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Bombardier GT how many hp ?

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GtBoat

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I have a Johnson Bombardier GT from i dont know excatly a year cause i cannot read on engine precisely. Its around 2005-2007. This engine looks like standard 9.9hp but i think it has more power, i dont know how many, maybe you would know? Its a two stroke, benzine must be mixed with oild before come to engine.
 
A GT 10 was marketed and it was a same as the 15 hp I believe.-----Not sure if it was marketed in 2005 at least not in all markets.----------A picture of YOUR motor is what is needed here.
 
Exact year production of my engine is 2007, now i cannot make a picture cause i dont have mobile phone with camera. On engine there is written Johnson Bombardier and on back of engine theres no like always amount of HP, there is written GT.
Size of engine is like 9.9hp standard mayba a little bit bigger or no i dont know.
 
I see the GT decal on 2007 models !---But read post # 4--------------And there is no size difference between a 9.9 engine block and a 15 hp engine block !
 
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Yes thats why im interesting how many hp my engine got, theres no size difference. How many versions horse power were of GT bombardier 9.9 to max for example 16hp?
In Johnson factory what does mean GT ? Its like in cars more powerfull version of something ?
 
I had one, it was an earlier model than yours. My difference was it had the 15 hp carb and had a restrictor plate behind the carb. I pulled the plate out and got my 15 hp.
 
I tried to read on plate on engine how many KW it has but i cannot read, i tried with small torch and still cannot read, maybe i have to use UV torch?
I thought that this engine which i have has got around 12.5hp, i never supposed it has 15hp, i know that its stronger than normal 9.9hp, i see this when i sail with my not so big boat, it almost goes sideslip.
 
Is it possible that this engine has got 10.2HP ? I dont know excatly if i saw good, but i saw 7.5kw on plate on engine. What values are possible in this engine generally?
 
Find out if there is a proper boat shop in your area.------------Ask them if they have a " TEST PROPELLER " to run this motor.-------------A shop would then be able to say if it is 10 hp or more that 10 hp.-----A test propeller does not even resemble the propeller on the motor now !
 
Ive opened case of my engine and i found somethig like this:
"Engine has been modified by bombardier and its derated to a 10hp" What does it mean, im not expert in english so i dont know whats mean derated?
 
In my area theres not propeller test and even if it would be i wouldnt do that, i posted the picture of the same enigne like mine here in post 14 and i wrote what is written on sign on engine:
"Engine has been modified by bombardier and its derated to a 10hp"
Its not necessary for me to test engine like car how many horse power it has. I need this only to sometimes maybe repairing engine.
https://www.finn.no/boat/motor/ad.html?finnkode=57698523
This is my engine like in this page, everywhere on norwegian pages selling engines there is 15hp but on engine plate there is 7.5KW, it means 10.2hp thats why i dont know where is truth.
 
How to understand what is written under case of engine:
"Engine has been modified by bombardier and its derated to a 10hp"
On nameplate of engine theres is 7.5KW so it means engine is around 10.2HP, i dont think so it only has 10.2hp beacause my friend had johnson 9.9hp in almost the same size boat like mine and 9.9hp is much slower than mine engine.
On this norwegian auction you can see that theres written 10.2/15hk, hk means in norwegian horse power. I understand that normally engine is 10.2hp but bomardier modified it to 15hp? Am i right?
My engine is excatly the same like this :
https://www.finn.no/boat/motor/ad.html?finnkode=57698523
 
ok here we go.
your engine was made as a 15hp......BUT it was de-rated by factory to be around 10hp.

so any parts from the normal 15hp will b fine....

if you want more power then just take off the carburettor and where the gasket goes there "might" be a small plate with a smaller hole than back of carburettor.
if yes the take plate away and put carb back on and it is now normal 15hp.

at the moment have 10hp of power..
 
What is the sense to derate engine power to the lower power, i always thought that it is sense to make more power like in cars chiptuning, why Bombardier derated power to 10hp from 15hp? I dont get it.
 
ok I shall explain why.
when you insure a boat and engine , sometimes the boat might only be allowed 10hp maximum on transom !!!
this way you can have this size engine that is 10hp max at say 5,000 rpm but with good power upto 5,000 rpm .
if you have a boat that can have 15 hp then you buy it as 15hp and can run at maybe 6,000 rpm.

it is cheaper to inure 10hp than 15hp....and some lakes only allow 10hp.

mercury used to sell a 4hp , 5hp and 6hp outboard engine, all the same motor but different carburettor and jets etc.
to make the 4 into 6hp was bigger carb and then swing bigger propeller.

mercury make 50 and 60hp that is same motor now, and Honda 50hp is same engine Honda 60hp, 2 minutes to change for
the extra 10hp. just simple job,

so it makes sense to make more horse power range from 1 engine.

ford escort 1600 L and ford escort 1600 GT...same engine, big difference in power .... 1600L much cheaper to insure.
 
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Ok now i understand, this year i will not do this, but i want in next season i want to increase power of my engine to 15hp, my boat is not big so i think it will make it more faster, what shall i do to increase power? Only carburetor modification?
 
look behind carburettor first, sometimes it is just a thin plate to remove. sometimes bigger carburettor.
sometimes bigger jets in carburettor.
need number from carburettor to see if it is same size a 15hp model.

this is where you need to know what motor model number you have.

need to find number on the sticker try harder take pics and zoom in from all angles
 
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Thank you for your explanation, this is difficult for me to read information from plate, i tried with good light and with torch and i dont good see what is written there, possibly its 2003 or 2005, maybe i need UV torch?
This engine i have bought in Norway, there you can sail boat without any permission big engines, for example my friend in Norway sailed boat with 50hp Johnson and he had no any license, so its strange for me that Bombardier derated power to 10hp.
If i increase power do you think the fuel consumption will be biger ?
 
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