Single Carb Fuel leak

[digitalsam]

Ok, I fixed the fuel petcock leak! now when the petcock is off, the fuel does not leak. Woo hoo! But, when the fuel is on, the second carb from the left drips fuel (A drop per second, roughly) Not a big amount, but it drips right onto a hot engine... I think that is probably bad.

Any ideas? why is the one carb leaking? and more importantly, how do I fix it?

[jwoell]

You have an issue with your float valve not fully shutting off the fuel flow once the bowl has filled. This causes it to overflow and leak out the back of the carb and possibly the front and into the engine as well (see if your oil smells like gas cause this can be a bad thing if it's thinned out).

Are you running in line fuel filters? There is most likely something gunking up the needle and seat and causing it to not fully close. Either that or possibly that the needle and seat are worn, I'm not sure if you replaced them recently or not. The other thing is that if the floats drop too low they can kinda jam up and stick because of that. There is a tang on the float itself that you can bend to adjust how far it drops down. I can't seem to find the link to that right this second. I'm sure one of the guru's will be by and know off the top of their head. You can sometimes fix this by tapping on the carb lightly to free it up.

Oh and I think the o-ring that seals the seat into the carb body can get worn out and leak too, so that's maybe something to check out as well.

[prometheus578]

What he said.


Once you get the carbs off, flip them over and remove the float bowls. Hook up a fuel source and see what's goin' on in there.

[digitalsam]

Ok, thanks. The rubber boots that hold the carbs onto the engine are pretty old. Any suggestions on how I can remove them?

[TopCatGr58]

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I think you're pretty good with computers , try following
This Link/thread to an ONLINE MANUALS source, follow username/pswrd instructions.

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http://www.yamaha-motor.com/sport/parts/home.aspx
Just click go to parts section, select Motorcycles, Year, Model from the drop downs, and then peruse the info!!

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T.C.