Oracle expedition vessel repower for the serious job of retirement off Western Australia
by Power Equipment 6 May 2020 07:58 PDT
MV “Oracle” has recently undergone rejuvenation with two new Yanmar 6CXBM-GTs and is prepared for broader expeditions and an adventurous retirement for its seafaring owners © Power Equipment
When it came to the serious business of retirement after a lifetime of hard work on the water, Lynn and Peter Mouchemore decided to repower their impressive expedition vessel MV Oracle with new Yanmars for their frugal and reliable promise into the future.
It is not every day that you see a 24.5 metre Westcoaster - originally launched in Western Australia in the year 2000 as an America's Cup support vessel - taken out of its own virtual semi-retirement and setup as a home-away-from-home for a couple who love their time with family on the water.
With berthing for 18 people aboard, huge outdoor galley (the "LG - Lynn's Galley" as it is affectionately known), three tonne crane, 300kg/day ice machine, marlin board and fully enclosed wheelhouse, she is a true expedition vessel with capability for comfortable living and huge range.
Peter's original plan was to build a large catamaran and have that as a launchable vessel from their home base in Dongara, but a change of plans saw a four-year search for the right vessel instead.
Oracle had been used for charter in New Zealand after its America's Cup duties and had ended up in Queensland for another two years after that in which she clocked up some 16,000 hours of engine operation on each of her original engines. She had been used primarily as marina-based accommodation at a yacht club for around five years following those chartering days and her previous Yanmar powerplants had suffered from a lack of use and marine care in later years.
Hence Peter decided to change out the original 20-year-old Yanmar 6CX-GTYE (360hp @ 2600rpm) engines with new 6CXBM-GT M rated (400hp @ 2,500rpm) power and ZF286A 2.5:1 transmissions.
With a hefty dose of marine experience himself, (Peter was a commercial fisherman for 57 years), he had a few ideas on upgrades for Oracle and the refit.
"I wanted to keep a similar engine to the mains that had been running in the vessel, so we went for the simplicity and reliability of the 6CXBM-GT engines, close to the original horsepower," Peter said.
Exhaust upgrades for both the main engines and auxiliary power were part of a six-figure upgrade for Oracle.
Working with Nick Marsden from Power Equipment's Fremantle office, the 6CXBM-GT M rating engine was chosen.
"They are definitely quieter," says Peter of the new Yanmars powering Oracle, "and both of my sons agree."
"Fuel economy is probably close to the old Yanmar setup and we're getting 10 knots for probably close to 33 litres per hour (combined)," Peter says.
Understanding the value of cruising revs to propel Oracle's 42 tonnes and to take advantage of the 6CXBM-GT's sweet spots in torque curve, (which run between around 50 to 80 per cent of engine speed in these Yanmars), Peter opted for a change in propellers to capitalise on the engine's most economical running speeds.
"She had been running a five blade propeller, which gave her a couple of extra knots top speed," Peter explained, "but they were pretty thin so I changed them for a four blade prop with more pitch (Nakashima 32inch diameter X 28inch pitch) which gives us 10 knots at economical revs".
While Oracle tops out speed-wise at 15.6 knots, her range can be extended hugely at 8.3 knots with the Yanmars running at only 1,300rpm. Holding 9,000 litres of diesel aboard, Peter and Lynn's Western Australian coastline is very much their proverbial oyster! (At the lower cruising speed, the expected range of the vessel exceeds 2,250 nautical miles).
Peter says the four-blade prop upgrade gives more positive handling at lower speeds too - a nice help with quiet Yanmars and no vibration felt from the wheelhouse.
"The engines are solid-mounted using the original bedding setup, but there is no vibration. You feel nothing and hear little at the wheel," Peter said.
This shouldn't be surprising, given the 7.4 litre 6CXBM-GT Yanmars are able to deliver their power smoothly thanks to Yanmar's patented combustion system and new fuel injector design, high-performance turbo that delivers less turbo lag and high-efficiency intercooler.
The 6CXBM-GT is part of Yanmar's purpose built range of marine engines aimed at commercial applications and not only delivers minimal fuel consumption across a wider speed curve, but caters for multiple professional activities at sea. Professional fishing, pilot boats, patrol boats and fishing charter vessels are some of the applications where this engine model has excelled.
While it is a fully mechanical engine (a preference for Peter who does most of his own maintenance), this user-friendly engine is still Tier II compliant with lower NOx emissions - making them environmentally friendlier too.
Large inspection windows on the side of the 6CXBM-GT block even allow in-situ replacement of pistons if ever necessary - although with under 100 hours of running time up so far on Oracle's new main engines, that kind of maintenance will be many years away.
Part of Oracle's refit saw new auxiliary power installed also with two new Mase Mariner 2510T 25kVA three-phase silenced generators. These units are powered by the legendary Yanmar 4 cylinder direct injection engine model 4TNV84T, one that is also well known for its frugal fuel usage, low noise, high reliability and long life.
"The Mase boxes are brilliant" says Peter, "I've got 169 hours run up on them so far and I do my own servicing on them also."
As with most boat operators with a commercial background, Peter is serious about maintenance and says he currently holds "around four years' worth of maintenance consumables and filters aboard".
"Most 'wood ducks' (Peter's friendly term for boat owners who know or care little about vessel maintenance) just don't understand the importance of regular maintenance - it's not an option, it's a necessity," quips Peter.
Yanmar gets the nod for penultimate sea adventures for Peter and Lynn
Peter and Lynn cruised in Oracle for around nine months across two extended trips before deciding on her four and a half month refit at Northport Shipyard in Fremantle. WestJet Propulsion and Peter himself worked on the engine installations.
Oracle's 24.5 metre length and 6.5 metre beam provide for a lot of living area aboard and significant inventory of equipment. Spending around $650,000 on her on top of the original purchase price, Peter says Oracle owes him in the order of $1.5million.
"The Yanmar price was competitive however and their fuel economy is great," Peter says.
"We've got all we need onboard, including Foxtel and all the free-to-air television, a bar and plenty of refrigeration," Peter says proudly.
Peter and Lynn's sons have continued their father's (and his forefathers') proud tradition of fishing off Western Australia, with Peter still helping his sons on board their 18.6 metre Conquest in their own commercial cray fishing season work.
"I'll sometimes go with them and maybe drive the boat between pots just to help them out," Peter says.
This season they parked Oracle up at the Abrolhos Islands group, near one of the boys' preferred fishing grounds north west of Geraldton on the mid-Western Australia coast.
With his own lifetime of fishing behind him, Peter's sons represent a sixth generation of fishermen in the Mouchemore lineage.
Peter fished for sharks off Tasmania for a number of years, (in a 65 foot Fairmile), like his own father and chased both crays and sharks off Victoria before following uncles to the more lucrative - and in Peter's view better managed - fishery of Western Australia in the late 1970s. Among the innovations Peter's relatives introduced to fishing Australian waters was the fact that his uncles brought the first echo sounder to Western Australia in the 1950s.
Oracle is expected to range waters from Quindalup on the southern end of Western Australia's coast to perhaps the Kimberleys if Peter and Lynn are feeling adventurous in their retired maritime months on the water each year. The beautiful Shark Bay inlets are also expected to be a regular anchorage.
Power Equipment has been proud to supply the power for Peter and Lynn's "home-away-from-home" Oracle and it is certainly a vote of confidence in the Yanmar product to have someone of Peter's experience welcome the brand into his penultimate seagoing adventures.