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More ?'s about '83 xs400


Chicken
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Hi all! So here is yet another question about the bike I just aquired. I'm noticing some fuel leaking around the rubber parts around the carbs. I think these may be referred to as the carb intake boots. Is this a serious issue? The clamps that are closer to the engine seem tight. It's the parts that are closer to the rear of the bike that seem to be leaking a bit. Any suggestions?

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Hi all! So here is yet another question about the bike I just aquired. I'm noticing some fuel leaking around the rubber parts around the carbs. I think these may be referred to as the carb intake boots. Is this a serious issue? The clamps that are closer to the engine seem tight. It's the parts that are closer to the rear of the bike that seem to be leaking a bit. Any suggestions?

float levels wrong and flooding the carb

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What Drewpy said, had the same issue with my bike. As for whether tis serious - when trying to kickstart my bike it backfired through the carbs (hell if I know how or why, as my coils seem dead), and caught 'em on fire, flame was small and with no fire extinguisher anywhere nearby and two fairly expensive and fairly new cars within 5ft from the bike I had no choice but choke the flame down by covering the carb intake ports and thus cutting off the oxygen supply. I got lucky, you may not be as much - pull the carbs off, check the float level. Also check the fuel tank selector valve as it should shut off fuel when left in the "on" setting with the engine not running - tis a vacuum diaphragm inside taht runs off vacuum, engine off means no vacuum and no vacuum means no fuel, or at least it should, if all is working properly.

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Mine does the same occasionally, but only when turning the fuel to pri. Gas will just pour out of the airbox side of one carb.

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Mine does the same occasionally, but only when turning the fuel to pri. Gas will just pour out of the airbox side of one carb.

it will not only flood the engine but do damage to the bore as it washes the oil away

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Mine does the same occasionally, but only when turning the fuel to pri. Gas will just pour out of the airbox side of one carb.

This also means that your needle valves in the carb(s) are not sealing. Get a good rebuild kit (one that comes with new needle valves and seats) and get this puppies sealing and you should see a world of difference, and besides you won't be filling the crankcase with gas anymore. When mine did that I decided to actually idle it for about 10 minutes with the gas in there before draining and changing the oil and filter. I know I don't have any gunk built up in the engine now!!! I know there are safer things to use but since the gas was already in there I figured I would take advantage of it (and it worked out fine).

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Unfortunately I don't know much about cleaning/setting/adjusting carbs. Guess I should swing the bike by to see my mechanic. It's runs great, but seems to idle a bit high (approximately 1,800 rpm). Does it idle high because of the carb issue? Also, the title of the bike states it's an '83 but on the bike frame it says the bike was manufactured 5/82. Any thoughts?

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To adjust the floats, you just take the float bowls off on the bottom of the carbs, and there is a tab in the middle of the floats, that contacts the float valve. You want to adjust each carb to the same level. I just blow into the gas line and adjust until they look even. It may take a few times, taking the carbs off the bike. Drewpy mentioned using a hairdryer to soften those boots up on the airbox.

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Also, the title of the bike states it's an '83 but on the bike frame it says the bike was manufactured 5/82. Any thoughts?

pretty common accurance Chicken......

Kind of a Mfg date vs. Title/Reg date type of thing :D

Especially with '81-'83 XS, XJ's.....which they basically sold the same machinery & where cosmetic changes seem to be the only changes during those years :unsure:

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pretty common accurance Chicken......

Kind of a Mfg date vs. Title/Reg date type of thing :D

Especially with '81-'83 XS, XJ's.....which they basically sold the same machinery & where cosmetic changes seem to be the only changes during those years :unsure:

Also the model year starts well before the calendar year. IIRC my 80 was manufactured in late 79. Cars are the same way, but most of them don't show the manufacturing date.

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