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Discussion Starter #1
I am new at trying to do my own work on my bike and have a lot to learn. I am haveing problems with my carbs, I think it could be a stuck float but before I remove the carbs I wanted to cover anything else. From what I have read the carb vent tube comes from each carb (in between them) to a T then runs back towards the seat or to the airbox, correct? The reason I am unsure is that when I took the tank off I saw the fuel gauge box that has two wires comeing out of it and a port that looks like a tube would go on it but nothing was hooked to it. I saw what I now think is the vent tube in that area and thought that it might go the fuel gauge. Is there something that should be hooked to the fuel gauge box? Problem started when bike all of a sudden started to idel faster on its own then it started dogging out acting like it wasn't getting gas but I could smell gas quite strong then it died. I got it running angain and noticed gas running down over the rear cylinder head. Now I am pretty sure it was comeing out of the carb vent tube. I just got a MF batt. and more sea foam. Thanks for any ideas or suggestions.
 

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Kawika
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I'm pretty sure that nothing is supposed to be connected to the fuel gauge...there is a nipple there, but nothing was plugged into mine from the day I bought it. I would check the fuel tank vent to see if it's plugged, too.

good luck!:smiley_th
 

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Just out of curiosity, what year is it? I've seen several of the early year bikes with the vent tube run to the nipple on the fuel sending unit cover, straight from the dealer's showroom, FWIW, altho the manual does show the vent slipped into the lower slot on the right ear.

Mine's shaved, and the vent tube run into the area between the upper frame tubes near the steering head. It's a '95, and originally went to the right ear. A friend of mine has a '86 that has the tube run to the nipple on the sending unit cover, and my '87 did also.

Jim


I am new at trying to do my own work on my bike and have a lot to learn. I am haveing problems with my carbs, I think it could be a stuck float but before I remove the carbs I wanted to cover anything else. From what I have read the carb vent tube comes from each carb (in between them) to a T then runs back towards the seat or to the airbox, correct? The reason I am unsure is that when I took the tank off I saw the fuel gauge box that has two wires comeing out of it and a port that looks like a tube would go on it but nothing was hooked to it. I saw what I now think is the vent tube in that area and thought that it might go the fuel gauge. Is there something that should be hooked to the fuel gauge box? Problem started when bike all of a sudden started to idel faster on its own then it started dogging out acting like it wasn't getting gas but I could smell gas quite strong then it died. I got it running angain and noticed gas running down over the rear cylinder head. Now I am pretty sure it was comeing out of the carb vent tube. I just got a MF batt. and more sea foam. Thanks for any ideas or suggestions.
 

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Problem started when bike all of a sudden started to idle faster on its own then it started dogging out acting like it wasn't getting gas but I could smell gas quite strong then it died. I got it running again and noticed gas running down over the rear cylinder head. Now I am pretty sure it was comeing out of the carb vent tube.QUOTE]

Yep; BTDT. Definitely sounds like a stuck float needle. Should've sounded like it was only running on one cylinder, too.

Trash, dirt, etc., somehow gets into the float chamber, and eventually into the needle seat, keeping the float needle from closing; won't go thru the system, and won't get the heck outa the seat, either.

Before you start tearing the carbs outa there, try draining the carb for the cylinder that's acting up, then filling it thru the drain with Seafoam until it comes out the vent tube. You'll need some 3/16" clear tubing from the small engine section at the parts house, or 3/16" fuel hose; doesn't necessarily have to be clear. Make it long enuff that the end is higher than the frame. You'll also need to extend the end of the vent tube to the side enuff to keep the Seafoam from spilling out onto the bike--use a can or jar on a small stand of some kind under the end of it; and stick some shop rags or towels under the carbs to keep it from running all over the engine.

Pouring Seafoam into the tubing with a small funnel (Coleman stove funnel is perfect), close off the drain when the Seafoam starts coming out the vent tube. Let it sit for a five or ten minutes, then open the drain. When it quits, close the drain. I'd do the same with the other carb, just for grins, since I'm down there anyway.

I'd go ahead and pull the petcock off of the tank and make sure there's no trash in it, too, and that the screen(s) are clean.

Once you're done, hook everything back up, choke it, and see if she runs like she's supposed to. If she does, and then starts acting up again, you're prolly gonna have to bite the bullet and go ahead and pull the carbs and clean 'em right.

Jim
 

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Discussion Starter #5
Thanks for the advice J.D. The bike is a 1991, I am going to the parts store now to get some tubeing and try what you said. I have already had the pet cock apart and it was pretty clean, nothing on or in the screens. I have to change the o-rings on the cooling line today and soak the carbs in seafoam before work (1:00pm) so probly won't try to start it today, but day off tomarrow. I'll let you know how I make out. Thanks again.
 

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Discussion Starter #6
Well, I filled the carbs through the drain until it came out the vent tube with seafoam and let it sit for about 20 minutes or so. I drained the bowls and put fresh gas in the tank and tried to start it, it started but not real easy and it ran real rough and smoked really bad. It would not idel with out giveing it some throtel. Had to use the choke to start it initially, which I have always had to. I shut it off and tried to start it again and it wouldn't. Also noticed the headlight wasn't on, the other lights were on. Not sure what that means. I appreciate any ideas or suggestions. THANKS, :confused:
 

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The proper fix is to remove the carbs and clean and inspect them.
 

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Discussion Starter #9
stuck float

Thanks for the suggestions, found that the front cylinder carb had a black speck of something in it makeing the float stick. Clean carbs, new plugs, oil and filter should be good to go now. Thanks again!
 

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Having the exact same problem, and am pulling the carbs now. Even had that no start problem, with everything lighting up BUT the headlight. Going to be going over battery connections and stuff too...

I had a tube plugged into the nipple of that square connector, in the bottom-center of the tank. I didn't have anything plugged into the right hand air box. (like the photo in the Cylmer's)

(Then there's that little exposed nipple right of the top side, very back off the tank, that is hidden by the seat; I didn't have anything connected to it either.)
 
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