99 fat boy. ? About petcock.

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Apr 25, 2021 | 12:19 PM

aperdue

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From: Houston, TX

99 fat boy. ? About petcock.

So I have a vacuum petcock on my fatboy. I noticed that fuel will only come out of the petcock if the engine is turning over. If I twist the throttle, no fuel comes out if it isn’t turning over. Is this normal? If I leave the bike a couple weeks, the only way to fill the bowl is to turn it over a few times to put a vacuum on it.

Apr 25, 2021 | 12:20 PM

Stiggy

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From: Oxford, Nc

That's the design....

Apr 25, 2021 | 12:23 PM

aperdue

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From: Houston, TX

Okay, so simply twisting the throttle will not get the fuel to flow?

Apr 25, 2021 | 12:34 PM

misfitJason

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From: Florida

correct. Not without vacuum, unless it's broken

Apr 25, 2021 | 12:39 PM

aperdue

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Cool, thank you both.

Apr 25, 2021 | 12:58 PM

GOGOBECK

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From: Moneta, Virginia

If there’s fuel in the carburetor bowl, the accelerator pump should shoot fuel into the mouth of the carb when you twist the throttle. It’s how I cold start mine, enricher out and two squirts from the the throttle, thumb the starter button = vroom

Apr 25, 2021 | 05:45 PM

WP50

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From: W. Texas

Quote:

Originally Posted by aperdue

If I leave the bike a couple weeks, the only way to fill the bowl is to turn it over a few times to put a vacuum on it.

Are you having a hard time starting the bike after a couple of weeks??

Lots of us have replaced the vac. operated petcock cause they were known to go bad.

WP