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  #1  
Old 10-03-2009, 01:19 PM
hil hil is offline
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clueless re outboard motor size

this totally clueless want-to-just-go-fish newbie is getting advice that is all over the place, and my web travels brought me here, where the knowledge base is obviously far over my head, but here goes...

given: 14' inflatable, calm waters (lake or harbor), 2-4 people, not concerned about 'speed' as much as just getting around safely and being able to maneuver back to port in windy weather... boat is 'rated' for up to 40Hp motor and 2000+ payload... may occasionally have 4 people on board, plus gear...

all I'm trying to do is figure out what is a reasonable size or range for motor... I'm assuming 4-stroke for various reasons, including new environmental regulations... weight is a factor since will have to 'handle' it each outing... I'm seeing 'advice' anywhere from "5 Hp will do it" to "at least 25-30HP"... these are vastly different... can anyone give me simple lay-understandable picture on what is needed (or what I can expect from different size motors on this lightweight high-riding craft...???

any help will be much appreciated
hil
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  #2  
Old 10-03-2009, 02:03 PM
Submarine Tom Submarine Tom is offline
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Are you in a position to borrow an outboard?

I'd start with what ever you can get between 10 and 40Hp.

I tried an 8, 10, 15 and a 25 on my house boat before deciding on the

Merc 25Hp Bigfoot. My gut feeling is 20-25Hp. Have you Googled that

particular boat to see what others are running on it and what they're doing

with their's?

Tom
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  #3  
Old 10-03-2009, 04:38 PM
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PAR PAR is offline
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With a 5 HP outboard, you'll move, but very slowly and unable to get up on plane (probably), which is what the boat is intended to do. You'll likely need a minimum of 15 HP just to get on plane with a light load, 20 HP with a full load (maybe), so you want to error on the size that will still get you up to planning speeds, but not suck you're wallet dry with fuel bills. So, 20 to 25 HP will be the ticket and a new one will cost about 2 to 3K depending on how good a deal you can swing and brand. Without knowing what the make, model and year is of your boat, little more then these generalities can be offered.
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  #4  
Old 10-04-2009, 11:27 AM
hil hil is offline
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some additional input:

primary anticipated use is not speed... lakes and protected harbor areas... casual fishing or just 'browsing'...

boat is new Sea Eagle SR14, inflatable/collapsible w/floorboard panels, max. motor rating 40hp, max load rating 2000lbs+...

with not more than 2 on board (most likely use), I'm projecting probable weight is: 200 pounds for the boat (hull and floor panels), maybe 100-125 or so for motor (using average of what I've seen for between 10-25hp, for preliminary figure), 150-200 pounds misc. gear, 300-325 pounds passengers... so total only 800 pound range... adding 2 more people (occasional only) would be around 1100-1200 pound load

research so far suggests quality differential between motor manufacturers in this size range is not that great... in California only 4-stroke is logical... on line Tohatsu manual start prices are ranging from $1729 for 10hp to $2475 for 20hp (15hp and 18hp between this)...

the weight above 20hp takes a big jump and I'm not sure I want to wrestle more than the 114# on and off the boat each outing (15, 18 and 20hp Tohatsu's are all same weight)... the whole idea was to have portability and minimal storage, so motor would not be mounted except at the launch location each time out...

a separate question will be whether the primary motor will double for trolling... it sounds like the newer 4-strokes in motors this size are relatively quiet and controllable at slow speeds, and if true I could pass on a separate trolling motor (reducing both cost and pounds)... am I off base on this, or is a separate troller a necessity?

I'm open to any thoughts...
thanks again
hil
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  #5  
Old 10-04-2009, 11:36 AM
hil hil is offline
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tom...
to answer your questions...
no I'm not able to borrow for 'testing' purposes...
and web searches (many hours' worth) have not been that helpful, with results all over the place (and generally don't sound very 'reasoned' or explained in enough detail to make me think the advice is sound)...
discussion threads here are first ones that seem to be more thoughtful and based on experience as well as science, so hope to learn more...
again, thanks,
hil
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  #6  
Old 10-04-2009, 02:29 PM
Submarine Tom Submarine Tom is offline
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hil,

Hmmmmmm...

To plane or not to plane may be your question then.

I'm going to say 20 Hp.

Are you buying new or used?

Are you able to trade up if you find 20 too small?

Where did you get the boat from?

