Yanmar Re-Powers Harbour Commuter Ferries

Rarely does a single commercial vessel go through such a transformation as the “Harbour Cat”, operated by Fullers of Auckland. But to transform the “Tiger Cat” ferry and then repeat the exact process on “Harbour Cat” confirms that the Yanmar 6HY-WET repowers have been an unqualified success.

Constructed and launched as an 18m ferry, the “Harbour Cat” worked across various waterways in NZ until she wound up in the Fullers Auckland commuter fleet. Somewhere in her chequered past, the vessel was lengthened by two meters and re-powered. But Auckland commuters regarded her as a noisy and Spartan commuter.

Fullers Auckland withdrew the “Harbour Cat” vessel from the commuter run and handed her over to the team at Oceania Marine for a complete refit. This began at the keel, working all the way through the vessel. This was to be an extensive job by any measure, leaving no area of the vessel untouched.

Having already undertaken a similar refit to their “Tiger Cat” ferry, also installing the same Yanmar 6HY-WET engines, Fuller’s “Harbour Cat” received a similar makeover. This involved ripping out all machinery, removal of everything in the engine room, air conditioning systems, carpet, seating, steering system, even the glass in cabins. Structural repairs were executed, while air intakes and exhausts were replaced. Bob Makin was the “specify and project manager” for both projects, so brought great experience to the task.

Fullers Ferry

Photo courtesy of Keith Ingram and Professional Skipper magazine

In the engine room, a fresh pair of Yanmar 6HY-WET 600mhp marine diesels were fitted. Yanmar’s 6HY-WET model 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 provides commercial operators with excellent fuel savings.

The 600hp twin turbo (441kW) at 2100rpm is the perfect engine for those who require their engine to run at full throttle for extended periods. The cylinder head is a quad valve design. In this configuration, the Yanmar 6HY-WET excels in conditions demanding continuous commercial use.

Coupled to conservatively rated 500 series ZF reduction transmissions, spinning five blade counter rotating Tiger props, the “Harbour Cat” also received a complete new drive line.

Whereas the old “Harbour Cat” was not the most popular vessel amongst commuters, post re-fit she is a totally different beast. The twin Yanmar marine diesels emit a determined growl from the engine room, but the on-board noise levels are a marked improvement on the previous engines and the engine room fit out.

The new Yanmar 6HY-WET marine diesels in their white livery look the part in a sparkling new engine room. Once fired up, this cat is ready to pounce. Easing the

throttles forward, the Yanmar engines punch out 600 mhp a side, quickly pumping the “Harbour Cat” up to service speed of 23 knots.

Post re-fit, the once tired commuter ferry is now smart and well presented. The skipper, Lane Van der Linden, rates the vessel easy to operate.

With the extensive re-fit program completed, the vessel’s service life has now been significantly extended. It has also proven that this “half life” refit is a practical and economic option for lengthening the service of hard working vessels that typically put in up to 4,000 hours a year.

While the Yanmar engines have played their part in the transformation of the “Harbour Cat”, the all embracing re-fit program has demonstrated that the commercial life of a vessel can be greatly extended. The extensive application of new, high quality replacement marine equipment means that Fullers of Auckland have two fully refurbished vessels destined to operate efficiently for many years to come.

Fullers Ferry1