Melbourne River Cruises: Overhaul Hydraulic Propulsion System (Yarra Countess)

The Yarra Countess – Melbourne River Cruises’ premier cruise boat – is driven via a hydraulic thrust system consisting of four Rexroth A4VG 71cc axial piston transmission pumps and two A4FSP 250cc axial piston thruster motors.

After years of high duty service, the entire system had fallen to below 80% efficiency resulting in speed and heating issues preventing the boat from making its regular crossings from Southbank to Williamstown.

With the system in major need of overhaul Hydraulics Australia accepted the challenge, ordering all the necessary components, a large portion of which from Germany, prior to commencing the repairs and ensuring a minimal time out of the water. With all the necessary components on hand the boat was then placed into dry dock and all pumps and motors removed.

With the clock ticking all six units were given complete overhauls back to original manufactures specifications, including replacement of major rotating groups and tested at full flow and maximum operating pressure of 300 bar.
The system was then drained and cleaned with all filters changed before re-installing pumps and flushing. Last but not least the thruster motors were finally installed and the vessel was back in the water and commissioned three days ahead of schedule.