Seawind 1000 cavitating with Honda Engines

[shane malone]

no difference in shaft length you can add extension kits if needed or install jack plates to lower them a little more

[DotDun]

Cavitation or ventilation? There is a big difference.

[sailjumanji]

You probably mean ventilation - whereby the props suck air down around them and spin. I have the Yamaha 9.9's, and ventilation is only a problem when motoring directly into the wind and waves, with the boat poorly loading in the ends and causing it to hobby horse. Never an issue in a mild sea. A problem though motoring against 20 knots and three foot chop, in a confined area like the ICW. Otherwise, you can sail and its not a problem.

I did install Power Thrusters though, which is a half-moon stainless shield that helps prevent air from being sucked down into props. Also does a better job directing thrust than without. Also, what we found is that you need to have the motors fully down, and even tucked under a bit (forward of vertical) if possible. For most of the boats, that was all that was required.

You can't put a jack plate on these. There is a heavily-built bracket that the motor attaches to for swing up and down. The tilt mechanism on the motor is never used. The motors are in wells.

The Hondas are not really know for high thrust, like the Yamahas. Although Seawind has them as standard on the 1160 Lite, I think most people opt for the Yamaha option.

[smj]

Here's a link to the Power Thrusters. http://www.powerthruster.com
We have a single Honda 15 on our cat and I was a little worried it wouldn't have enough thrust. Shouldn't have worried as the thrust is spectacular!

[thinwater]

I believe the Yamahas have a larger prop that is geared lower. That reduces both cavitation and ventilation.

[sailjumanji]

Originally Posted by thinwater

I believe the Yamahas have a larger prop that is geared lower. That reduces both cavitation and ventilation.

Yes, it is a high thrust model.

[catsketcher]

If you have the choice, go for Yammies. We had a Honda 25 on our cat and it was a very nice motor with a problematic bottom end , small prop and high gearing. It got stolen and was replaced with a Yammies 25. No faster in a calm but three times the thrust in reverse and much better on any breeze. I now have twins, both Yammies and would never go back to A Honda. Cheers

[44'cruisingcat]

Are they high thrust props? While Honda doesn't do the 3:1 gearbox and big props of the Yamaha HTs, they do have "powerthrust" props, which have lower pitch, less cup, and greater blade area. They also work equally well in reverse.

For the 15, the prop should be 10" * 6 3/4".

[sailjumanji]

Maybe you can get one of the moderators to move this to the multihull forum. It's currently posted in monohull sailboats.

[Olddan1943]

Originally Posted by catsketcher

If you have the choice, go for Yammies. We had a Honda 25 on our cat and it was a very nice motor with a problematic bottom end , small prop and high gearing. It got stolen and was replaced with a Yammies 25. No faster in a calm but three times the thrust in reverse and much better on any breeze. I now have twins, both Yammies and would never go back to A Honda. Cheers

Sort of nice when something you were thinking about replacing gets stolen?
SMIRK

[shane malone]

Not all jack plates are the same here is a model that would fit within the sea wind in the box it will allow you to just motor from standard height down to 4 inches Model numberJPL4000 it probably weighs less than 20 pounds in sales for about $175

[Ramona]

Make a pair of Korts nozzles for the outboards.

[KiminAK]

Originally Posted by sailjumanji

Maybe you can get one of the moderators to move this to the multihull forum. It's currently posted in monohull sailboats.

Oops, my bad. I'll ask one of the mods.

[a64pilot]

Originally Posted by Ramona

Make a pair of Korts nozzles for the outboards.

That is actually very difficult.
The Kort nozzles you see on almost all Scuba scooters was apparently originally designed with the aid of a Cray Supercomputer back in the day. Shrouding a prop is one thing, an actual Kort nozzle another.
There are prop protectors made for lifeboats and some people who care use them in Manatee areas, they are shrouds, be a whole lot easier to buy a product for most than making your own.

[Bean Counter]

Are you talking the PropGuard
For Your Outboards & Stern Drives - Prop Guard propeller guard