Will a 6hp Johnson push my 14' sea nymph?

[bigbass87]

It's a 1976 sea nymph 14' by 5' wide deep V. The motor I'm lookin at is a 1972 Johnson 6hp that runs good for $200. My boat has plywood floors installed with a casting deck, battery, trolling motor, and tackle. Sometimes my girlfriend goes with me. I weigh about 160lbs and she weighs 130lbs. So will this motor be big enough and what mph will I get out of it with my setup?

 

[JoLin]

Re: Will a 6hp Johnson push my 14' sea nymph?

IMO, 6 hp is enough to move that boat. Essentially, your max speed over water will be the equivalent of 'hull speed' in a displacement hull. Works like this- since your motor isn't powerful enough to get you on plane (putting most of the boat above the water), you reach a point at which the bow wave you're 'pushing' becomes large enough to negate the power of your motor. In a 14' boat, I'll guess that your max speed with 6 hp will be about 5 mph.

My .02

 

[12vMan]

Re: Will a 6hp Johnson push my 14' sea nymph?

I would hold out for at least a 10hp. 5hp will 'move' the boat, sure, but getting it on plane and being able to get back to shore if there's trouble brewin is another story.

 

[ziggy]

Re: Will a 6hp Johnson push my 14' sea nymph?

when i was a kid in the 60's. we had a 14' wood larsen, 3.6hp ob. also a 16' aluminim sears fishing boat w/ 6hp wards sea king on it. sure they'd move the boat, better than oars even. but agree w/ jolin. it will be at displacement speed. nothing wrong with that if ya don't have anything but time and don't go out when the weather might kick up and ya need some speed to out run the storm... agreed with 12vman too on the 10hp ob. the 16' aluminum woulnd't plane with a 6hp, but i borrowed the neighbors 10hp johnson and she planed good with that, with one aboard. all my stated observations were with one on board w/o any gear... extra weight on a small boat has a large effect as to how they handle and what they're capable of....

 

[JimS123]

Re: Will a 6hp Johnson push my 14' sea nymph?

First of all you don't have a deep V. Yours is a flat bottom semi-V. All that extra weight will be a hinderance for sure.

If yours is the "std" model with a 57" beam a 9.9 would probably be acceptable. The boat is rated for a 15 HP max.

If yours is the "rugged duty" R series with a 62" beam, the max rating is 25 HP and would do nicely with a 15-18 HP motor.

These are just guesses since I don't know the weight of the add-ons. Surely a 6 HP would not be adequate for either model, since it would not plane the boat.

 

[bigbass87]

Re: Will a 6hp Johnson push my 14' sea nymph?

First of all you don't have a deep V. Yours is a flat bottom semi-V. All that extra weight will be a hinderance for sure.

If yours is the "std" model with a 57" beam a 9.9 would probably be acceptable. The boat is rated for a 15 HP max.

If yours is the "rugged duty" R series with a 62" beam, the max rating is 25 HP and would do nicely with a 15-18 HP motor.

These are just guesses since I don't know the weight of the add-ons. Surely a 6 HP would not be adequate for either model, since it would not plane the boat.

My boat is a 1976 14R Big Water

 

[Pony]

Re: Will a 6hp Johnson push my 14' sea nymph?

I would assume then being the max hp is 25, then this boat is very similar to my Alumacraft. I have a 25hp on there now, but I have used an 18hp, a 9.9, and a 5hp on it in the past.....

The 5hp pushed the boat, but as stated above it was at displacement speed. It took FOREVER to get back to the dock. Not fun if it was windy.
The 9.9 was ok. Better than the 5hp to be sure, but it still wasn't going to get you anywhere fast. It was better than displacement speed.
The 18hp was good. In fact I would have no problem using the 18hp all the time except for the fact that I was only using it while my 25hp was getting a new water pump and waiting for parts.
The 25hp is awesome. It just absolutely flies.

I would look for something in the 15-20hp range. IMO

 

[2ndtry]

Re: Will a 6hp Johnson push my 14' sea nymph?

That 6hp will not get that boat up on plane, but will get you where you need to go, displacement "hull" speed for a boat your size is 5 mph. Thats the best you can hope for.

A 9.9 will get you on plane (perhaps the gf as well, not sure how much your casting deck weighs), and easily gets you 3X the speed.

 

[bigbass87]

Re: Will a 6hp Johnson push my 14' sea nymph?

Thanks for all the good posts guys.....Now on my hunt for a 15hp

 

[drrpm]

Re: Will a 6hp Johnson push my 14' sea nymph?

A rule of thumb for decent performance is to have at least 70% of rated power. So if its rated for 25 HP you would want at least 18 HP.
The 6 HP motor will move it and so will a set of oars, just not very quickly.

 

[JimS123]

Re: Will a 6hp Johnson push my 14' sea nymph?

My boat is a 1976 14R Big Water

So that's exactly the same as mine. The 9.5 was OK with 2 adults and 2 kids, but it was no speed deamon. The 25 was too big - never felt safe at speed. A 1974 18 HP 'Rude was what I considered optimum.