Sailors love wind; Motorboaters love horsepower but at some point, your trip will probably depend entirely on a small, hardworking diesel engine.

It might be you’re trying to punch the tide into a harbour, dodge a squall, or just get safely alongside when the wind dies at the worst possible moment; you reach for the ignition key, but the engine doesn’t start — or stops unexpectedly — you need to fix things fast…. Or better still have a cared for engine that won’t let you down.

That’s exactly why the RYA Diesel Engine Course has become one of the most valuable one-day courses a skipper or crew can take. It isn’t about turning boaters into mechanics. It’s about giving you the knowledge to prevent most common problems — and the calm, practical skills to deal with them if they do occur.

At the Emsworth School of Navigation, we see this course as an essential part of modern seamanship, as much as getting your Day Skipper or Yachtmaster tickets.

There is no exam to get stressed about so you can relax and focus on learning from a very knowledgeable instructor.

The Reality: Most Marine Engine Failures Are Preventable

When leisure boat engines fail, it’s rarely because of catastrophic mechanical breakage. Far more often, the cause is something small and avoidable:

• Contaminated fuel or diesel bug

• Air in the fuel system

• Overheating due to a blocked cooling intake

• Flat or poorly maintained batteries

• A worn belt or neglected service item

None of these require advanced engineering to understand — but they do require awareness, routine checks, and a bit of hands-on familiarity and that is where this course comes into its own.

After this one day course, instead of seeing your engine as a mysterious metal box, you start to see it as a set of simple systems working together.

So What Does the Course Actually Teach?

The RYA Diesel Engine Course is designed for ordinary boat owners and crew. No prior mechanical knowledge is assumed. We start with the basics and build practical understanding from there.

How a Marine Diesel Engine Works

Before you can fix problems, it helps to understand what’s supposed to be happening in the first place. The course explains, in plain language:

• The four stages of the diesel engine cycle

• Why diesel engines are different from petrol engines

• What makes marine engines unique compared with land based engines

This foundation makes everything else — maintenance, checks, and fault-finding — far more logical.

The Fuel System: Where Many Problems Begin

Fuel issues are one of the most common reasons engines stop at sea. During the course, you’ll learn:

• The journey fuel takes from tank to engine

• Why water and dirt are such serious enemies

• The purpose of primary and secondary filters

• How air gets into the system — and how to remove it

Bleeding a diesel engine after a filter change or fuel problem can sound intimidating. Once you’ve seen how it works, it becomes a straightforward, step-by-step process instead of a crisis.

Cooling: Keeping Your Engine Alive

An overheated engine can quickly become an expensive problem. You’ll learn how marine engines stay cool, including:

• The difference between raw-water and freshwater cooling systems

• The role of the impeller and why it’s so important

• How blockages happen and how to spot early warning signs

Understanding the cooling system helps you recognise trouble before steam, alarms, or permanent damage appear.

Air In, Exhaust Out

Engines need clean air to run and a clear path for exhaust gases to escape. Restrictions in either can reduce performance or cause failure. The course explains:

• How air reaches the engine

• Why exhaust systems matter for both performance and safety

• What to look for during routine checks

These are often overlooked areas, yet they’re easy to monitor once you know what “normal” looks and sounds like.

The Electrical Side of a Diesel Engine

Even though a diesel doesn’t rely on spark plugs, it still depends heavily on electrics to start and run. You’ll cover:

• Batteries and basic battery care

• Charging systems and alternators

• Belts and their role in keeping systems running

Many “engine failures” are actually electrical issues in disguise. Knowing the difference can save a lot of stress and guesswork.

Routine Checks That Make All the Difference

One of the biggest takeaways from the course is learning what to check, and how often. Simple habits — like inspecting belts, looking for leaks, or checking coolant levels — dramatically reduce the chance of unpleasant surprises.

These checks don’t take long, but they transform you from a passive operator into an active, aware skipper or crew member.

Fault Finding Without Panic

Perhaps the most empowering part of the course is learning how to approach a problem calmly and logically.
Instead of thinking, “The engine’s stopped — we’re in trouble,” you start thinking:

• Is it fuel?

• Is it air?

• Is it cooling?

• Is it electrical?

This structured approach turns a stressful situation into a series of manageable steps. Even when you can’t fix the issue completely, you’ll have a far clearer idea of what’s wrong and how serious it is.

Who Is This Course For?

The RYA Diesel Engine Course is ideal for:

• Yacht owners with auxiliary engines

• Motorboat skippers

• Regular crew who want to be more useful on passage

It’s especially valuable for those who prefer self-reliance and don’t want every engine concern to mean a call to an engineer or a tow back to harbour.

