Beating the barnacles

What started as a potentially dangerous breakdown caused by a single barnacle has resulted in a New Zealand business developing a world-first product.

In the summer of 2000 Martin Duytshoff was at Great Barrier Island aboard his Genesis 32 powered by twin 150hp Volvo sterndrives. One of the legs seized, forcing the engine to be shut down.

"We had to flag the rest of our holiday and limped home on our remaining leg at 9 knots, a vast difference from our normal cruising speed of 25 knots," he recalls.

"It was fortunate the weather was good and the sea calm because it would have been a different story in big seas.

"As it turned out we got back to Sandspit and called our Volvo service agent. His diagnosis was prompt and spot on - a hole in the sternleg bellows caused by marine growth that let the water in and resulted in bearing failure."

That puncture in the bellows resulted in a bill of $2000 and set Duytshoff on a search for some way of preventing the problem from recurring.

Service centre suggestions included painting the bellows with anti-fouling or covering them with a coat of lanolin. These proved both temporary and unsuitable.

What followed was a period of serious international research in an effort to find a product that would stop the growth of barnacles and oysters on stern drives that are permanently moored in salt water. The warmer the water, the worse the growth.

A 25-year veteran of the New Zealand Fire Service in Auckland with a wealth of experience in and on the water, Duytshoff has a string of qualifications that helped him in the quest for a stern leg salvation.

He has taught superyacht skippers and crew fire-fighting and breathing apparatus techniques at Mahurangi Technical Institute and also works with Specialist Paramedical Services for special events and for VIP visits. He likes a challenge.

The family now lives at Kawau Island, where Duytshoff formed Barnacle Busters. The company offers a solution that works for Volvo and Mercury stern drives. Made from a special imported synthetic material it is an outer sleeve that prevents the growth of barnacles and oysters.

To prove that it works, the prototype Protector was fitted to one of the fleet operated by Reubens Water Taxis out of Kawau. After 12 months and 1300 hours the bellows were crustacean-free.

Taxi operator Reuben Zylstra was an immediate convert. His seven boats were given the Barnacle Busters treatment and the Volvo legs on the $200,000 newest addition to his fleet were given the Duytshoff treatment before going into the water in February.

Meanwhile, the inventor is testing the Protector on other in-the-water components and models of stern drives. He is introducing it to Australia, where the company has organised a test on a Noosa Cat operating out of Yeppoon and has stockists on the Queensland Coast.

"On a promotional trip to Sydney late last year a Volvo dealer showed me a set of oyster-encrusted bellows that had sunk an 11m boat that had been leaking water through damaged bellows," Duytshoff says. "Evidence like that, and the insurance claims that follow such incidents, helps convince even the sceptics of the need for our system."

Because the Protectors are inert and contain no chemicals they are environmentally friendly and cannot harm the mechanical components of the sterndrive. Volvo Australia has allowed them to be fitted to new sterndrives without affecting any of the component warranties.