier and a clarifier?
A purifier separates both water and solids from oil, while a clarifier removes only fine solids from oil that contains little or no water — often the two run in series.
Marine MachineryHow does a marine incinerator work and what can it burn?
A marine incinerator burns the ship's waste oils, sludge and solid garbage in a combustion chamber, subject to MARPOL rules on what may be incinerated and where.
Shipboard OperationsWhat are the classes of fire and which extinguishers are used on ships?
Fires are grouped into classes by what is burning, and each class needs the right extinguishing agent — using the wrong one can be ineffective or dangerous.
Marine MachineryHow does a marine heat exchanger work?
A heat exchanger transfers heat from one fluid to another through a dividing wall without letting them mix — used all over a ship to cool engines, oil and air.
Marine MachineryWhat causes a fluctuating water level in a marine boiler?
Why a boiler gauge glass swings — priming, foaming, load swings, feed control and level-sensor faults — and the safety response when the true level is in doubt.
Marine MachineryWhy is the main engine lubricating oil pressure low?
Low lubricating oil pressure is a serious alarm that threatens the bearings — the cause is usually in the pump, the filters, the oil itself, or a leak.
Shipboard OperationsWhat should be checked during engine-room watchkeeping rounds?
How to make an engine-room round count — comparing live readings against normal ranges and catching trends before they become failures.
Maritime GlossaryWhat is deadweight tonnage (DWT)?
Deadweight tonnage defined — the total weight a ship can carry — and how it differs from displacement and gross tonnage.
Marine MachineryWhat causes a scavenge fire in a two-stroke marine engine?
A scavenge fire is the ignition of accumulated oil and carbon in the scavenge spaces of a two-stroke engine — here is why it happens and how to respond.
Shipboard OperationsWhat is an inert gas system on a tanker and why is it needed?
An inert gas system fills a tanker's cargo tanks with oxygen-poor gas so the atmosphere cannot support combustion, preventing explosions in and around the cargo.
Marine MachineryWhat causes a marine engine turbocharger to surge?
Turbocharger surging is a violent, audible instability of the airflow through the compressor — it signals a mismatch between the turbocharger and the engine's demand.
Marine MachineryHow do you recover from a blackout (total loss of electrical power)?
A blackout is the total loss of electrical power on a ship — recovery depends on the emergency generator, restarting the main plant and restoring services in the right order.
Shipboard OperationsWhat is a hot work permit and when is it needed?
A hot work permit controls any work involving heat, flame or sparks outside a designated safe area, confirming the space is gas-free and fire precautions are in place.
Marine MachineryHow does a marine engine turbocharger work?
A turbocharger uses the energy of the engine's exhaust gas to drive a compressor that forces more air into the cylinders, greatly increasing power and efficiency.
Marine MachineryHow does a marine fresh water generator (evaporator) work?
A fresh water generator makes drinking and technical water from seawater by boiling it under vacuum using waste heat from the engine, then condensing the vapour.
Marine MachineryWhat is cylinder lubrication in a two-stroke marine engine?
Cylinder lubrication is the separate oil supply fed onto the liner of large two-stroke engines to lubricate, neutralise fuel acids and keep the surfaces clean.
Marine MachineryWhat is jacket cooling water in a marine engine?
Jacket cooling water is the treated fresh water circulated through the passages, or jackets, around an engine's cylinders to carry away combustion heat and keep it at its correct working temperature.
Shipboard OperationsHow does a fixed CO2 flooding fire-extinguishing system work?
A fixed CO2 system extinguishes a fire in a protected space such as the engine room by flooding it with carbon dioxide, which displaces the oxygen the fire needs — after everyone is evacuated.
Marine MachineryWhat is a governor on a marine engine and what does it do?
A governor automatically controls an engine's speed by adjusting the fuel supply to match the load, keeping the engine at the required revolutions or a generator at constant frequency.
Marine MachineryWhat is scavenging in a two-stroke marine engine?
Scavenging is the process of pushing the burnt exhaust gases out of a two-stroke engine cylinder and replacing them with fresh air, ready for the next combustion cycle.
