Is this big enough for a kicker?

seabird89

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My uncle gave me a 6hp Johnson Outboard that needs some work, is this big enough to use as a kicker for a 20ft boat with a Cuddy Cabin and a 140hp 2 stroke?
 

Sea Rider

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Will depend on the type of boating you like doing, on flat non windy water cond could push ok, on windy choppy water cond definetely not, but a prop mqaximization could do wonders, needd to tach that OB at full throttle and check max wot rpm, probably on the lugging side of the wot range which is bad for a kicker.

Happy Boating
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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6hp will be fine 90%-95% of the time the 5%-10% of the time you may need a tad bit more power. most of the time you can get by with about 3hp. a 2hp motor will move a 37' sail boat in fairly calm water at just under 3mph, last time I checked, that was fast enough for trolling.
 

seabird89

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Actually I should have stated my primary use will be to limp back home if my main engine fails. The boat will be used in salt water, but I don't plan on going out in rough seas.
 

JimS123

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Actually I should have stated my primary use will be to limp back home if my main engine fails. The boat will be used in salt water, but I don't plan on going out in rough seas.
That's what I figured, and that's why I suggested what I did. Sure, a 3 HP would work on a calm day, but when you have a problem its never calm......LOL.
 

Scott Danforth

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I went 4 miles against current and wind in a 17' bass boat with a 3hp electric trolling motor. You have the motor, try it out. You will be surprised
 

Sea Rider

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If that combo would be mine and already counting with a portable OB to use as a kicker, would install an induction tach, go for a wot spin as usually loaded, check achieved max wot revs, compare them to factory specs and dial a prop that revs around max wot revs for that OB. Maximizing a less prop pitch will rise rpm and push much better a heavier combo at better displacement speed as opposed to a standard factory delivered prop for recreational purposes. The way to go, check available props for that OB.

Happy Boating
 

seabird89

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May 9, 2016
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Scott, I agree with you, I was only asking because I have to get the motor running, buy a mounting bracket and mount it (closed transom), and figure out how I am going to get fuel to it. I just wanted to know if it was worth it before I went through all of that work.

Thanks everyone for the suggestions.
 

tomhath

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Dec 5, 2007
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Scott, I agree with you, I was only asking because I have to get the motor running, buy a mounting bracket and mount it (closed transom), and figure out how I am going to get fuel to it. I just wanted to know if it was worth it before I went through all of that work.

Thanks everyone for the suggestions.

You'll need the mount and fuel lines no matter what motor you end up with. The 6hp Johnson is a good motor so you shouldn't have any trouble selling it if you feel it isn't enough. Think about how you would start it too, you might want an electric start motor if it's hard to reach when in the water.
 

ondarvr

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You will want a long or XL shaft for a boat that size, but if you plan to put a kicker on it you will need a mount and fuel lines anyway, so you could put the 6 on there just to get an idea of what it will do.
 

seabird89

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That's a good point on the shaft length. How long does it need to be? I mean does the prop need to be as low as my main engine, or do I just measure the water line and make sure it is like a foot lower than that?
 

Sea Rider

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Install OB on transom sitting at 90 deg, go full grip, if prop aerates badly you need to install a mount out transom or go for a long shaft OB.

Happy Boating
 

ondarvr

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The lower the prop the better it will perform, but it doesn't need to be as low as the main. When you get into larger waves the kicker needs to be deep enough so the prop doesn't come out of the water. Also with a long shaft you can keep the powerhead higher so it doesn't get dunked in those same conditions.
 

seabird89

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OK, I have to buy a bracket either way because I have a closed transom (Seadrive). Any suggestions for a bracket that won't break the bank? I am trailering about 40 miles each way.
 

JimS123

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OK, I have to buy a bracket either way because I have a closed transom (Seadrive). Any suggestions for a bracket that won't break the bank? I am trailering about 40 miles each way.
I had brackets in the 1960's and ended up taking them all off. Hard to engage and bounced all over on the highway.

When I bought my current rig (in 1984) the typical bracket cost about 50 bucks. I ended up paying $125 for an OMC top-of-the line unit with a gas cylinder. It's still on the boat after 32 years and I've never dismounted the motor. Its been on there for 1250+ running hours plus I can't imagine how many highway miles.

Buy the strongest and most expensive model you can find. "Breaking the bank" truly means unsatisfctory for the job or needing to be replaced for a better one...
 
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