Can I put a 28 hp Johnson on my 14' Aluminum Sea King?

Seasons Recreational

Seasons Recreational

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HI all, I have a 2004 Johnson 9.9 hp 4 stroke slated to go on my 14' Seaking. I have the opportunity to purchase a 1987 Johnson 28 hp Johnson 2 stroke with controls and all, complete. Tempting.

The 9.9 weighs about 84-93 lbs, while the 28 weighs about 130-170 lbs.

Which is the better motor, and should I avoid such a heavy one as the 28 hp?
 
jimmbo

jimmbo

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I would keep the 4 stroke, as an Anchor.
The 28 would not weigh 170 lbs, I doubt it would even weigh 130. It would about the same as the 35hp below, which was about 122 lbs. It was a 20" model
We had 2 14 ft Mirrocrafts, one with a 25, the other had a 35. They were rated for 35hp though
mirrocraft2a.jpg
 
aspeck

aspeck

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You say the 28 has controls ... so it is not a tiller. That begs the question on how your 14' is set up ... is it an easy resto to put a console and controls in it? That will take up room ... and there isn't a lot of room in a 14'. I would imagine you 14' would "handle" a 28hp, but what is the rating of it? My guess is it is rated for anywhere from 20-35hp.
 
Seasons Recreational

Seasons Recreational

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aspeck said:
You say the 28 has controls ... so it is not a tiller. That begs the question on how your 14' is set up ... is it an easy resto to put a console and controls in it? That will take up room ... and there isn't a lot of room in a 14'. I would imagine you 14' would "handle" a 28hp, but what is the rating of it? My guess is it is rated for anywhere from 20-35hp.
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Thanks aspeck,

Yes, it's a controls boat. Just worried that the weight would sink the back too much into the water, but I'll be up front and just have kiddos, batteries and tank at the back. Based on my calculations, it's rated for a 15 hp, but not sure if I calculated properly.
 

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Seasons Recreational

Seasons Recreational

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jimmbo said:
I would keep the 4 stroke, as an Anchor.
The 28 would not weigh 170 lbs, I doubt it would even weigh 130. It would about the same as the 35hp below, which was about 122 lbs. It was a 20" model
We had 2 14 ft Mirrocrafts, one with a 25, the other had a 35. They were rated for 35hp though
View attachment 406693
Click to expand...
Thanks jimmbo,

This is what I'm afraid of! Doing all of this work then being underpowered! If I do the calculation on the Sea King, it's rated for 15 hp max. but I think that would still be underpowered. What's the reality of putting an outboard on her that's beyond the power rating? I see people with overpowered boats all the time...Will I get boarded by the authorities and cited?

Also, does it make a difference that I'll be sitting up front and not at the back as would be the case with a tiller setup?
 

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BWR1953

BWR1953

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About 15 years ago, I had a 14' Sea Nymph boat that had side helm. It was rated for 35HP, but I had a 25HP Mercury on there. It worked fine and yours would likely be about the same. I figure that my Sea Nymph got up to about 25MPH.

 
A

airshot

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If you knowingly overpowered your boat and get involved in an accident, even not your fault, you could be sued for neglegence. Risky move no matter what....your insurance may not cover your overpowered boat.
 
jimmbo

jimmbo

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Where I am(Canada), there are NO Laws that make it Illegal to put more Hp on a Boat than the plate recommends. There might be some Issues regarding Insurance, but I always told them the Boat had more HP(sometimes 50hp more) on it than the Plate, and I was never refused by an underwriter.
 
Scott Danforth

Scott Danforth

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are the seats and transom going back into the boat first? referencing the pics from post #4. the seats add structure to the boat

if the boat is only rated for 15hp. then look for a 15hp motor
 
Texasmark

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jimmbo said:
I would keep the 4 stroke, as an Anchor.
The 28 would not weigh 170 lbs, I doubt it would even weigh 130. It would about the same as the 35hp below, which was about 122 lbs. It was a 20" model
We had 2 14 ft Mirrocrafts, one with a 25, the other had a 35. They were rated for 35hp though
View attachment 406693
Click to expand...
I had a 14' Mirrocraft like these but with console steering from the rear seat and a 30 HP Merc Mark 30 pushing it. Ran out real nice and that hull was smooth riding on 10-20k acre lakes. Fishing buddy had a 14' Alumacraft with the same type of steering setup and a 33 HP Johnson. Ran out real nice.
 
aspeck

aspeck

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If you go with the 28, you might want to move the batteries to the front of the boat.
 
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cyclops222

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Weight of the driver enters into overpowering little boats. 275 to 350 pounder needs A LOT of power !!
 
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gbrowne63

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we have a 14 ft springbok [now princecraft [that has had 10 to 40hp on the back of it. the boat was rated for 40hp in 1959. the last motor was a 25hp johnson with a 10x15 pitch prop and it did 32mph with one person on board. my bet is you can put up to 40 or 50hp on the back and it won,t sink.
 
Texasmark

Texasmark

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Seasons Recreational said:
Thanks jimmbo,

This is what I'm afraid of! Doing all of this work then being underpowered! If I do the calculation on the Sea King, it's rated for 15 hp max. but I think that would still be underpowered. What's the reality of putting an outboard on her that's beyond the power rating? I see people with overpowered boats all the time...Will I get boarded by the authorities and cited?

Also, does it make a difference that I'll be sitting up front and not at the back as would be the case with a tiller setup?
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"Also, does it make a difference that I'll be sitting up front and not at the back as would be the case with a tiller setup?"

Of course. Thousands of posts and conversations about tiller driven boats where the owner asks about the load in the aft section only to get replies of "move xxxx forward".

If you have a splash well, that goes a long way in relieving one's worries. I have had both with and without and every "without" I ever owned I wished it were a "with".

Another thought in worrying about water over the transom is how you drive your boat. If you are at WOT at the tiller and "chop" the throttle, expect a big transom wake coming in as the boat settles in the water. if you slow the reduction in speed that "wave" is mitigated by how much you slow down in your decent.
 
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