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CV Carburetor Problems

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Old Feb 26, 2017 | 11:43 AM
  #1  
Range's Avatar
Range
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From: USAG Bavaria Rose Barracks Army Post
Default CV Carburetor Problems

I recently tuned up my 2003 Sportster 1200C and everything worked out fine. Until I rebuilt the carburetor. It was my 1st time doing so and now the bike wont start. I have redone it three times meticulously ensuring I do it properly and check all parts and seals as instructed in several different videos on youtube. Everything seems to be done properly but the carb isnt getting any fuel.

The bike just cycles and wont start. If i spray some starting fluid in it in turns over a few times and then stalls. After trying to start it until the battery dies, and priming it, when I remove it to check its construction it is dry of fuel. One thing I noticed was that with the fuel line removed from the petcock, and the petcock open, no fuel comes out of the petcock. Could this be the problem? I thought maybe but it seemed far too much of a coincidence. Does the carbureator suck the fuel out of the petcock?

Anyway Im stationed in Germany so taking my bike to a german HD place will probably cost 5x what it would stateside. I hope I can fix it with your help. Thanks.
 
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Old Feb 26, 2017 | 04:02 PM
  #2  
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Campy Roadie
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Do you have the vacuum line attached to the petcock?

Have you checked the diaphragm in the petcock?

Is the petcock in the ON position?
 
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Old Feb 27, 2017 | 11:54 AM
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From: USAG Bavaria Rose Barracks Army Post
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I haven't checked the diaphragm on the petcock, as it was working fine before I took the carb apart. The petcock is also in the on position and there is plenty of fuel in the tank. There is a vacuum line attached to the petcock. In the videos I watched on carb rebuild the bikes started up with minimal priming, i.e. some starting fluid past the butterfly. Does the carb need to be filled with fuel all the way to the float shutting off the input of fuel into the carb for the bike to start? If so how do I cause the petcock to fill the carb to the necessary level without vacuum pressure to the petcock? There is no prime setting on the petcock. Intuitively I would guess that removing the vacume line from the petcock and sucking on it to replicate the suction provided by the carb- but this is my first time at this job so Im not sure if I can provide the necessary suction or if there is a better way to prime the carb to the necessary fuel level.
 
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Old Feb 27, 2017 | 05:30 PM
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Mike Lawless
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Turn it to reserve. That should allow fuel to flow. Once the carb bowl has fuel in it, you can return it to "on"
 
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Old Feb 28, 2017 | 07:28 AM
  #5  
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From: USAG Bavaria Rose Barracks Army Post
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Turning it to reserve did nothing. The petcock still relies on vaccume pressure created by the carb to allow the fuel to flow. I had to take a long piece of vacuum tube and attach it to the back of the petcock and suck on it to open the valve and allow fuel to flow into the carb. Once I did this it started right up.

Im getting a new aftermarket petcock with a prime setting on it and a clear fuel line.
 
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Old Feb 28, 2017 | 12:22 PM
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Mike Lawless
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That's weird. I had a 2002 Sporty, and reserve worked just fine to get the fuel flowing.

Glad you got it sorted.
 
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