30hp Carb- VS--35hp Carb..?

[frustratedboater]

Greetings all,
I wanted to run a technical question by you all. I have a 35 Bigtwin (57') that I'm putting together. I have scrapped a nice 30hp and would like to use the carburetor off that. It looks to be in nicer shape and much cleaner than the 35hp carb.

My question is, are there much differences in these two carbs? The number on the body of both is #30432. Also, does/did evinrude use the same carb on the 30 and the 35? If I use the 30carb on the 35 block, will there be a performance issue? The only subtle differences are a glass-bowl fuel filter on the 30, and a fuel nipple that eccepts the fuel hose directly on the 35.

I'M STUMPED!!
-----------------------------------
~frustratedboater~

 

[F_R]

Re: 30hp Carb- VS--35hp Carb..?

I don't have the specs, but if there is a difference it will be the size of the venturi. If you don't know, the venturi is the diameter of the big airflow hole through the center bore. Compare the two and you will have your answer. I'd say it is an almost sure bet the 35 is bigger. That would be because the 35 is a larger displacement engine, breathing more air.

 

[frustratedboater]

Re: 30hp Carb- VS--35hp Carb..?

Thanks, the one carb is attached to the air silencer, but will take a look. The only thing that I am in question over are the model numbers being the same....strange. The venturi will tell the story. thank you..

~Frustrated....~

 

[wavrider]

Re: 30hp Carb- VS--35hp Carb..?

Most likely you are lokng at the casting numbers of the bowl or upper half of the carb.

The difference as stated earlier will be the orfice/jet size.

If you are able to soak the carb and remove the jets (takes special tool) you can sure insert the 35hp jet into the 30hp carb which would make it a 35.

Performance issues? Probaly not a whole lot as it would act like a 30 hp instead of a 35, probaly onle a few 100's of difference in the two jets if you mic them out.

There are rebuild kits available from this site and the rebuild is fairly easy, Reccomend just rebuild it and have the correct one.

I ran 90 hp carbs on my 115 until I finally figured out what they were and replaced the jets with the correct size. good luck

 

[F_R]

Re: 30hp Carb- VS--35hp Carb..?

Not. He's talking about 1956-57. Adjustable HS needles.

 

[wavrider]

Re: 30hp Carb- VS--35hp Carb..?

Not. He's talking about 1956-57. Adjustable HS needles.

stand corrected, did not read the year just the heading of the post. thanks F.R.

 

[frustratedboater]

Re: 30hp Carb- VS--35hp Carb..?

Actually, I forgot about the jet sizing, which would make sence. Ill just use the carb off the 35, but will need some major rebuilding, but It's do-able. Thanks for the help, clairifications, and suggestions...