Commercial fisherman Tony Guarnaccia repowered his deep sea fishing trawler, the Lady Miriam, with a Yanmar 6HYM-ETE in 2009 and has now clocked an amazing 46,000 hours of operation. That’s an exceptional achievement for a vessel which operates in Bass Strait, one of the toughest waterways in Australia.
The Lady Miriam was built in Tony Guarnaccia’s home port of Lakes Entrance (Vic) in 1980 by the Newman family. This is a heavy steel hull which measures 19.9m loa with a beam of 6.6m and displacement of up to 140 tonnes heavy-ships. Trawling in Bass Strait for up to seven days at a time, in sea conditions with up to 40 knots of wind, demands a tough boat and an equally tough crew.
Originally the Lady Miriam was powered by a large non-Yanmar marine diesel engine. This engine had one major rebuild, but when it started to show signs of age and needed a second re-build, Tony decided that it was time to install a brand new engine.
“I wasn’t unhappy with my original brand of engine,” Tony Guarnaccia said. “However, rebuilding an old engine for the second time was bad business.”
“When I decided to fit a new marine diesel engine, the manufacturer of my original engine didn’t have a marine model in their range big enough. So I researched the market and settled on Yanmar. The Yanmar 6HY series is a big capacity 13.73 litres, 6 in-line engine and is commercially rated by Yanmar.”
The re-power was undertaken in May 2009. The original 6:1 reduction transmission was rebuilt and retained. Similarly, the 60” x 59” Mercado prop was used with the new Yanmar engine powered drivetrain.
Yanmar’s 6HYM-ETE model engine is a purpose built commercial grade marine engine. It includes Yanmar’s latest combustion chamber design named ASSIGN; a system originally pioneered by Yanmar on their large bore, low speed propulsion engines.
This technology, combined with Yanmar’s own mechanical fuel system, delivers impressive fuel consumption results and gives commercial fishermen exceptional fuel economy.
The 600hp (441 kW) twin turbo develops peak power at 2100rpm and is the perfect engine for skippers who demand that their engine runs at full throttle for up to ten hours. The cylinder head is a quad valve design. This Yanmar engine works hard in conditions demanding continuous commercial use. The engine weight is 1385 kgs without marine gear.
Following the re-power, Tony Guarnaccia has been happy with the new lease of life which the Yanmar has given Lady Miriam.
“Fuel consumption has improved by a litre or two per hour,” Tony said. “I have plenty of power now to trawl the heavy nets through the fishing grounds and the Yanmar 6HYM-ETE has been extremely reliable.”
In addition to the Yanmar 6HYM-ETE in the engine room, there is also a 4 cylinder diesel powered generator plus a big 8.3 litre diesel engine which drives the hydraulic pumps and winches. All up, the combined fuel consumption of the three engines is calculated at 53 litres per hour on an extended seven day fishing trip.
While the Yanmar 6HYM-ETE has now logged 46,000 hours of operation, at 38,000 hours a routine top end service was performed in line with Yanmar’s recommended maintenance regime. This is an in-situ service which involves replacement of liner seals, piston rings and a turbo service. The pistons and bearings were inspected and were in great shape.
With a skipper and crew of three on board, Lady Miriam works hard. The Yanmar 6HYM-ETE ticks over 1600 rpm for a speed of 8 knots, and when the throttle is pushed all the way down, a top speed of 9 knots can be achieved.
While the Yanmar 6HYM-ETE engine was installed in Lady Miriam in 2009, Yanmar has since upgraded the Yanmar 6HY series with the Yanmar 6HYM-WTE range with models that develop up to 700 mhp (515kW).