Why Take It with Emsworth School of Navigation?

At Emsworth School of Navigation, we focus on practical understanding, not just theory. We know most of our students aren’t engineers — they’re sailors and boaters who want clear explanations, real examples, and the confidence to apply what they’ve learned on their own vessels.

Our instructor is a qualified engineer who had many years’ service in the merchant navy and sails his own boat in the Solent. He will present diesel engines in a way that’s approachable, relevant, and grounded in real boating situations. You will leave not only with the RYA Diesel Engine certificate, but with a far more relaxed attitude toward the engine space on your boat.

Seamanship Isn’t Just About Sails and Charts

Good seamanship includes knowing how to navigate, handle a boat, read the weather — and look after the machinery that may one day get you out of trouble.

The RYA Diesel Engine Course is one of the simplest ways to become a more capable, self-sufficient skipper in just one day. And the payoff lasts for every trip you ever make.

If you would like to know more about the RYA Diesel Engine course then please call or text us on 07702 842 190 , email us at This email address is being protected from spambots. You need JavaScript enabled to view it. or complete a booking form

AEC 1: How the MCA Approved Engine Course 1 can help you to get into the Superyacht Industry

Starting a career in Superyachts can be daunting but obtaining the right qualifications can significantly impact your chances of success in landing a good job. Among the many certifications available, the Maritime and Coastguard Agency (MCA) Approved Engine Course stands out as a pivotal step for individuals aiming to enter the superyacht industry. In this article we explore why the MCA Approved Engine Course is not only an excellent means of gaining entry into this exciting field but also a strategic move to enhance your career prospects.

Entry into the Superyacht Industry- getting that first job:

Breaking into the superyacht industry can feel like navigating uncharted waters. However, the AEC 1 which is part of a structured career pathway offers a way into this sector. This qualification also helps if you have experience in other sectors of the marine industry by helping to validate what might already be a comprehensive CV which lacks the credibility offered by formal qualifications.

Comprehensive Training:

One of the key advantages of the AEC 1 is its comprehensive curriculum, covering essential topics such as basic engineering principles, mechanical systems, and safety procedures. This knowledge provides a foundation upon which newcomers can build a career. This foundation training includes:

•    The principles of two and four stroke engine operation
•    Construction of engines
•    The role of air in the combustion process
•    The fuel system
•    The cooling system
•    The lubrication system
•    Engine electrical systems
•    Power transmission
•    Hull fittings
•    Fault finding and rectification
•    Safe working practices
•    Bottled gas installations
•    Pollution prevention.

The detailed syllabus is available by clicking onto this link https://www.emsnav.com/mca-courses/mca-approved-engine-course-1-aec-1

The complete MCA document is available here :https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/870191/AEC_1_MCA_Guidelines_2020.pdf

Hands-On Training:

Two training rooms are used. Training Room 1 is a conventional classroom with a whiteboard and projector facilities which your instructor will use when teaching the theory side of the AEC1 course, Training room two is a workshop facility where the hands-on practical side of the course is taught. The engines you will work on include: a working diesel engine, a two stroke outboard motor and a jet ski engine.  Tools and Personal protective equipment (PPE) are provided.

Industry Recognition:

The training centre must be accredited by the Maritime and Coastguard Agency (MCA) before it can offer courses and this requirement ensures that quality is maintained and that any future employer can be assured that you have received quality training from an accredited provider.  The fact that you sat and passed an exam with an accredited supplier will give you additional confidence when working on engines in the workplace.

Industry Requirement: 

Superyachts (and other vessels) are often required to have at least one person with an AEC 1 qualification on board to meet regulatory requirements and so there is an in-built demand for crew with this qualification.

Gateway to Further Advancement:

While entry-level positions may be your initial goal, the MCA Approved Engine Course also serves as a springboard for future career progression since holders of the AEC 1 qualification can serve as

•    chief Engineer on sailing yachts over 24m in length and less than 200gt and 750 Kw within 60 miles from a safe haven
•    Chief Engineer on motor yachts over 24m in length and less than 200gt and l500Kw within 60 miles from a safe haven
•    Act as the Assistant Engineer on vessels over 200gt within 60miles from a safe haven (under the Large Yacht code LY(2)

Career Advancement within the Superyacht Industry:

If you are already working in the the world of Superyachts and are looking for a next step up the career ladder then investing in yourself and upskilling is key to staying ahead in this dynamic industry. Spending five days on the AEC 1 gives you a globally recognised, highly portable qualification that can sit alongside your work experience and help to unlock new career prospects on Superyachts or other working vessels.  

