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Chuck Gould Chuck Gould is offline
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First recorded activity by BoatBanter: Jul 2006
Posts: 3,117
Default GB going to Zeus drives (pods) on a new 2008 model

On Aug 28, 7:42?am, HK wrote:
Chuck Gould wrote:
On Aug 28, 3:25?am, HK wrote:
Chuck Gould wrote:
Grand Banks Yachts today announced plans to release an
extraordinary new addition
The two-stateroom 41EU will be the first Grand Banks to utilize the
Zeus Propulsion System from
Cummins MerCruiser Diesel, a revolutionary new propulsion system
launched in 2006.
Wow...reposting of an entire commercial PR release. Is this that idiotic
forward facing prop system?


Relax, Harry.


This doesn't concern you- it's something that people who actually use
a boat or may be buying an inboard boat in the future might find
interesting.


No, it has nothing to do with the Volvo IPS system. (Which is far from
idiotic). Zeus drives face aft. They incorporate counter rotating
props, and each of the two pods can be vectored independently.


That's the plastic boat I want, the one with two huge chunks of metal
full of gears and complicated machinery hanging down from the bottom,
where you can't see any part of it. Now, on a steel-hulled displacement
boat built to commercial standards, and where divers and competent
maintenance is available at shipyards, and where money is no real
object, well, maybe.

It's one thing to ding the bottom or even a reef with a standard
inboard...you might get get away unscathed, or you might damage a prop
blade or, well, sure, worse things can happen. But the kinds of repair
bills "Zeus" will enable...whoooo-hoooooo.- Hide quoted text -

- Show quoted text -


I know you're not really familiar with the architecture of anything
larger than your fishing skiff, but if you would read before you react
you would learn from the press release that the props and pods are
protected in two different ways. First, there is a skeg on each that
should prevent serious damage from a soft grounding. Second, pods
mount in prop tunnels, additionally reducing the amount of exposed
surface.

A couple of other things to know, that aren't included in the release:
Cummins *recommends* mounting the pods in tunnels or depressions so
the forward facing tips extend no deeper than the keel of the vessel-
and that will allow the keel to help protect the props. The skeg is
designed to sheer, if necessary.

Most twin engine inboards will have for more running gear exposed,
considering struts, shafts, etc, than is exposed with the Zeus pod.
When striking a swamped container, deadhead, etc at high speed with a
traditonal twin engine inboard there is a risk of taking out a strut
and opening a hole of maybe a square foot or more below the waterline.
(Mayday!) The Zeus pod, like Volvo's IPS, is designed to sheer cleanly
in the event of an extremely serious impact. You will lose your
$20,000 drive but maybe save your $2,000,000 boat.