“The reliability is the No. 1 thing,” Capt. Jon Stasinos said during a late August run to Provincetown. “They’re quieter engines, and they make the ride better for our passengers.”
The ferry reentered service in the spring after a nearly $3 million repowering during a winter drydock at Gladding-Hearn Shipbuilding, part of the Duclos Corp., Somerset, Mass., which built the Salacia.
“The engines were pretty well worn out,” said Robert Tarrant, BHC’s director of engineering. Installed when the catamaran was built in 2000, they had been overhauled several times and were approaching 40,000 hours. “That coupled with the fact that there have been so many upgrades to engines since 2000 — particularly in the fast ferry market” — propelled the project.
The boat now has four MTU 12V4000M64 Tier 3 engines rated at 1,950 hp each at 1,830 rpm, supplied by Stewart & Stevenson Power Products, as well as two new John Deere 4045 AFM85 powered Tier 3 generators. It also has four ZF Marine 465D reduction gears (1.659:1) identical to the originals and built from scratch, since they were no longer in production.
So, how is Salacia doing? “When we’re running at our sweet spot — about 1,750 rpm, we’re still getting very good horsepower at good vessel speed and the engines are not working as hard,” Tarrant said. Normal cruising speed is about 32 knots. The engines also run cooler because of the triple walled exhaust manifold.
What’s more, BHC expects longer times between maintenance — 15,000 hours for a top end overhaul and 30,000 for a major overhaul compared to 6,000 and 12,000 for the old diesel engines.— D.K. DuPont