Honda 25s on a Seawind 1000?

[Jerry Woodward]

The Seawind 1000 is currently at the top of my list for a used catamaran for Caribbean cruising. There is one on Yachtworld with Honda 25s instead of the Yamaha 9.9s. My understanding is that the high thrust 9.9s are optimum for the weight and speed and that there is no gain by increasing the HP. In fact, it might be a negative in terms of fuel economy. On the other hand, why would someone go to all the trouble of replacing the 9.9 with the Honda 25s if there were not some advantage? Perhaps more power when you really need it in a strong headwind or current? Other positives to me are the hull extensions, a bowsprit, and an extended polycarbonate bimini. The bow thruster seems silly, but is probably not a negative. I would love to hear some Seawind owners weigh in.

Thanks

[Cheechako]

Being an outboard you can always change it later. There's a lot of windage on a cat. Maybe someone else knows but I'm not sure with one 10 hp you can turn it thru the wind in an anchorage with a some wind blowing...?
The 25 may have been the first attempt to make the boat turn thru the wind.... and the bow thruster the final attempt...
if it were mine I think I would have went for two 9.9's one on each hull....

[Jerry Woodward]

Originally Posted by Cheechako

Being an outboard you can always change it later. There's a lot of windage on a cat. Maybe someone else knows but I'm not sure with one 10 hp you can turn it thru the wind in an anchorage with a some wind blowing...?
The 25 may have been the first attempt to make the boat turn thru the wind.... and the bow thruster the final attempt...
if it were mine I think I would have went for two 9.9's one on each hull....

I believe there are two 25s. You're right, I should be able to change them, unless significant mods were made.

[Cheechako]

Originally Posted by Jerry Woodward

I believe there are two 25s. You're right, I should be able to change them, unless significant mods were made.

Oh good... I thought you were saying it had one engine!

[Factor]

Pointless waste of money putting the 25s on. The 9.9 yammies (have to be the high thrust gearbox four strokes) do just fine.

[Boatguy30]

Pay a deposit, do a seatrail. Might get 10-11 knots when you want it and an economical cruise on single engine.

[tomfl]

My Seawind 1000 with one meter sugar scoops hits about 6.8 maybe 6.9 in flat water and no current. A very similar boat with four foot sugar scoops was hitting 7.1 or so under the same conditions. Motoring into a 12-15 knot wind and a three knot current I could hit five knots in light 2-3 foot seas.

I suspect the 25s would be an advantage against wind and current, but I thought the whole idea was to pick the right weather window and avoid the bad stuff.

In any case you want the long shafts high thrust mods and I am not sure you can get that on the 25 Honda.

In any sort of seaway boats are subject to the prop going in and out of the water, especially with an outboard. If that happens it really does not matter what motor you have.

Sent from my SM-G900V using Cruisers Sailing Forum mobile app

[Atlantic42]

Issues:

1) Ventilation: Need Type 'X' or longer shaft to get propeller deep enough to prevent ventilation. BF9.9 available as 'type X' but BF25 only as shorter? 'L-type'.

2) Thrust: High thrust is better than standard in this use case. I believe Honda notates high thrust models as 'Power Thrust' as "BFP' vs standard 'BF' models. The BFP work better for displacement vessels and offer more thrust in reverse for enhanced maneuvering.

3) Weight: Less is more on a multi-hull. Not sure on the BFP models, but Standard Honda L-type 9.9h = 98lbs vs Standard Honda L-type 25hp= 160lbs.

4) Based on my experience with a similar style vessel (i.e. PDQ36 with high-thrust Yamaha 9.9's ), it seems high-thrust 9.9's would be more than adequate for a Seawind 1000.

[Mirage Gecko]

Thread drift alert!
Factor I just noticed your new Avatar have you left the family or a new baby?
Chris

[Boatguy30]

That's 6.8 knots with 2 9.9!?!??

My 11,000 lb 34' plywood cat does 6.5 knots on a single yamaha T8........ Was thinking of going to a 20 hp suzuki EFI as I reckon could have an easy cruise speed of 6.5 knots with maybe just a bit more fuel burn.

[rbrentp]

I do not have a Seawind. I have a 30ft Iroquois and a 35 ft Prout. The Iroquois has twin Yamaha 9.9 extra long high thrust. One will push the boat at 7kts. Two will make 11. Much shallower lighter boat but stated as a frame of reference. The PDQ 36 next door has the same outboards and gets about 3kts less with both and similar with one. That is closer. The Prout had two Yamaha 25s. One pushes at 6.5kts at 3200 rpms on smooth water with no wind. I state the RPMS because closer to cruise RPMs and the tendency to cavitation goes up fast. Have switched one to the Xlong shaft Honda 15. Eight inches more depth, higher output generator. Cavitation is gone. A single 25 at 3200 pushed the boat into a 25knt headwind in a shallow bay with four foot chop at about 4kts. The cavitation was terrible, hence the move to the 15. Talked to the manufacturers and the 15 hp Honda at cruise RPM is delivering more HP to the water than the Yamaha 25 at 3200. Add in the cavitation and the 15 is way more efficient, predictable, and lighter. You may notice I have spent some time wrestling with outboards and Cats.

[Factor]

Originally Posted by Mirage Gecko

Thread drift alert!
Factor I just noticed your new Avatar have you left the family or a new baby?
Chris

Same Family & new Baby. Seawind owns Corsair - or to be precise, Corsair Marine International builds Seawinds. But the Seawind company and management took over Corsair.

Dash on the way for an attempt to open up some new markets in the grey nomad sector! See how it goes.

[44'cruisingcat]

I would have bet on you getting a new 1160 sports! Is Dilligara sold?

[phalo]

Yes our 14 yo Seawind 1000 was changed to 2 x 20HP Honda long shaft high thrust props 10 years ago before my time so I have known nothing else. Fuel consumptions conforms with the book and there has always been adequate power in tidal flows up to 5k so it must have plenty of reserve power. She cruises at just over 6k in a light chop on 4000 revs and think it would do 7 flat out but haven't tried.

Tomfl what are sugar scoops?

[clownfishsydney]

Sugar scoops are another term for the transoms.