No history?
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  #7  
Old 10-04-2009, 11:42 PM
hil hil is offline
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tom...

I'm going to say 20 Hp.

...thanks for input...

Are you buying new or used?

...new...

Are you able to trade up if you find 20 too small?


...i suppose it's always possible but i'm sure it would be at a substantial loss....

Where did you get the boat from?

...Costco, best deal around, $1850 including package of extras and delivery...

No history?

...not sure I understand the question...


thanks again
hil
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  #8  
Old 10-05-2009, 11:39 AM
Submarine Tom Submarine Tom is offline
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If it was used I thought it may have had some history, like what motor was on it before. It's a shame you can't find anyone else who's bought one.
Nothing on the Internet 'eh? What about the manufacturer? You may have to be clever/persistant/invasive to get any info out of them. What about the sales rep who sold the boat to Costco.
Great deal but not so great if you have to buy three motors in order to solve your problem. I think I'd try and swing a deal with the emgine sales guy that if you're not happy you can trade up for a fixed amount. A condition of sale, if you will.
Good luck,
Tom
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  #9  
Old 10-05-2009, 01:33 PM
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Fanie Fanie is offline
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Hil,

Personally I would consider a larger motor. The small new motor may just make it, a few years down the line it may be too small. One size up also means you won't run the poor motor flat out all the time. I would fit a motor that can comfortably propel the boat and the fishing gear. You may want to add a trolling motor and batteries later on, get a bigger tackle box as will your fishing companion. It adds up fairly quick.

Inflatables are fairly light to launch. If your's have a problem you may look into why it is so.
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  #10  
Old 10-09-2009, 08:28 AM
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mwatts mwatts is offline
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You might not want speed al the time, but speed will definately be nice if you're out on the water and the weather suddenly turns around and you want to get to shelter fast.

Considering the fact you want the motor to be portable, I suggest getting the biggest engine you can honestly call portable, and that will be in the 20 - 25 HP range. If you get anything bigger, you'll find yourself shopping for a trailer pretty soon.
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  #11  
Old 10-09-2009, 08:34 AM
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Yes well, that is always the problem. Things are too big on land and too small on the water.
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  #12  
Old 10-09-2009, 11:24 AM
hil hil is offline
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thanks to all for the input...
after much angst, settled on a 20hp 4-stroke Tohatsu, and am pretty confident this will suit my needs...
after I get a chance to break in and spend some time on the water, I'll check in and let you know how it worked out, just for future reference...
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  #13  
Old 10-09-2009, 11:26 AM
hil hil is offline
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oh, and Fanie... you were talking abou boats, right??? :-)
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  #14  
Old 10-09-2009, 11:44 PM
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Its also worth remembering that you must check the prop is right for the boat engine combination ...check your WOT rpm once its run in and if its at the top end of the rev range increase the prop pitch knowing it will drop 400 rpm for each 2 inch pitch increase ...the supplied props often have too small a pitch ....
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  #15  
Old 01-12-2010, 12:36 AM
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sandhammaren05 sandhammaren05 is offline
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The Evinrude E-Tecs (all are 2 stroke) pass the EU environmental rules, so no problem. These will provide far better acceleration that the 4 strokes and are lighter. A better choice, for me, would be an older (1976-1993) 2 stroke Evinrude/Johnson 35 or Mercury 35. They're light (about 110 lb) and very powerful. No 4 stroke can run with them. Older outboards are generally not eliminated by environmental rules in Europe, where the environmental rules are excessively stiff.




Quote:
Originally Posted by hil View Post
this totally clueless want-to-just-go-fish newbie is getting advice that is all over the place, and my web travels brought me here, where the knowledge base is obviously far over my head, but here goes...

given: 14' inflatable, calm waters (lake or harbor), 2-4 people, not concerned about 'speed' as much as just getting around safely and being able to maneuver back to port in windy weather... boat is 'rated' for up to 40Hp motor and 2000+ payload... may occasionally have 4 people on board, plus gear...

all I'm trying to do is figure out what is a reasonable size or range for motor... I'm assuming 4-stroke for various reasons, including new environmental regulations... weight is a factor since will have to 'handle' it each outing... I'm seeing 'advice' anywhere from "5 Hp will do it" to "at least 25-30HP"... these are vastly different... can anyone give me simple lay-understandable picture on what is needed (or what I can expect from different size motors on this lightweight high-riding craft...???

any help will be much appreciated
hil
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