Do i have a safe boat motor combo?

P

poolicker

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• Aug 9, 2006

• #1

I have a 12ft princecraft like aluminum boat with a 25 hp johnson slung on the back hooked up to some cable steering. Is this to much hp for the boat? Annndd....ummmmm. How fast will it go?:=

 

D

danpemby

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• Aug 9, 2006

• #2

Re: Do i have a safe boat motor combo?

Look at the previous tread post by jtexas
http://forums.iboats.com/bbBoard.cgi?a=viewthread;fid=1;gtid=1142676

 

P

poolicker

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• Aug 9, 2006

• #3

Re: Do i have a safe boat motor combo?

I did the calculation and apparently i should only have 15 hp, is this reason to get a differat motor?

 

P

poolicker

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• Aug 9, 2006

• #4

Re: Do i have a safe boat motor combo?

Alsoo can anyone balpark the top speed, my son always says '' daddy how fast will dat go?'' and i honestly cant say.

 

D

danpemby

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• Aug 9, 2006

• #5

Re: Do i have a safe boat motor combo?

If you have the information you can go here: http://www.rbbi.com/folders/prop/propcalc.htm.
or
http://www.go-fast.com/boat_speed_predictions.htm

It really depends on a lot of factors

What is your transom width?

 

P

poolicker

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• Aug 9, 2006

• #6

Re: Do i have a safe boat motor combo?

The prop is a 15 pitch three blade genaric thingmi, the transom is 4 feet wide, and the boat wieghs about 200-250 pounds....just guessing.

 

C

cobra 3.0

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• Aug 9, 2006

• #7

Re: Do i have a safe boat motor combo?

About 30+ mph

 

Chief101

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• Aug 9, 2006

• #8

Re: Do i have a safe boat motor combo?

My guess on speed is somewhat over 20 mph depending on age of engine (early 80's and before were hp rated diferent than today engines), elevation (at higher elevation you will be slower), and condition ( bad prop and or hull condition).
I had a similar setup with a '73 20hp engine. The prop was all dinged up and the hull was somewhat banged up so all I could get out of it was 22 mph with 300# of folks and gear. With only myself and a headwind I think I could have easily tipped it over. Depending on how far forward you are seated you might be just fine horsepowerwise. Chief Chief .)

 

deejaycee_2000

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• Aug 10, 2006

• #9

Re: Do i have a safe boat motor combo?

Yes you have a safe boat, enjoy it ....

 

jtexas

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• Aug 10, 2006

• #10

Re: Do i have a safe boat motor combo?

note that those USCG rules are...kind of like stop signs...more general guidelines than actual rules 8)

there's exceptions for boatbuilders who can demonstrate a boat's ability to handle more hp.

plus which, you might be rounding your measurements...if it's actually 12.5 feet long/4.5 feet wide, you're almost in the 25hp ballpark.

 

Bob_VT

Moderator & Unofficial iBoats Historian

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• Aug 10, 2006

• #11

Re: Do i have a safe boat motor combo?

Some boat companies rate their boats with two sets of numbers for horsepower. One set (lower) is for tiller steering and the higher is for conventional steering (higher). Either way a 25 will make a small boat scoot along.

 

bjcsc

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• Aug 10, 2006

• #12

Re: Do i have a safe boat motor combo?

I can't believe you guys are actually seriously reponding to obviously non-serious, non-sequitur, adolescent posts by a "member" named "poo licker". Geez!...

 

Texasmark

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• Aug 10, 2006

• #13

Re: Do i have a safe boat motor combo?

Yeah, and before you listen to deejaysee you need to look around here for the pic of him about 15' above the surface of the water, in ocean waves, probably off Cape Horn, in his inflateable, telling us that when he comes down it's a soft landing......Hmmmmm :/

Makes me think of mountain climbers who hang, suspended from the underside of cliffs, on one spike he drove into the rock. Too much thrill for me. Grin

Mark

 

jtexas

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• Aug 10, 2006

• #14

Re: Do i have a safe boat motor combo?

adolescent? par for the course...this is a forum about boats after all 8)

 

P

poolicker

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• Aug 10, 2006

• #15

Re: Do i have a safe boat motor combo?

Bjcsc, fyi i am 48 years young, and about the name ''poolicker'' i was repainting my sailboat named wind licker from the previous owner and when i whent back to gather some supplies my son had written poo over the wind lettering, resulting in '' poolicker'', so i just left it the way it was, and the name stuck

 

D

danpemby

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• Aug 10, 2006

• #16

Re: Do i have a safe boat motor combo?

All I can say to that is I am glad some of the names Mrs. Danpemby have called me never stuck!

 

Zaairman

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Jun 16, 2006

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39

• Aug 10, 2006

• #17

Re: Do i have a safe boat motor combo?

Not that I would ever do this or anything...but a CANOE will scoot nicely with a 9.8 Merc, and two 150lb riders....:devil:

 

F

ferrariman

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• Aug 10, 2006

• #18

Re: Do i have a safe boat motor combo?

I had a 25hp johnson comercial on a 14ft aluminum and it went like a bat out of hell, little under proped though, 6200 at WOT, didnt stay there for long. But with the cable steer you say you have you should'nt have and issues with being blown over. I had to put sandbags in the bow of mine to keep her down. Take her for a test spin and and realy some results to us.

 

Reel Poor

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• Aug 10, 2006

• #19

Re: Do i have a safe boat motor combo?

Somebody has been using like that, take it out for a spin and see what she'll do and how it feels.

"How fast will it go?'..........I don't think your gonna get wind burn.

 

deejaycee_2000

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• Aug 11, 2006

• #20

Re: Do i have a safe boat motor combo?

Texasmark said:

Yeah, and before you listen to deejaysee you need to look around here for the pic of him about 15' above the surface of the water, in ocean waves, probably off Cape Horn, in his inflateable, telling us that when he comes down it's a soft landing......Hmmmmm :/

Makes me think of mountain climbers who hang, suspended from the underside of cliffs, on one spike he drove into the rock. Too much thrill for me. Grin

Mark

Click to expand...

hahahaha it is a soft landing ... like I said the aerodynamica of the boat makes it come down softer .... i'll try and get pics to show you ... the front of the boat between the two pontoons have a spoiler wing like nose to balance out the wind with the weight at the back to bring it down as even as possible .....