Need Some Carb Help

[Circle Hooked]

I need to know what this part is called, it's off my 15 hp Yamaha you can see it's all cracked, the rebuild kits I have seen don't seem to have this.


The part resides in here.


Thanks for the help.

[wingtime]

HArd to tell by the pic but I'd almost say that is an accelerator pump diaphragm.  Does the rod get pushed in by the throttle?

[Capt. Bob]

Well,
I'm no piston head but I love a good mystery so.....

I'll guess (I always do).
It looks like a diaphragm used on a CV carb. The 2 CV (upside down in photo) hints at this. I didn't know they used CV type carbs on outboards and I don't know if this is really one but.....

Looky here- #10 maybe
http://www.yamahaoutboardmotorpart.com/ ... _-_2002%29

My experience with CV carbs are from motorcycles and the diaphragm controls a needle that moves the slide in relation to the change in pressure that occurs when the actual throttle moves the butterfly valve. Your photo doesn't look like the carbs I'm used to in the motorcycle world but I'm thinking this is the part you may be looking for.....

Good luck.

EDIT: Wing's pump idea makes more sense. Looks like it somehow is pushed by the throttle but is hard to make out.
Bet that link is what you're looking for.

EDIT (yet again): When you follow the exploded view, it appears to work some sort of check valve and probably allows extra fuel to enter the intake stream. I'd say Wing's got it.

[wingtime]

I was thinking about the CV idea too.

Is this it?:  http://www.boats.net/parts/detail/yamaha/Y-66M-14368-01-00.html

[Capt. Bob]

Part #s match.

[fitz73222]

Accelerator pump

[Circle Hooked]

HArd to tell by the pic but I'd almost say that is an accelerator pump diaphragm.  Does the rod get pushed in by the throttle?

Yes it does,  I had to always run with the choke slightly engaged to keep it from stalling, hopefully this is the problem.

Thanks for the help everyone