Conclusion:

In conclusion, the MCA Approved Engine Course 1 works to kickstart or enhance the careers of existing and aspiring crew in the Superyacht industry.  Full details of the course including dates and prices can be found HERE

Take your next step on the marine engineer career ladder with the

MCA Approved Engine course 2 (AEC2)

You have already taken the first step and obtained the AEC1 or equivalent qualification and you may be thinking about your next move up the career ladder or possibly a sideways move to a different sector or vessel. In either case the AEC2 will almost certainly have featured quite high in any list of options but you still may not be sure that this is the right course for you. To help you make an informed decision we have written this article which hopefully answers any questions you may have but if you need more information or for a quicker response please call us on 01243 432485 or email us at This email address is being protected from spambots. You need JavaScript enabled to view it.

What is the AEC 2?

The AEC 2 is an advanced marine engineering course designed for individuals who have already completed AEC 1 or possess equivalent experience. This course builds upon the fundamental knowledge already gained and equips you with the in-depth skills needed to diagnose problems, troubleshoot issues, and perform routine maintenance procedures on marine engines and other systems confidently. The reference to “engine” in the course name suggests that the course is only about engine servicing, maintenance and operation but the course is much broader covering other topics including: refrigeration, legislation, pollution control (MARPOL), safe systems of work, electrical systems, hydraulics, fresh water systems and sewage treatment. The detailed syllabus can be found by following the link at the end of this article.

Why Take AEC 2?

There are several compelling reasons why taking AEC2 is a good career move:

• Cross-system approach: The syllabus summarised above may seem broad but from experience you will know that on a modern vessel the effective operation of one system can rely heavily on the operation of another: the reliance of a hydraulic system on the main or an auxiliary engine might be one example where two systems are separate but one (hydraulics) is highly dependent on the other (the main engine). So, in designing the AEC2 syllabus, the MCA consultation with the marine industry has taken this interdependence of systems into account and developed this course to enable you to work effectively and safely across multiple systems and to demonstrate to potential employers that you have obtained this knowledge in an accredited environment.

• Hands-on Practical Training : AEC2 doesn't just focus on theory; the course also incorporates a significant practical component which will be delivered in our well equipped engineering training room. These hands-on sessions will allow you to apply the knowledge you gained in the theory classroom in a safe, controlled environment where you can make and learn from mistakes without causing any harm to yourself or the equipment. Tools and appropriate personal protective equipment (PPE) are provided.

• Employability - Career Opportunities: Although you may have a great deal of experience working on marine engines and systems in your current role, the AEC2 qualification demonstrates to future employers that you hold a recognised qualification that supports the work experience detailed in your CV. The fact that for regulatory reasons many boats are required to have someone with this or an equivalent certificate further increases demand for crew members with this qualification and so your likelihood of finding employment in a competitive labour market is increased.

• Portability: Unlike in-house, employer driven courses which are often quite niche relating to a specific employer’s or specific vessel’s needs, the AEC2 certificate will be in your name and provides current and future employers with third party accredited evidence of your engineering knowledge.

• Lifelong Learning: The maritime industry is constantly evolving, technology is always advancing and the AEC2 provides you with a solid foundation for lifelong learning as a marine engineer

What Qualifications do I need to attend an AEC2 course: You will need to be at least eighteen years old and hold the MCA AEC1 certificate or you will need to show equivalence with the AEC1 through experience and /or equivalent qualifications. There are exemptions under MIN642 and MSN 1904 (you may have seen references to MIN524 but this has been replaced by MSN 1904

Where is the course delivered: The course is delivered in the UK at the Emsworth School of Navigation’s training facility in Emsworth Yacht Harbour on the Hampshire / Sussex borders and is easily accessible by all modes of transport. There is a cafe on site and tea and coffee are provided by us. Shops and other cafes are just a short walk away and we can provide a list of businesses offering accommodation nearby

The School: The School has been in existence since 2008 and is certified by the MCA to deliver the AEC1 and AEC2 courses. Confirmation of our accreditation can be found on the MCA’s website here MCA AEC2 Confirmation of Accreditation to deliver the AEC2 Course:

Your Instructor: Our principal instructor is Martyn who served as an engineer officer in the Royal Navy before working in the Superyacht industry. Martyn’s vast practical experience gained while working on a range of vessels and systems is supported by a thorough knowledge of the theory underpinning the use and maintenance of the systems operating on a modern boat.

Invest in Your Future
By giving up five days you can invest in yourself by taking this course and getting a respected qualification that will support your career ambitions throughout your career in the marine industry. in a course that will AEC2 is an investment in your future career in the maritime industry.

MCA Advanced Engine Course 2 Syllabus: The detailed syllabus can be found here

Full details of the course including dates and prices can be found HERE