Carb Float Needle Valve - Tests & Tips - Kawasaki Vulcan 750 Forum : Kawasaki VN750 Forums
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post #1 of 2 (permalink) Old 09-30-2011, 12:16 AM Thread Starter
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Carb Float Needle Valve - Tests & Tips

Was helping a friend rework his carbs today and after we finished we checked the fuel levels in each carb... they were right on the money! He started to put the carbs back on the bike, i told him to stop and asked if he had checked for "leak by", meaning for air leaks or fuel leaks, by the float needle valve. He asked me how do you check that.
I explained to him that after checking the fuel levels that he needed to drain all fuel from the carbs and be sure there wasnt any left in the carbs. Then i explained to him how to check for a positive seal on each carb that has a float needle valve.
Turn the carbs upside down,, blow lightly into a very long hose that is clamped on and to the fuel inlets on each carb. make sure the bowl drain plugs are closed. If you cant blow or suck air thru the carb,, then you have a positive seal. If you can blow or suck air thru any of the carbs then the needle or seat is in bad shape, check it out before putting the carbs back on and then having more headaches and having to pull carbs again.
I alway do this and it has worked for me just thought i would pass on another tip i have always used. Thanks to all the folks here on the forums for all of their support and ideas!!!

Vulcan #1 1993 - 28K
Vulcan #2 1999 - 26k
It All Comes Down To 3 Things:
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post #2 of 2 (permalink) Old 09-30-2011, 05:29 AM
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Sucking thru the hose I can see; blowing thru it I would think you could still lift the needle out of the seat. Good tip, tho; one I hadn't ever thought of, as many times as I've had CVK carbs apart.

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