Motor suggestion for 14ft aluminium

zul

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Aug 24, 2015
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Bringing a 14 footer back to life. No leaks. Needs a new transom.

Will an 8 hp motor get this on plane with a light load?
Will 8 hp get on plane if the boat is loaded or max load?

I'll get a power prop on there.

I found good looking Evinrude 8 hp for $500. If it passes the compression test, seems like a really good deal? The guy claims it's barely been used.

This boat would be used mostly on lake. But there is a river that everyone says you 'need' 20-30hp to get upstream. Hard to find an outboard around here in the 20-30hp range. What might a used motor in this range set me back $$ ? And, can a normal person lift and mount a 20hp motor with a rolling motor stand?
 

F_R

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There is a world of differences in boats. The 14' Alumacraft jon boat that I used to have would barely plane with some 5hp motors, but not others. So I guess you would call that borderline. On the other hand, the 14' semi-V that I have needs 18hp or more. It flies with 35hp.

River?? Again, depends. How fast does it flow? A planing boat will probably make headway, a dog, probably not.

Normal person? Sure, I lifted a bazillion 20hp motors back in "The Day", but now that I'm in my 80's, a 10hp can be a strain.
 

racerone

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Well the old 18 / 20 HP motors were about 85 lbs.-------Lighter than some modern motors.----Another key factor on motor choice is " can you do your own work ? "
 

zul

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This 14-foot boat is an old V-hull. Will the 8 hp get it to plane with two people and no gear? And, if it doesn't, how bad does it suck to ride around off plane? Ergh.

Can't even find a 20 hp used around here. I can work on 2-strokes and have a good mech if the carbs need help. Do most motors in that range use pull cords? At what hp do things switch over to electric starting?
 

F_R

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I'm guessing 8hp would be borderline to plane the boat.

A 20hp motor is not hard to pull. Generally speaking, 9.5hp would be considered the smallest with electric starting.
 

JimS123

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Our 14' Sea Nymph (deep freeboard, wide beam, about 175 # dry, tiller steer) will plane with a 9.5 2-stroke and 2 adults and 2 teenagers aboard. Its rated for 25 HP, but gets squirrely above 18 HP.

When I had a 25 Yami 2-stroke on her I could lift the motor from a stand onto the transom, but at 55 years old i did appreciate help with it.
 

flyingscott

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I would skip the 9.5 hp motor because they will have exhaust issues that can be expensive to fix. They are also not the most powerful motors. An 18/20 hp is a good choice and can be found with electric start. Those motors will not charge the batter however. A good choice would be a 9.9/15 motor can be found with electric start and will charge the battery. The 9.9 is a much more powerful motor than the 8 or 9.5 motors. The 9.5 will be fairly equal to the 8 hp.
 

roscoe

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what hp is the boat rated for?

How much does it weigh? floor? livewell? pedestal seats?

If a generic 14' aluminum utility boat, then I would look for a 1984 or newer evinrude, johnson, or Mercury 15 hp.

I just picked up a nice clean Merc 15, 1990, electric start, for $600.
 

Sea Rider

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For a under powered 8 HP-OB to power nicely a large boat will need to prop it right to run at max wot rpm range factory stated. Just don't exaggerate over loading the combo. One less prop pitch from current one will do the trick as factory delivered current prop is usually medium pitched.

To play safe going per a less pitch will need to buy and install an induction tach to check max wot revs achieved on flat calm water cond while boating lightly to medium light loaded. A combo that does not plane achieves extra hull drag along poor speed which translates into a slow boaring outing..

Happy Boating
 

zul

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Aug 24, 2015
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This boat is stripped down, bare bones. Prob 150-180 lbs. I've found an older 15 hp and 18 hp evinrude, 1968. The motor looks real clean in photos.

Difference between short shaft and long shaft? I assume the long shaft has a better chance to plane? And obviously the short shaft does better in the shallows... ??

I will be sure to compression test before buying ... For the compression test, 130 is great, just over 100 is tired but worth buying ?? So long as the results are within 10 of each other?
 

racerone

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NO-----A short shaft and long shaft motor both should have the same amount of motor sticking below the boat !!-----A short shaft fits a boat with a 15" high transom.----A long shaft fits a boat with a 20" high transom.----Same amount of motor below the boat.
 

zul

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Ah, yes. Just read up on some of that. 15" makes this one a short shaft.

Is there a specific gas can and line to be used? I have the regular 6 gal red cans (for gas storage) but I don't think that is the proper setup.
I do have a squeeze bulb and gas line, but again, probably a specific connection to the can is necessary.
 

roscoe

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You need an outboard motor fuel tank.
One that is rated for marine use.

Most motors you buy will likely come with a fuel tank.

The seller will need a fuel tank so you can test run the motor before purchase.

If seller wants to keep the tank, just look at what he has for a tank and fuel line.

The connectors on the motor are different for every motor brand.
And in many cases, the connector on each end of the fuel line is different.
(the tank connector is different from the motor connector)
 
Joined
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Short shaft motors tend to be harder to come by but they are out there. An 8hp would be fine on your boat in general, but getting on plane is another thing. Whether or not it gets on plane is a question that depends on too many variables, such as the weight of the boat, how big of a guy you are, gear, etc. The bigger question is do you need to get on plane? Maybe you need it in the river but are you planning on fishing all over the place, or just putting from spot to spot? I have a 12' Starcraft from the 60's that I use with either a 3hp or a 5.5hp. Neither gets it up on plane but I'm fine with that. Little boats are tippy at speed.
 

jimmbo

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If a 14 ft Vee hull were to plane with an 8hp, I would be amazed. Our 14ft Mirrocrafts had 25 and 35 hp engines.
 

Twitches

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Jan 30, 2018
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9.9 is bare minimum. You will be bored / frustrated with anything less. I have a 14th alumacraft that runs pretty heavy. I have an old 2 stroke 15 on it and still want more power. I had a tohatsu 8 on it (great motor) with a 450 pound load and it would plane, but barely. My father in law hopped in and no go..
I upped to a 9.9 and it was a little better but still felt slow.

Unless your waters are power limited, get the biggest motor you can find and afford.

And stick with older 2 strokes, especially if you don't mind tinkering. They are relatively simple to work on and resources for how to do things and diagnose issues are readily available. You should be able to find a nice late 80's 15hp in good shape for 500-700 running and ready to go. Do not buy a motor without running it first, shifting the gears, ensure water out tell tale etc. Don't be in a hurry. Anyone trying to sell it without demonstrating it is hiding something.
Would disagree about little boats being tippy at speed. I run 19mph on my 14ft and at that speed it is very stable and controllable.
 

tramsdell

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Jul 25, 2018
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Op, go with a 15 at minimum. Once you put a buddy in there or gear or even just a cooler and factor in weather. You will be borderline dangerous with anything less than that.
 
G

Guest

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Our 14' Sea Nymph (deep freeboard, wide beam, about 175 # dry, tiller steer) will plane with a 9.5 2-stroke and 2 adults and 2 teenagers aboard. Its rated for 25 HP, but gets squirrely above 18 HP.

When I had a 25 Yami 2-stroke on her I could lift the motor from a stand onto the transom, but at 55 years old i did appreciate help with it.

I have the same boat, with a 25 Evinrude, Boysen reeds and a ballistic propeller. As Jim says, she can get a little squirrely if you have no weight in the bow, but a cooler up forward, and an additional 6 gallon tank (or passenger) and she calms down quite nicely and she flies.

As for a planing motor, My neighbor had this same Sea Nymph model, with a 9.5 Johnson, and I remeber it plaining out with 3 guys aboard.
 
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