SPORT 13 with 9.9-HP

Optimizing the performance of Boston Whaler boats
Nsp
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SPORT 13 with 9.9-HP

Postby Nsp » Tue Nov 06, 2018 9:05 pm

Hello Whaler Community. I recently picked up a 1979 SPORT 13 in need of new wood seats and console. I intend on restoring it with help from my 13-year-old son. In New Jersey kids under 16-years-old with a boating safety certificate can operate a boat over 12-feet in length with an engine under 10-HP. A 13-footer with a 9.9-HP is going to be somewhat anemic.

Would a light rig without a console in a standard trim be best?

Or, would performance be better with the driver's weight more forward behind the Sport console?

I realize the Sport console will add weight. Any help will be greatly appreciated.

jimh
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Re: SPORT 13 with 9.9-HP

Postby jimh » Wed Nov 07, 2018 8:44 am

According to Boston Whaler, a 13-foot hull can reach plane with 9-HP. See

http://continuouswave.com/whaler/reference/13/

A 13-year-old will find boating more exciting if his boat can get on plane. On that basis, the total boat weight should be kept to a minimum. I suggest the initial set-up be with just the outboard engine and minimal extra weight. If the boat can get on plane without a struggle, then perhaps the added weight of the console, remote steering, remote controls, and more seating can be tolerated.

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Re: SPORT 13 with 9.9-HP

Postby jimh » Wed Nov 07, 2018 9:09 am

Does your 9.9-HP engine have electric start and electric power trim-tilt? Those features add weight and need a battery--more weight. Those added weights should also be considered in the decision to use tiller steering or remote steering.

Nsp
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Re: SPORT 13 with 9.9-HP

Postby Nsp » Wed Nov 07, 2018 10:05 am

jimh-- thank you for your reply.

I haven't picked up an outboard yet. but I, too. was thinking pull-start without trim. So you feel, keeping the weight down is more advantageous than having the weight forward. As you suggest, I am leaning towards a standard set-up. In NJ once the kids reach 16-years-old, they are no longer restricted to the 9.9-HP maximum.

Don SSDD
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Re: SPORT 13 with 9.9-HP

Postby Don SSDD » Wed Nov 07, 2018 5:31 pm

Maybe you can borrow a 9.9 and see how things go, assuming you don’t have one already. Kids need to learn on under-powered machines in my opinion so they can grow into the bigger power.
1986 Outrage 18 with 2001 Honda 130 HP
Former Owner 1991 Guardian 19 with 1994 Evinrude V4 140HP
Former owner 1987 Montauk with 1998 Mercury 90HP
Nova Scotia

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Dutchman
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Re: SPORT 13 with 9.9-HP

Postby Dutchman » Thu Nov 08, 2018 2:34 pm

Don SSDD wrote:Maybe you can borrow a 9.9 and see how things go, assuming you don’t have one already? Kids need to learn on underpowered machines in my opinion so they can grow into the bigger power.


To the OP: I [endorse] the statement above, especially if [your 13-year-old son] wants to go out unsupervised.

There must be somebody you know in the marina with a inflatable that has such [a 9.9-HP] engine.

Like you said and assumed: [performance] is all weight related with smaller boats.

Maybe a tiller extension could do the trick. Good luck with the restoration.
EJO
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Nsp
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Re: SPORT 13 with 9.9-HP

Postby Nsp » Thu Nov 08, 2018 2:57 pm

Thank you all for input, that's a good idea. I will try out a 9.9-HP and see how it goes.

jimh
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Re: SPORT 13 with 9.9-HP

Postby jimh » Thu Nov 08, 2018 6:17 pm

The need for a 9.9-HP comes from the limitation of the New Jersey law, not from anything else in particular. If the 13-year-old is going to be legally eligible to operate the boat alone, the engine must be not greater than 9.9-HP. Even if the OP borrows a 9.9-HP and tests, he won't have any options for higher horsepower, unless he abandons his initial desire to build a boat his 13-year-old can operate.

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Dutchman
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Re: SPORT 13 with 9.9-HP

Postby Dutchman » Fri Nov 09, 2018 9:47 am

Even if the OP borrows a 9.9-HP and tests, he won't have any options for higher horsepower, unless he abandons his initial desire to build a boat his 13-year-old can operate.

