Yamaha 426 leaking carb

Hi everyone

got a leaking carb but can't work out where it's coming from, sure it's the drain screw in the bowl. But it's tight and it only does it when it's bin running for a while, and doesn't leak much just odd drop.


How come mine doesn't have a leak jet ?!


It could be the seal has gone out around the lip of your float bowl. My wifes Triumph started leaking around the carb and couldn't figure out where, until we cleaned it so good that you could see fuel slightly leaking from top of the bowl. Pull the bowl off and inspect the seal to see if it flat or smashed, let alone cracked in any way. Just trying to help.

Thanks for the reply, I thought that at the start so iv tried new bowl seal. And cleaned it all, it's coming from lower than that, sure it's the drain screw? Should there be a o ring seal on it?

And do you know why my bowl doesn't have a leak jet ?


BTW, if you ever look to replace a worn drain screw from the bowl, it is not listed on the WR parts diagram.  Look at the YZ diagram instead.

Thanks for the help guys, iv replaced the bowl seal it's not that I don't think. Yea it is only the odd drop but on the road after a while that adds up lol

It's just strange how it only does it when it's bin running a while, can leave the fuel switched on and it won't leak. Only when it's hot

Also stupid question but is the gold jet in the bowl the overflow? It seems blocked as I can't blow down it


It's probably leaking from the fuel inlet

Pull it and replace the orings

Your bike has no leak jet on purpose

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