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Cv 40 problems

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Old Jun 18, 2016 | 09:01 PM
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Default Cv 40 problems

I have an 06 fatboy. While riding my bike backfires really loudly unless I have the choke at least half way out. When idling I have to have the choke out a bit or it will stall and when I turn the throttle slowly it will sputter and stall out, same goes for when I'm driving but when I Crack the throttle back it goes no problem. I've rn seafoam through it, took the carb apart and changed the insides of it. Also have swapped the fuel filter but it is still doing it.

Update. I found that there is a intake leak on the bottom end of the intake where the carb inserts. I bought a new gasket but am having the same issues. Does the carburetor flange warp or bend over time? 24k on the bike
 

Last edited by Gary Jarvis; Jun 18, 2016 at 09:03 PM.
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Old Jun 19, 2016 | 01:52 PM
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Loosely fit the intake manifold to the intakes on the heads, then install the carb and air cleaner backplate with the breather bolts into the heads. Then tighten the intake manifold fasteners to spec. This aligns the intake manifold to the proper location for the carb.
 

Last edited by Zanthamos; Jun 19, 2016 at 01:55 PM. Reason: New information
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Old Jun 24, 2016 | 04:26 AM
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Did you check for intake manifold leaks?
 
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Old Jun 26, 2016 | 08:28 AM
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Ok last night I replaced the 2 gaskets that are against the motor and it was running good and I could even roll the throttle slowly but after about 3 min I couldn't roll the throttle slowly with out it choking out and stalling.
 
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Old Jun 26, 2016 | 08:59 AM
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Kinda sounds like your pilot jet is clogged. If you have to pull the choke out slightly to run, you have an extremely lean condition and/or a intake leak somewhere. Did you remove the jets when you cleaned the carb?
 
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Old Jun 26, 2016 | 09:08 AM
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I actually replaced the pilot yesterday
 
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Old Jun 26, 2016 | 08:07 PM
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I presume you have blocked off the VOES or vacuum petcock holes (or at least double check these for cracks or air leaks)
 
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Old Jun 26, 2016 | 09:17 PM
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I have no voes. I did not check the petcock
 
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Old Jun 26, 2016 | 11:48 PM
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The connector is at the back of the carb and should have a rubber plug over it if its not being used.
 
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Old Jun 28, 2016 | 05:17 AM
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Air/idle mixture screw out 2 1/2-3 turns.
48-50 pilot baseline jetting.
Scott
 
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