Kubota Z482 (13hp) marinization

[danielb]

Hi,
Here's my situation:
25.5 foot, 2 ton, racer/cruiser fibreglass yacht needing repower. (In New Zealand - that's the one below Australia for the geographically challenged)
Problem:
Low budget!

I currently have an MD5B volvo with MD110S sail-drive, which is quite ancient and am thinking it will need replacement sooner rather than later. Having done my research I found that Beta and Nanni both supply an ideal light engine with perfect output (couple extra hp over current) based on the Kubota. Whats more, both offer a adaptor to mate up to the existing sail-drive which I very much want to retain. Also the standard gearing can be used, as the newer engines put out their higher power at higher RPM (Power/RPM curve same as Volvo, just longer).
The catch is the cost.

The above options are close on 10k NZ dollars (about 5k USD).
I have recently spotted the standard Kubota Z482 for under $5K NZ (about 2.5k USD). So my natural question is, should I attempt marinization myself.
I am fairly capable with motors, having done a few partial rebuilds etc, so don't mind tackling the labour myself.
The questions are:
Will I save reasonable money?
What is needed outside the obvious, like water-water heat exchanger (current engine is raw water cooled), custom exhaust manifold pipe with water injection point (basic, compared to bigger engine systems), and a custom adaptor to the sail-drive/gear-box?
At the end of the day, what differs from the off the shelf Z482, to the Beta marinized version?

Look forward to some knowledgable replies!

[jff]

Diecon engineering in Brisbane does a kit for A$2350 +617 3390 8190
info@diecon.com.au

I have no experience or affiliation with them, just found them while doing some research on building a dc genset

cheers

John