Replace carburetor on 2005 Yamaha 9.9 4-stroke

[boscoe99]

There appear to be 3 different carbs just for the 2005 F model; cannot imagine why though; also it appears the only difference between a G9 and a G8 carb is the choke mechanism; if you contact Yamaha as advised by Boscoe the first thing they will ask you for is the engine serial number....

There is only one carburetor for each of the various F or T models offered by Yamaha in 2005.

There is more to a model than if it begins with the letter F. Or the letter T.

Today there are multiple F200 models. They can be completely different from each other. Some are inline versions, some are V models, some are mechanically con*****ed and some are electronically con*****ed. If one simply goes to the parts catalog for their specific model, and chooses only the parts listed in the catalog for their model, they can't go wrong.

Using the wrong Yamaha parts book would be as wrong as using a Mercury parts book. Just use the right parts book.

[99yam40]

when you put together a motor from different models it becomes hard to figure out which parts book to use

[zenoahphobic]

I don't have the engine or serial number close at hand. I'm pretty sure either the F model carb or T model carb will physically fit. The issue is whether or not the standard leg or high-thrust leg requires a particular carb for best operation. The serial number will be tied to an engine with a standard leg. I'm not using the standard leg.

Reliance on numbers instead of knowledge and experience is a continuing trend. One cannot be "bold" much anymore. I increasingly am also finding it very difficult to explain to people in the business when I wish to buy something that I don't have the serial no because I don't have the damn thing that has the serial number!

[raptorman]

That is precisely why I want to know the difference between the carbs and their effect on performance with different gear ratio and diameter/pitch of prop. Shouldn't be this hard.

[rodbolt17]

its not hard
the F and T motors were somewhat different.

use the carb that the engine wiring harness and intake passage was designed for.

that's what happens when units get cobbled.

[boscoe99]

That is precisely why I want to know the difference between the carbs and their effect on performance with different gear ratio and diameter/pitch of prop. Shouldn't be this hard.

I am not a fuel systems engineer. Wish that I was but alas I am not.

You are looking for something that will be known by only a handfull of people at Yamaha in Japan. If even they knew the answer I would not be able to understand them given I don't speak Jap.

Now if we knew the whole story, the answer might be there is no appreciable benefit using one carburetor versus a different one. I retired from a company full of engineers and you could not believe all of the stuff they did not agree upon.

And by the way, the smaller motors are made by a company in France for Yamaha. This might be a French thing. Or maybe the carby maker, Mikuni, had some different carbys they needed to get rid of.

It is your choice. Six of one or half dozen of the other.

[zenoahphobic]

A trip to France and Japan sounds nice.
I can see a mini series documentary out of this.
Pity that would cost many times a new motor.