Independent · Australian · No brand ties

Your engine is a system. Read it like one.

63 pages on marine diesels, saildrives, gearboxes, propellers and gensets — written for Australian owners who want to know what failed, what it costs, and when to stop and call someone.

Start the guide Something's wrong now

Guide pages: 63
Answers: 13
Brands: 10
Regions: 9

Panel check

Tap a reading

Oil pressure Coolant temp Charge

Three readings tell you most of what an engine is doing. Learn what each one means before it moves — not after.

Engine trouble nowPick the closest symptom

Won't crank Cranks, won't start Starts then stops Losing power Overheating Black smoke Alarm sounding Vibration

What this is

More than an engine block. A connected system.

A marine diesel sits at the centre of the fuel tank, filters, cooling-water intake, heat exchanger, exhaust, batteries, controls, gearbox or saildrive, propeller and hull. A fault in any one of them can make a healthy engine look broken.

We sell nothing, take no referral fees and endorse no brand. That is the whole editorial position, and it is why the advice here occasionally ends with stop, this is a technician's job.

The guide

Ten sections, 63 pages

02 pagesStart hereWhat this guide covers and the order that makes it easiest to learn.14 pagesEngines & systemsParts, the four-stroke cycle, fuel, air, cooling, oil, exhaust, electrics, instruments and sizing.08 pagesPropulsion & drivesShaft drives, saildrives, sterndrives, pods and waterjets, gearboxes and propellers.11 pagesMaintenance & servicePre-start checks, service schedules, oil, filters, impellers, anodes, alignment and lay-up.12 pagesTroubleshootingSymptom-first diagnosis: no crank, no start, overheating, smoke, alarms, vibration and emergencies.03 pagesPerformance & fuelOperating rpm, fuel consumption, cruising range and efficiency.04 pagesRepower & buyingReplacing an engine, installation and commissioning, used-engine surveys and ownership costs.04 pagesGeneratorsMarine genset selection, sizing, installation and fault finding.03 pagesAustralian rulesStandards, compliance, refuelling and pollution rules, and when the work belongs to a professional.02 pagesReferenceBrands overview, service records, FAQ, glossary and printable checklists.

Navigate by intent

Start with your goal

Understand itHow a marine diesel works Compare layoutsMarine propulsion types Yacht saildrivesSaildrive systems Build a routineService schedule Diagnose a failureTroubleshooting Calculate rangeFuel consumption and range Replace an engineRepowering a boat Add a gensetMarine diesel generators Know the rulesAustralian standards

How to be a safe owner

The owner's three levels of work

01ObserveKnow the normal sound, temperature, exhaust-water flow, charging voltage and vibration. Most serious faults announce themselves through a change.

02MaintainFollow the model-specific schedule for oil, filters, coolant, belts, impellers, anodes and drive lubricant. Record hours, dates and findings.

03DiagnoseProve whether the problem is fuel, air, cooling, electrical, exhaust or propulsion before buying parts. Disciplined diagnosis is faster and cheaper.

The safest owner is not the one who can rebuild an injection pump. It is the one who notices a new leak, knows which seacock feeds the engine, reacts correctly to an alarm and can give a technician precise information.

Safety notice

This guide explains systems, checks and diagnostic logic. It is not a substitute for the manual for your exact engine, gearbox, saildrive or generator. Diesel fuel, hot coolant, rotating machinery, high-current DC, 230 V AC, pressurised common-rail injection, exhaust gases and lifting can cause serious injury or death. Stop when a task needs licensed electrical work, specialist test equipment, fuel-injection work, lifting, machining or judgement beyond your training.

Australian scope

Recreational boating rules are administered mainly by state and territory authorities. Domestic commercial vessels generally fall under the national system administered by AMSA. Standards and rules change. Confirm the requirements that apply to your vessel, location and intended operation before altering an installation.