Yanmar Saildrives – The ideal Match for the Multihull Kato


Tony Longhurst is a man of action who has always led a fast life. A retired V8 Supercar driver, water ski champion and now the CEO of the successful Boat Works complex on the Gold Coast, Tony has recently taken delivery of his Yanmar 4JH4-TE powered luxury multihull, Kato.


Kato is an impressive cat. Her vital statistics include a length overall of 18.0m, beam of 8.4m and displacement of 12,000 kgs. In each of the two engine rooms is a Yanmar 4JH4-TE matched to the new-model Yanmar SD60 Saildrive & Gori 3 Blade Folding Propeller. The Yanmar / Gori package pushes Kato along at a remarkable 15 knots under power.

Designed by Schionning Designs in NSW and custom built by Noosa Marine in Queensland over a period of 14 months, Kato is an imposing yet sleek hull. This is a hand crafted hull built from composite materials and without moulds. Through the intelligent application of these composite materials, Kato has the right blend of strength and light weight.

When designing their new multihull, Tony Longhurst and his wife knew what they wanted from their new boat. They were looking for improved sailing performance over their previous multihull. They also wanted to combine great performance with comfortable accommodation and to ensure that the level of fit out and comfort was the best available.

Tony Longhurst and his wife intended to sail Kato alone most of the time on their extended cruises on the north-east coast of Australia and beyond.

Kato 3

The outcome is a customised version of the Schionning G-Force 1800. Kato has been built to sleep eight. The port hull is the guest side of the hull while the starboard side is dedicated entirely to the owner’s suite. All the cabins are spacious, filled with natural light, uncomplicated and welcoming.

Between the two hulls is a spacious bridgedeck which houses the huge lounge and fully fitted galley. Easy open access to the rear deck brings the living area and cockpit together as one.

Every aspect of the design, construction and fit out of Kato was subjected to intense scrutiny; the engine room being no exception. Based on past experiences with Yanmar and further research into the power options, Tony Longhurst decided on the top of the range Yanmar 4JH4-TE engines driving the latest Yanmar SD60 Saildrives.

Kato 2

“We wanted engines that were very dependable, delivered top flight performance and had a good power to weight ratio,” said Tony Longhurst.

“It was also vital that we selected a brand that has a world-wide support network for parts and service. Yanmar was the stand out brand and we remain very comfortable with our decision.”

“Yanmar is a perfect match for Kato. We selected the biggest Saildrive package in the range and I’m glad that we have all that Yanmar power on tap for whenever I need it.”

The Yanmar Saildrive is a purpose designed and manufactured drive, popular amongst owners of multihulls and keelboat yachts. The drive configuration provides a through-hull drive leg directly connected to the engine with no intermediate connection shafts to simplify the installation and reduce alignment issues. The SD60 Saildrive unit installed in Kato has a reduction ratio of 2.49:1.

Kato 6

The Yanmar 4JH4-TE engine develops 75mhp at 3200 rpm. This is a four cylinder, turbo charged engine which displaces1.995 litres. Boasting four valves per cylinder, the Yanmar 4JH4-TE delivers more power with lower emissions. The standard 125 amp alternator produces maximum power for the high electrical demands of cruising boaters.

Rounding out the propulsion package on board Kato are a pair of 3 blade Gori 20” x 15” folding overdrive props.

The 3 blade Gori propeller has a patented overdrive function, a second pitch which can be compared to the 5th gear in a car. The overdrive function can be used when motoring in calm waters or when motor sailing for noise reduction and lower fuel usage. When sailing and the 3 blade Gori propeller is folded, it has the lowest drag of all 2 and 3 blade propellers, fixed, feathering and folding with only 1.4 Newtons of drag at 6 knots. In addition, the 3 blade Gori propeller once folded does not auto rotate, so no shaft brake or transmission lock is required.

While the motoring performance of the Yanmar Saildrive package is remarkable, under sail Kato boasts exceptional performance. In light winds of just 8 knots, Kato recorded a boat speed of 9.8 knots. Under stronger winds of 16 knots, Kato has clocked 24 knots.

The key to the success of this cruising catamaran is the excellent power to weight ratio and a good waterline beam to length ratio. Of course the efficiency of the Yanmar 4JH4-TE, Yanmar Saildrive legs plus the sleek Gori folding props, also contribute to the success of this superb cat.

Kato 4

Kato 5