73 johnson 135hp carb question

[spacerust]

i recently bought a 73 johnson 135hp from an older gentleman that works on outboards. he told me that he had changed the carbs to be a 90hp and that on this particular model the difference in hp is basically just the carbs. now i just want to clarify this. i asked him if later that i wanted to up the hp do i just need to change the carbs. he replied yes. so i'm confused. when i buy parts for this motor or have question i always put that it is a 135hp. so far no problems but is this correct? are the carbs interchangeable as he says? could i up the hp by buying different carbs? what would i need to do should i pursue this?

 

[CharlieB]

Re: 73 johnson 135hp carb question

Manufacturers have made whole series of engines, varying HP by the bore size and jetting of the carbs.

The only way to tell for certain is to look up your model and serial # to see what was original equipment on your motor.

It is entirely possible that smaller carbs have been installed to limit HP. One advantage is better fuel economy and a longer engine lifetime.

New carbs may be quite $$$$, if the boat works well with what you have, you may want to keep it that way while you patiently wait, hoping to find a good used set of original carbs.