The refit market is becoming increasingly important for MarQuip. Thanks to our broad experience in this field, we know that refits require a very different approach to new builds.

The refit market is becoming increasingly important for MarQuip. Thanks to our broad experience in this field, we know that refits require a very different approach to new builds. From merely changing silencers to overhauling the full exhaust system of the main engines or generators, we have always delivered to the satisfaction of our customers. One of our specialties is swapping the exhaust system for an environmentally friendly alternative.

Our work on refit projects covers a full range of activities such as consultancy and system checks, including insulation and installation, in order to see what needs to be replaced on board. MarQuip’s highly practical approach makes us an exceptional partner in refit projects. We are ideally placed at the fulcrum of decision-making for the whole project, ensuring short lead times. In addition, our service team provides high-quality support to captains and crews both during and after a refit.

While every yacht is unique and circumstances can vary widely, the ideal process would be as follows:

1. Preparation and information phase

As soon as we receive a request for a refit, MarQuip specialists start gathering all the relevant information about the boat. We ask the new client for photos, specs and accurate drawings. If drawings aren’t available, we use one or more special procedures and techniques to prepare the refit. These include:

  • making a 3D scan of the engine room
  • setting up performance data sheets for the engines
  • back-pressure measurements
  • carrying out profiling of the wave/hull profile via tank tests or an actual on-site wave pattern measurements

If the yacht is above 500 GT and the refit involves fitting new engines with a higher power output, it’s important to keep in mind that this will cause it to fall under IMO tier III regulations in terms of nitrogen oxide emissions (if the new engines are equivalent to the old, IMO tier II can continue to apply).

2. Checking on board systems and trial run

Once we’ve received all the information pertaining to the boat from the client, we can build a complete picture of the current state of the vessel and how well its various systems are functioning.

3. Preparatory conclusions

The thorough preliminary work helps us establish the relevant values and make conclusions about what we need to do to solve the issues and upgrade the boat. This is where we formulate a thorough plan of approach.

4. On-site kick-off meeting

The next step is organising a meeting at MarQuip with the yard, the captain and the crew. We discuss our proposal and ensure that everyone is in agreement with our recommended approach.

5. Engineering, design & drafting

Once all the preparations are complete and the owner has signed off on the plan, MarQuip takes care of the actual engineering, design and drafting work.

6. On-site process monitoring meetings

If required by the owner or required by the particular circumstances, we can organise meetings at MarQuip during the refit process to discuss or demonstrate the progress.

7. Delivery of engineering package & drawings

The following step is delivering the design and engineering package and drawings to the owner’s team.

8. Pre-production approval

Before MarQuip begins the production of the various components involved in the refit, we request a formal approval from the owner.

9. Production of hardware

Once the preparation phase is complete and the engineering & design plans are finished, MarQuip proceeds to manufacture the equipment for the refit.

10. Fitting of hardware

In the next step, the components are installed on board by the yard or by MarQuip, depending on the owner’s and the yard’s preference.

11. Commissioning and sea trials

The final stage of the refit process involves commissioning, testing and sea trials. MarQuip provides a comprehensive guarantee for perfectly functioning systems.

12. After-sales service and customer satisfaction

We supply a wide-ranging warranty and after-sales service to ensure that our refit clients are happy with our work. At MarQuip, we know that the satisfaction of the people for whom we work is our best marketing strategy – and our track record has led to many clients becoming brand ambassadors.

Replacement of exhaust systems
While a well-built exhaust system has a long lifecycle, there are many factors that can shorten its lifespan. MarQuip is the ideal partner for your engine refit in cases where the exhaust needs replacing. Whether you need a completely new system because new engines or generators are being installed, or just a partial adjustment of the capabilities of the current system, we will find the best possible solution for your refit.

On-site project management
Refits are very different from new builds. They have a complexity of their own and require many parties to come together. In some cases it can be desirable to deploy an on-site project manager for a refit of the exhaust systems. A MarQuip manager can ensure a smooth and correct start-up of the project and can, if necessary, take over commissioning and testing.

Segmented silencer
The most frequently replaced part of an exhaust system is the silencer. Unfortunately, this is often a central part in existing exhaust systems, and as such is large, heavy and fitted in a central location in the engine room (often directly above the engine).

In the past, they could only be replaced by making a hole in the hull, removing the old silencer and installing a new one (space permitting). This took a lot of time and cost a fortune in project costs for all parties involved. MarQuip has invented a perfect new solution for this issue: the segmented silencer. This can be brought onboard in separate parts based on the available space and then mounted in the engine room. The upshot is a short lead time of just two weeks and significant cost reductions.

You can choose to have the previous silencer dismantled and the new one fitted by our experienced refit team. If you already have capable construction welders at your disposal, we can provide you with a comprehensive manual, instructions and welding material. In both cases, it is important that MarQuip be invited to carry out commissioning and practical tests after the new silencer has been installed in order for the full warranty on the operation of the silencer to apply.

Have a question?

Jeroen van der Matten

General manager

Techniques we use

  • Back pressure control

  • Noise attenuation

  • Anti vibration control

  • Exhaust cooling control

  • Emission control

  • Exhaust Heat Exchanger

View techniques

Have a question?
Contact our consultants.

Need a new exhaust system for your yacht or have a general question? Let us know and call us on +31 (0)78 681 09 75 or email us on

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