40-45-50hp carb fit a 35 hp motor?

Athon08

Cadet
Joined
Apr 30, 2009
Messages
23
will a 40-50hp johnson carb fit 35hp johnson outboard and run right and increase hp to the carb size?????

if so, what all would i have to do?...can't be as easy as just bolting on a bigger carb can it?
 

freddyray21

Commander
Joined
Jun 10, 2006
Messages
2,460
Re: 40-45-50hp carb fit a 35 hp motor?

you will not increase hp by changing the carb. there is more to it than that
 

Athon08

Cadet
Joined
Apr 30, 2009
Messages
23
Re: 40-45-50hp carb fit a 35 hp motor?

yeah, i was thinking there was...just seen alot of article about changing 25s to 35s.
if that were the case, why spend the money on a motor with 10-20 more HP when you can save about 2 grand and spend 250 on a new carb
 

tmcalavy

Rear Admiral
Joined
Aug 29, 2001
Messages
4,005
Re: 40-45-50hp carb fit a 35 hp motor?

Would help to know the year motor/outboard you are talking about. As freddy says...different carb doesn't necessarily mean more hp. I have a carb from a 58 Johnson 40 hp on a 56 E-rude 30 hp...they fit/swap out correctly because differences are very minor.
 

F_R

Supreme Mariner
Joined
Jul 7, 2006
Messages
28,226
Re: 40-45-50hp carb fit a 35 hp motor?

A '58 Johnson would be 35hp, not 40. So you only went up one notch. The 40hp came out in 1960.
Anyhoo, back to the subject,
1956 30hp has a 2 7/8" bore, 35.7 cubic inches.
1957-59 35hp has 3 1/16" bore, 40.5 cubic inches
1960-up 40hp has 3 5/16" bore, 43.9 cubic inches.
That blows the just-swap-the-carburetor theory.
 

CATransplant

Admiral
Joined
Feb 26, 2005
Messages
6,319
Re: 40-45-50hp carb fit a 35 hp motor?


Unless you can tell us which 35 hp outboard you're talking about, we won't be able to help you. What's the model number or year?

35 hp outboards were made in several different groups of years by Evinrude and Johnson. They are vastly different in design.

As for swapping carbs, that alone won't do you much good. On the later model engines it'll probably make your outboard run worse, not better.

If your carburetor is bad, get another one for your model. If you're looking for more performance, sell your outboard and buy a bigger one. That's my advice.
 
Joined
Jul 30, 2008
Messages
172
Re: 40-45-50hp carb fit a 35 hp motor?

Likely won't help, and you'd have to get the jetting right even if the intake manifold opening would be enlarged to match the exit diameter of the carb throat.

A 1974-1995 20, 25, 30 is an intake-restricted 35. You can increase the hp by bolting on any 1974-1989 35 carb. A friend used a 1975 75 hp carb on his 25 and got a big hp boost, but had to increase the high speed jet size considerably. However, the 35 carb has a bigger throat than the 75 one.




will a 40-50hp johnson carb fit 35hp johnson outboard and run right and increase hp to the carb size?????

if so, what all would i have to do?...can't be as easy as just bolting on a bigger carb can it?
 
Joined
Jul 30, 2008
Messages
172
Re: 40-45-50hp carb fit a 35 hp motor?

Likely won't help, and you'd have to get the jetting right even if the intake manifold opening would be enlarged to match the exit diameter of the carb throat.

A 1974-1995 20, 25, 30 is an intake-restricted 35. You can increase the hp by bolting on any 1974-1989 35 carb. A friend used a 1975 75 hp carb on his 1980-something 25 and got a big speed boost, but had to increase the high speed jet size considerably. However, the 35 carb has a bigger throat than the 75 carb.




will a 40-50hp johnson carb fit 35hp johnson outboard and run right and increase hp to the carb size?????

if so, what all would i have to do?...can't be as easy as just bolting on a bigger carb can it?
 

Athon08

Cadet
Joined
Apr 30, 2009
Messages
23
Re: 40-45-50hp carb fit a 35 hp motor?

not sure if the exact year...it is a 80's model though....where do you find the model number to determine the year
 
Top