Carb issue

Lemonysword

XS400 Enthusiast
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Almost five years ago my wife tipped the bike over and it began leaking gas out the left air intake. I'm ashamed to admit I haven't messed with it once since my initial attempt to rectify it. See my previous thread on my attempted restoration of the bike here.

Today I have removed and disassembled the carbs. I believe I have found the source of my issue. On the left side (the leaky side), the float sits significantly higher, and when I push up on it, the needle valve does not move. However, the issue persists and remains isolated to the left side even when I swap the floats and needles from side to side.

I think it's possible the mounts for the float may be damaged or bent but there is nothing immediately noticeable. Again, this issue is isolated to the left side regardless of which float is installed on the left side. The photo attached shows the heights of the floats.

Any ideas?
 

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When you say “swap the floats and needles from side to side”, are you also switching the float seats too? If not, possibly it’s not just a stuck needle. It might also be that it is not seating properly, or the seat is clogged…etc, etc
 
No, I was just moving the float and the needle itself. However I did wind up solving this. After almost five years of letting it sit again...

Anyways, the hole for the pin that mounts the float is off center on the left carb. The little tab on the float to keep it from rotating within a certain limit was set at about the same for both floats, close enough I couldn't tell them apart. I'm guessing when the bike tipped, it jostled the float just enough to bend that tab enough to keep the float from moving properly. I bent it back into shape and experimented a bit, just put the bike back together and ran it a few minutes (started on the first kick) and it hasn't leaked a drop.

So now I get to go back through and clean this filthy thing up, and finish all the small stuff I meant to do years ago like new chain, sprockets, oil change in the forks, and clean the rust off all the chrome
 
Interesting. Who would have thought! It certainly doesn’t take much to bend the tabs, and that float level makes such a difference to so many circuits in the carbs. That’s what’s great about these forums, information that not available in service manuals. I too am replacing my sprockets, my chain. In fact I’m replacing so much I sometimes think “I should just part this old bike out”. But the nice thing about them, is they were made to be owner serviced. Unlike newer technolgy.
 
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