Motor size?

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HogWild
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Motor size?

Post by HogWild »

I'm looking to build my first boat (look at Questions before buying section). Maybe this should go there :doh: . But seems like 9.9 or 15hps are the prevailing motors when I look at pics and specs of boats 13 to 16 ft. Embarrassed to ask :oops: , but why is this? Availablity, price, what? :doh:
Wood Chips and Sawdust is as close to Potpourri as I get...
Get Me outta here. That Gator's bigger than the boat...
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cape man
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Re: Motor size?

Post by cape man »

Jacques designs are light and meant to go with less horsepower than many other boats. The HP recommendations are based on the type of hull and weight. Some give a range, but most of the study plans just give the max HP which is based on his liability for that size boat and configuration. You are wanting something in that size range that will go with an 8hp correct? There was some confusion in one of your other posts where someone gave you an extra hp or two and started recommending a GF16.

Are you building around your existing motor, and if so, do you need it to plane? Look at the Fast Skiff 14. I built two boats now around the motor, so I fully appreciate what you are trying to do. Just realize there may be a compromise in performance if you build a boat big enough for what you want, and only have 8 horses to push her.
The world always seems brighter when you've just made something that wasn't there before - Neil Gaiman

HogWild
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Re: Motor size?

Post by HogWild »

No I don't have motor ( stolen couple yrs ago). Came across a good buy on 8hp. Just wondering why 9.9 & 15hps. Mine don't have to plane, just get out of it's own way. After meeting Jeff in person we kinda think the D15 ( Indian River Skiff) may fit my bill. But still open to ideas. I did think about the FS14. :-D Thanks Cape Man
Wood Chips and Sawdust is as close to Potpourri as I get...
Get Me outta here. That Gator's bigger than the boat...
Sometimes I'm Fast, Other Times I'm Half Fast.....

Capt UB
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Re: Motor size?

Post by Capt UB »

Hello,

I'm building the FS14 with a Tohatsu 9.8 4 stroke (87 lbs.), I am told that a long shaft is what is needed. My ob is short shaft, but may just work. Check with some of the builders of the boat you want to build and see what shaft they are using.

The threads in this forum are a great source of info and help. Don't just read the posts about your boat, they all have tricks or something that could help you out!

Good luck,
Bob.

TomW1
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Re: Motor size?

Post by TomW1 »

Capt UB No problem with you short shaft. Just measure down from your mounting plate to the ventilation plate and cut the transom to that height. There is also a How To up above on how to do it.

Tom
Restored Mirror Dinghy, Bought OD18 built by CL, Westlawn School of Yacht Design courses. LT US Navy 1970-1978

Capt UB
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Re: Motor size?

Post by Capt UB »

Thanks Tom, I did read the how to. I did measure like you said and got 18 1/2" (2017 Tohatsu 9.8 4 stroke), the plans show 19 5/8" on the transom. I'm going to wait and see how it works, then maybe try one of the JP's I have. That's so far off at this time.....

Thank you, Bob.

deuce_454
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Re: Motor size?

Post by deuce_454 »

the FS14 will work just fine with 1 10 horse, (i modified mine a little by lowering the height of the stringers and adding a flat floor, and moved the 2. nd frame back to give more floor space) but its still a FS14 .. and 20 horse is not too much, also running a 20 horse at half-1/3 throttle is a lot less noise than a 9,9 at full throttle....

id say get the biggest engine that fits your needs, - weight, price .. (within reason....)

Capt UB
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Re: Motor size?

Post by Capt UB »

I'm running a 2017 Tohatsu 9.8 4 stroke short shaft (18.5") with electric start and charging, 87 lbs. I will probably use a JP with 3 plus setback and maybe 2 up. I'm going to wait and see what she does with the ob on the transom.

I'm old, if I go fast I get lost..... ;)

TomW1
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Re: Motor size?

Post by TomW1 »

Capt UB wrote: Sun Oct 22, 2017 8:23 am I'm old, if I go fast I get lost..... ;)
I'll second that :lol: :lol: :lol:

Tom
Restored Mirror Dinghy, Bought OD18 built by CL, Westlawn School of Yacht Design courses. LT US Navy 1970-1978

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