When the syndicate owners of Antares, a 2017 Riviera 5400 Sport Yacht, decided it was time to renew the vessel’s powerplants, the project became far more than a straightforward engine replacement.
Undertaken by the RMC Service Centre team, the longblock project involved careful planning, extensive refurbishment work and a complete recommissioning process designed to prepare the yacht for many more years of reliable cruising.
At the heart of the project were two new Volvo Penta D11 longblocks. To access and remove the existing engines, sections of the cockpit floor and tender garage were removed, allowing the team to safely extract the original engines and transport them to the workshop.
From there, attention turned to preparing the new engines and refurbishing a range of components that would be transferred across.
Old Engines
New Engines
Rather than simply replacing the engines, the team took the opportunity to restore and refresh critical systems while access was available.
External engine components were removed, cleaned, inspected and refurbished before being fitted to the new longblocks. New injectors were installed, valve adjustments completed and components prepared for reassembly.
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The cooling system also received significant attention. Coolers were dismantled and acid cleaned to remove years of scale and build-up, helping restore optimal seawater flow. New O-rings and anodes were fitted, components were refinished and pressure tested, and everything was prepared for installation.
It’s the kind of behind-the-scenes work that may not always be visible, but plays an important role in long-term reliability.
With the engines removed, the vessel’s generator was also extracted, creating an ideal opportunity for preventative maintenance.
The generator underwent a thorough inspection and refurbishment, including repairs to corrosion on the bell housing, rectification of saltwater leak issues, valve adjustments and routine servicing. By addressing these items during the project, the team could return the vessel to service with greater confidence in both propulsion and onboard power systems.
As refurbishment work progressed, the new engines steadily took shape.
Once prepared, the Volvo Penta D11 longblocks were carefully lowered back into the Riviera 5400 Sport Yacht, along with the generator. Reinstallation required precision planning to ensure every system was correctly aligned, connected and ready for commissioning.
With the vessel reassembled, the final stage began.
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Comprehensive diagnostic checks were completed across the engines and supporting systems before sea trials commenced.
The results were exactly what the team had hoped for. System monitoring confirmed the engines were performing correctly, with no faults detected, and sea trials demonstrated the vessel was operating as intended.
For the syndicate owners of Antares, the successful completion of the project means renewed confidence for the seasons ahead.
As Queensland’s boating season approaches, Antares is once again ready to head north and enjoy the adventures that lie ahead—powered by a renewed foundation and backed by the expertise of the RMC Service Centre team.
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