Upgrade from 4HP to 6HP

[bobmccullough]

Hi,<br /><br />I believe that the Johnston/Suzuki outboards are the same engines, also that the Mercury/Mariner/Nissan/Tohatsu outboards form another group of identical engines, apart from badging. <br /><br />The mechanical specifications 4, 5 & 6HP outboard motors detailed in the brochures produced by each of these groups appears to show little difference between construction of each of the horse power ratings. I assume that the main difference is in the fuel supply. If this is the case it seems that within each group it would be possible to uprate or down-rate an engine between 4, 5 or 6HP by substituting fuel supply systems or by changing jets.<br /><br />My questions are, Is it possible to do this?, Are there any drawbacks? and Is it economically feasible?<br /><br />The difference in price between a 4 and a 6HP seems large just for a different fuel system as each would cost approximately the same to manufacture.<br /><br />Bob

 

[JB]

Re: Upgrade from 4HP to 6HP

You have to be specific on this question, Bob.<br /><br />In general it would cost more to upgrade the power rating on identical blocks than it would to buy the larger engine, but there are exceptions.

 

[TOHATSU GURU]

Re: Upgrade from 4HP to 6HP

The Tohatsu/Nissan/Mercury engine is the same except for the carburetor. The jets are fixed and cannot be replaced, but switching the carb from one to another does change the deliverable hp. In theory it also is against the law.

 

[deejaycee_2000]

Re: Upgrade from 4HP to 6HP

Johnson and Suzuki are definately not the same, Evenrude and Johnson are the same, If suzuki was anything like Johnson it would have made my life so much easyer.

 

[phatmanmike]

Re: Upgrade from 4HP to 6HP

Originally posted by theDeeJayCee:<br /> Johnson and Suzuki are definately not the same, Evenrude and Johnson are the same, If suzuki was anything like Johnson it would have made my life so much easyer.

hes talking about the newer suzuki/johnson 4 strokes. yes they are the same.

 

[deejaycee_2000]

Re: Upgrade from 4HP to 6HP

ok that makes sense, I'm not much updated on any 4-stroke outboards so you tought me something I didn't know .. thanx