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Old 08-06-2019, 11:20 AM
vybrano vybrano is offline
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Default How does vented gas cap works; should it smell?

Working today around my ride I noticed, that if you put your nose 7inch/15cm from my gas cap, you can strongly smell fuel.

There's also some mechanism in the cap - probably ball that prevents leaks in upside down position? Or is it something more to it? Could it be bad cap that is evaporating my fuel. Or is it completely normal? I understand that it has to vent tank, but still, should I start looking into it or is it normal?

I wouldn't ask - but it is second hand tank and there are signs, that somebody was inside that cap before me (stripped screw head; glue) - which got me thinking why and what was done and how good... .
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Old 08-06-2019, 11:43 AM
mckutzy mckutzy is offline
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Ya.. I typically smell fuel when im that close to the tank... you will smell it through the breather...

Some have a ball or membrane/diaphram to allow the air to escape.... But enough of a gap to not air lock the fuel line... or it wouldnt flow into the carb...
10yr+ club..... My current ride- http://www.diygokarts.com/vb/showthread.php?t=5461
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Old 08-06-2019, 09:40 PM
Karttekk Karttekk is offline
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As much as a cap costs, why don't you pick up a new one to be sure? If yours was tampered with, who knows if it's working. The caps have to vent so as the fuel is being drawn into the carb air can be drawn in from the cap as a vacuum.
Old 08-08-2019, 11:07 AM
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JTSpeedDemon JTSpeedDemon is offline
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My kart's gas cap has a screw vent, and the kart usually emanates a gassy smell.
Got me banned from long term garage storage.
Currently Flathead-Crazed
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