Horsepower

[fishfighter]

Is it possible to do some work to a 1997 2 cylinder 40hp yamaha to get more power out of it without boring it out, like changing the carbs and stuff, don't want to get to deep into the motor but i would like to go a little faster

[Ray]

Yes, most 40 hp motors are the same as 50 hp and 60 hp.
The manufacturers just fix em up to run at what ever hp you wanna buy.
I had a 3 cyl. 25 hp. Suzuki that was good for duck hunting, but a dog
when gator hunting. Had it fixed up to a 35 hp for about $100.
Same with my old 3 cyl. 40 hp Merc. Cost was a lot cheaper to get it to
60 hp than it was to buy a 60 hp engine. It was around $150.

You won't have to change carbs, but you will prolly need to change the
jets and reeds. I don't have the ability to do it, but I got it done at
the Suzuki shop for the Zuki and at Gene's Marine for the Merc.
I also had to add a lil pitch to the props.

[fishfighter]

thanks ray for the info and quick response

[CajunChristian]

If that's the 2 cylinder, single carb model, it is what it is. That was a "stand alone" block, it was not used for any other size outboards. Just like the old Mercury 2 cylinder 40hp Sea Pro, just like the old Tohatsu M40C, 2 cylinder single carb..
D

[fishfighter]

Originally Posted by CajunChristian

If that's the 2 cylinder, single carb model, it is what it is. That was a "stand alone" block, it was not used for any other size outboards. Just like the old Mercury 2 cylinder 40hp Sea Pro, just like the old Tohatsu M40C, 2 cylinder single carb..
D

it is a double carb

[Ray]

Originally Posted by CajunChristian

If that's the 2 cylinder, single carb model, it is what it is. That was a "stand alone" block, it was not used for any other size outboards. Just like the old Mercury 2 cylinder 40hp Sea Pro, just like the old Tohatsu M40C, 2 cylinder single carb..
D

I did not know that about the 2 cyl., single carb'ed engines.
Mine were 3 cyl. and were used in different hp models.

[CajunChristian]

Originally Posted by Ray

I did not know that about the 2 cyl., single carb'ed engines.
Mine were 3 cyl. and were used in different hp models.

Yea, Ray, if yours was 1991 or older it was a 51 cubic incher, if it was post 1991 it was a 59 cube. Merc also made a ton of the old "Sea Pro" models 2 cylinder single carb. Tohatsu built one, their M40C, a 30 cubic incher. That is the motor we raced in "Sport C", the "C" being 30 cubic inch class.

A 2 cylinder 2 carb might have some possibilities.
D