True Jim but the OP can then determine if that gives him a performance that is satisfactory.
EJO
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50th edition 2008 Montauk 150, w/60HP Mercury Bigfoot

MarkCz
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Re: SPORT 13 with 9.9-HP

Postby MarkCz » Fri Nov 09, 2018 1:22 pm

I had a SPORT 13 of that [c.1979] vintage for 30 years. The boat initially had a 25-HP two-stroke-power-cycle engine with electric start and side console cable steering. Good engine choice. I sold the 25-HP and bought a 9.9-HP two-stroke-power-cycle engine so I could operate on a local lake with 10-HP limit. I did not use [remote] steering but used tiller control. [Using tiller steering] was uncomfortable as the rear seat should have been moved further aft but would get on plane with me (250-lbs) and my two boys about 75-lbs each back then. It was underpowered. They raised the lake limit to 20-HP so I bought a 20-HP two-stroke-power-cycle engine, and that was a big improvement, but [the propeller] would still cavitate with four people in the boat. The old Johnson Evinrude outboards were available from 20 to 35-HP in the same size engine.

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Re: SPORT 13 with 9.9-HP

Postby jimh » Fri Nov 09, 2018 7:16 pm

My wife's aunt had a SPORT 13 with a 25-HP Evinrude. You could pull up a water skier--albeit a light water skier--with that rig.

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Re: SPORT 13 with 9.9-HP

Postby jimh » Sat Nov 10, 2018 8:42 am

Dutchman wrote:...the OP can then determine if that gives him a performance that is satisfactory.

The goal is to have a boat his young son can run. It is gonna go as fast as a 9.9 can push it.

jimh
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Re: SPORT 13 with 9.9-HP

Postby jimh » Sat Nov 10, 2018 8:47 am

MarkCz wrote:I had a SPORT 13 ...[Using tiller steering] was uncomfortable as the rear seat should have been moved further aft...


The problem you had was your boat was a SPORT. When Boston Whaler made the 13 STANDARD model--not intended for a console and remote steering--then Boston Whaler DID locate the rear seat farther aft to make tiller steering easier.

To change the location of a thwart seat on a 13-foot hull is not much of a task. If the boat under discussion ends up with tiller steering, then the thwart seat can be moved farther aft to create a better position for tiller steering.

jimh
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Re: SPORT 13 with 9.9-HP

Postby jimh » Sat Nov 10, 2018 8:55 am

Get a 9.9-HP with pull start for these reasons:

--without electric start the engine will be lighter, which will help maintain the best performance;

--without electric start the engine will be cheaper;

--without electric start the engine won't need a heavy starting battery on the boat;

--without electric start, your son will have to learn the proper starting procedure for the engine so he can start it with one or two pulls; if he has an electric start engine, he will just crank and crank until it starts. When you have a pull-start outboard, the operator will appreciate keeping the engine in good tune and using the proper starting procedures like applying fuel enrichment or spark advance, so that it starts on the first pull.

v12mac
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Re: SPORT 13 with 9.9-HP

Postby v12mac » Mon Nov 12, 2018 3:33 pm

I grew up on a SPORT 13 with a 7.5-HP engine, and the boat planed just fine.

I'm in the process of building a SUPER SPORT 13 with my son. We have the same rules here--less than 15-HP under 12 years old.

We picked up a 9.9-HP four-stroke BIGFOOT. I'll post performance results when the boat is set up.

MarkCz
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Re: SPORT 13 with 9.9-HP

Postby MarkCz » Mon Nov 12, 2018 7:51 pm

The 9.9 was easy to pull start and I don't think a 13 year old would have any problem starting it as long as the engine is in good shape. The 20 I had required way more strength.

dtmackey
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Re: SPORT 13 with 9.9-HP

Postby dtmackey » Mon Nov 12, 2018 10:03 pm

My vote would be for a Yamaha two-stroke 9.9-HP, since they can be easily bumped to a 15-HP, and from the outside no one can tell. I have one that this was done and also a Yamaha 25 two-stroke with 15 decals. Not to mention, the two-stroke has better torque down low--in case there are several people in the boat you can still get on plane.

The young-operator laws of Massachusetts make no sense whatsoever. No operation under-12 without and adult. At 12 you can take a boating course, and once passed you can run any boat without a restriction on horsepower. So a 1,500-HP is legal, which I find insane. I never agreed with this, and I let my son run the Avon with a 5-HP; he learned lots and was ready to move up.

My feeling has always been kids must be able to run a boat and work their way up, so I think the HP restriction is the best way to allow them to learn and then move into something bigger.

D-