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Vacuum Leak

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Old 09-24-2008, 05:14 PM
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Default Vacuum Leak

Hello

I believe I have a vacuum leak on my '99.

I replaced all the tubing from the carb to the EOS and the petcock, (all dry and cracked and somebody taped it) but the idle still likes to go high and hang there. Still poofs occasionally when coming in for a landing too.

Where else could it be leaking? I don't really want to hose it down with WD-40.

Or what else could manifest itself with those symptoms.

Still getting acquainted with (her/him) it. The Lady in Red. No, she won't do windows but she looks goooood.

Thanks
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Old 09-24-2008, 07:34 PM
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carb gasket?
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Old 09-24-2008, 08:15 PM
Doug45601 Doug45601 is offline
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Mine (also a 99) acted up that way and I found it to be the rubber bladder had worn out in the carb. Actually had a small torn place in it allowing the carb to suck in air.
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Old 09-24-2008, 08:59 PM
JosephGarcia JosephGarcia is offline
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check the diaphragm in the carb and replace your intake manifold seals and the carb to intake seal. the intake to cylinder head seals dont last too long becuase of the design.
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Old 09-24-2008, 11:01 PM
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+1 on what Joseph said also while you are in the carb go ahead a replace the diaphragm in the accelerator pump, Thats where that little rod goes into the top of the float bowl.
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Old 09-25-2008, 01:04 PM
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Thanks to all for the input.

I will go ahead and tear the carb off. I've wanted to see what other hacker mods it's previous owner made. I suspect it has larger jets and maybe the needle has been jacked-up.

I do agree that the rubber parts don't last forever, so I'm certain the advice is all good. I may do the diaphragm in the petcock while I'm at it.

The VOS.. is that mearly a set of switch contacts that open or close when vaccum is applied? Can it be checked with a VOM?

Thanks again for all the help.
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Old 09-25-2008, 01:38 PM
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You can check your VOES switch with a Ohm meter and vacuum pump.You need the vacuum pump to create the vacuum of 3.5 to 4.5 inches. The ohm meter should read zero when the vacuum is between these settings. If a higher (than 4.5 inches) or lower (less than 3.5 inches) value is required to to close the switch (zero reading) the switch needs replacing. You may also only need to replace the VOES hose, I believe HD sells this separately, as it may be cracked or worn out.
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Old 11-05-2016, 11:01 PM
maxim22 maxim22 is offline
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How do poeple get around having all this stuff on their bikes if they want a clean looking bike tat still runs well do they install a switch to retard the timing for a short amount of time durring warm up. any thoughts on this? also what wires would need the switch?
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Old 11-05-2016, 11:09 PM
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Quote:
Originally Posted by maxim22 View Post
How do poeple get around having all this stuff on their bikes if they want a clean looking bike tat still runs well do they install a switch to retard the timing for a short amount of time durring warm up. any thoughts on this? also what wires would need the switch?
Start a thread or make a few posts if you need to. Then tell us what year and model Sportster you have. Pic?
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Old 11-05-2016, 11:12 PM
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Quote:
Originally Posted by Sundog View Post
Thanks to all for the input.

I will go ahead and tear the carb off. I've wanted to see what other hacker mods it's previous owner made. I suspect it has larger jets and maybe the needle has been jacked-up.

I do agree that the rubber parts don't last forever, so I'm certain the advice is all good. I may do the diaphragm in the petcock while I'm at it.

The VOS.. is that mearly a set of switch contacts that open or close when vaccum is applied? Can it be checked with a VOM?

Thanks again for all the help.
Quote: Who needs chrome? Ditch the battery cover and just use the clamp. Dig your bike.
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1985, 2002, 883cc, check, davidson, fix, harley, idles, king, leak, problem, road, sportster, switch, vacume, vacuum, voes, xl

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