Please help experienced advice needed

[Schlacky]

Hello all, Im Alex and I have just taken the plunge to make my sailing dreams closer to reality. I have just purchased a Waller 6.7 meter trailer Catamaran
(Mike Waller Yacht Design.com.au) but I need some advice on selecting a motor. Lack of experience has left me in a bit of an indecision No if s or buts it has to be a 4 stroke extra long leg preferably with a tiller that folds all the way back to the cover so is not in the cockpit when in the up position. Having looked at all major brands they all offer compromise and all dealers are less than helpfull. I am resigning to 1 of 2 choices being a Mercury 9.9 bigfoot or a 9.9 tohatsu exl leg. My big question arises when I consider the gear ratios Mercury 2.42:1 and Tohatsu 2.08:1 about 17% difference. I know they are the same motor. I just dont have the experience with either monos or multis to decide if I need the extra thrust or wether the tohatsu will do the jub just fine without laboring or cavitation my concern is I want enough thrust to be confident in a seaway one dealer said just whack a 15 hp prop on it ( the tohatsu) but I am not that confident about such advice as there has to be a mechanical trade off some where ( probably in the main crank on a 2 meter swell making my way to port on the other hand will the merc be too slow? any experienced advice please

[rikhall]

Alex. Congrats on your new yacht. Good on ya!

Do some web searching and see if there is a Waller 6.7 web users group. Or even a Waller users web group. Reading and corresponding with owners of the same yacht would be really helpful.

I am not sure how many of those I would see across the pond and up top of the world here.

Good luck in your search.

Rik

[Flybyknight]

9.9 hp is way too much hp for a 22 foot boat!
I have a 25' full deep keel boat weighing 4,000 lbs. and down sized my engine from an 8 hp Honda to a 6 hp Nissan extra long shaft and it is entirely satisfactory with it's 2.15::1 gear ratio. I think that anything less will be like starting a car in 3rd gear. Nissan's 6" pitch is perfect for a sailboat and gives more than adequate thrust.
The reason for the change was weight.
Weight in the stern is slow.
Rethink your hp requirements, after all you do not want a tug boat.

Dick

[GulfTriton]

I agree 9.9hp is too much for a 22' boat. I also use a 6hp Nissan (Exact Same as Tohatsu) but my boat is 28' long with a full keel and weighs in around 8,000 lbs.

[dnf777]

How much does the Waller weigh?
I saw one for sale on amazon that had a 9.9 on it.
That looks like a pretty substantial boat, even if only 21 feet.

[GulfTriton]

If built to spec they should weigh about 2,500 lbs.

[dnf777]

well, I'm probably the farthest thing from an experienced sailor on here...but have lots of experience with motoring.....and my standard reply when someone asked if "its too much motor" was always........."that's why they have throttles!"

;-)

[zedboy]

The rule of thumb that's quoted is 3-4 hp per ton displacement.

Hanging a lot of extra weight at the stern is not a good idea on an already light boat.

[Schlacky]

Help I cant post any replies it just keeps blanking when I hit preview

[Schlacky]

yeah so that one posts