01ps Posted May 24, 2010 Share Posted May 24, 2010 I have an 82 XS400 I had my bike going today and it was running fine. I slowly got worse through the day until is started "chugging" and losing power at higher rpm. I took the carbs apart again thinking there was some new dirt, but went a step further than before. I pushed out the needle tube and it was filthy and plugged. Cleaned it up, cleaned the holes, etc. Put the carb back together and now it won't start! Took the float bowls off and checked the floats, noticed they were binding a bit so I cleaned out the pivots good. The float bowl lwvwl does not seem to be enough but the tangs are already bent some. Also, if I leave the bike to sit, fuel runs out of it like crazy in the filter side of the carb. I disabled the vaccum petcock, but fuel should not pour out when it is sitting, shold it? Question, when I first too kthe carbs apart, there was a rubber plug in one of the jets, the small one. Why would it be plugged, and is it supposed to be? Link to comment Share on other sites More sharing options...
Speedshop Posted May 24, 2010 Share Posted May 24, 2010 Those rubber bungs are supposed to be there to stop fuel entering at that point. Link to comment Share on other sites More sharing options...
HoughMade Posted May 24, 2010 Share Posted May 24, 2010 If fuel is pouring out, your floats are not working correctly. When i went through my carbs I set the floats to what the manual said- 32mm and fuel poured out. Some years are supposed to be 26mm, some 32mm, but 26mm seems to be the safer bet, though I have mine around 29mm because the manual said 32mm. It could also be caused by dirt on the float needle seat. And yes, those plugs should be there. It forces the enrichener circuit (some people call it a choke, it is not) which is used on start up to draw fuel through the main jet. There is a passage between the two- check that to make sure it is clean. If you main jet was clogged, that passage and the entire enrichener circuit could be as well. Good luck! Link to comment Share on other sites More sharing options...
sporkcow Posted June 13, 2010 Share Posted June 13, 2010 If fuel is pouring out, your floats are not working correctly. When i went through my carbs I set the floats to what the manual said- 32mm and fuel poured out. Some years are supposed to be 26mm, some 32mm, but 26mm seems to be the safer bet, though I have mine around 29mm because the manual said 32mm. I have been dealing with the same issue on my '81 XS 400. The right carb leaks fuel out of the air box, especially when I have it sitting on the kickstand (as opposed to the center stand). I have adjusted the floats twice now, and it hasn't gotten much better. The last time I set both floats to about 29mm, but the result was the same. I think I may be measuring the distance in the wrong place. With the carb upside down, I move the float so it just touches the needle but does not depress it, and am measuring from the seating surface on the carb body to the bottom of the float. Is this correct? Link to comment Share on other sites More sharing options...
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