Vessel Revelation, a 55ft Conquest hull used for the primary purpose of rock lobster fishing on Western Australia’s mid coast was due for major overhaul. Powered originally by a MAN D2842LE401 V12 800Hp @ 2100rpm, options for rebuild or repower were explored. The Doosan V12 V222TIM 800Hp @ 2100rpm is an excellent option for repower because of its many similarities to the MAN, whilst offering a very price effective solution both in regard to initial purchase price and the low cost of installation. Given the high costs of operating in the fishing industry, purchasing and building a new vessel was just not an option due to budget, especially considering Revelation is still in excellent seaworthy operating condition. Therefore providing a new powertrain of engine and gearbox will offer the owner a very cost effective solution to allow Revelation to remain reliable and commercially operational for many years to come.

A new Doosan V222TIM Medium Duty 800Hp @ 2100rpm V12 engine was chosen along with a new ZF 500 gearbox in a 2.625:1 ratio to provide the new powertrain solution for Revelation. The MAN LE401 was removed from the vessel without issue, however where it gets very interesting is in the similarities to the Doosan V222TIM which therefore allow for a very cheap engine changeover installation due to the minimal modifications required. The MAN and Doosan share a similar engine block, which allow for the engine feet to be removed from the MAN V12, and will bolt directly onto the engine block on the Doosan V12. By doing so, the Doosan will bolt directly onto the existing engine beds of the vessel without need for costly re-engineering of engine beds. A new front engine bracket was fabricated in this instance to hold the PTO pump, deck wash pump and the power steering pump. The existing exhaust system can be reused from MAN to Doosan and two 100mm adaption flanges were built to allow the existing MAN turbo outlet flange pattern to bolt to the new Doosan holset turbo 4 bolt outlet pattern. The Doosan turbochargers finish 100mm shorter compared to the MAN which mean the adaption pieces fit in perfectly meaning no further exhaust changes were required for vessel Revelation. The water pickup for the Doosan V222TIM is in the front left corner of the engine, so the sea strainer for Revelation was moved to ensure adequate sea water availability to keep the Doosan cool. The Doosan V222TIM was installation was conducted by Lighthouse Engineering, Geraldton. Director Paul Minissale described the repower as a “quick and painless installation”. The fuel lines, battery cables and morse throttle cables were also able to be reused further saving cost. Revelation’s downtime siting on hardstand during the changeover process was minimised because of the quick engine changeover and minimal engineering works required. Revelation was then available to carry on working without being out of action for a long period of time.

Sea trials of the new Doosan V222TIM went extremely well. Revelation was designed and built for heavy load applications and the Doosan, coupled with the ZF 500 2.625:1 ratio gearbox allow for the vessel to perform consistently at both cruise and top speeds regardless whether the vessel is running light ship or loaded up completely to heavy ship rating with pots on the back deck. The Doosan V222TIM now pushes the vessel through the water with ease. At present Revelation sits comfortably at 15 knots at 1800rpm and a top speed of 21 knots at 2100rpm. Revelation still has the opportunity for propeller adjustment to maximise the cruise and top speeds attainable, but for now the owner is extremely impressed with the Doosan V222TIM. Recently departing for a day trip from Geraldton to the waters of the Abrolhos Islands, working in the Abrolhos waters and then steaming back to Geraldton, covering 65 nautical miles in one day, Garry, Revelation’s owner was “pleasantly surprised how little fuel I used”. The Doosan V222TIM offers a reliable and cost effective solution to repowering commercial vessels.

Statistics
Vessel Make Conquest 55
Old Engine MAN D2842 LE401 V12
New Engine Doosan V222TIM
Horsepower 800Hp @ 2100rpm - Medium Duty
Gearbox ZF 500 2.625:1 ratio
Cruise Speed 15kn @ 1800rpm