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External breather for AC/DC or Stealth aircleaner?

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Old Mar 14, 2021 | 10:13 PM
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Default External breather for AC/DC or Stealth aircleaner?

Looking for recommendations for an external breather for Fuel Moto AC/DC or S&S Stealth aircleaner. I'm running my oil level 4 holes down from full on the dipstick and still getting quite a bit of oil in the AC/DC airfilter. I know there are kits available to drill and tap the air filter backing plate to install nipples to run vent lines. But the AC/DC and S&S Stealth are both a composite backing plate with brass inserts where the breather bolts go. Not sure if a drill and tap kit would work with this sort of backing plate. Has anyone done an external breather on these airfilters?
 
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Old Mar 15, 2021 | 06:23 AM
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Originally Posted by desertwolf
Looking for recommendations for an external breather for Fuel Moto AC/DC or S&S Stealth aircleaner. I'm running my oil level 4 holes down from full on the dipstick and still getting quite a bit of oil in the AC/DC airfilter. I know there are kits available to drill and tap the air filter backing plate to install nipples to run vent lines. But the AC/DC and S&S Stealth are both a composite backing plate with brass inserts where the breather bolts go. Not sure if a drill and tap kit would work with this sort of backing plate. Has anyone done an external breather on these airfilters?
What bike & Year? I had the issue on my ‘17 w 117” build and vented the oil sump (dipstick) and it cleaned it all up. Easier!!!
 
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Old Mar 15, 2021 | 07:08 AM
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Originally Posted by desertwolf
Looking for recommendations for an external breather for Fuel Moto AC/DC or S&S Stealth aircleaner. I'm running my oil level 4 holes down from full on the dipstick and still getting quite a bit of oil in the AC/DC airfilter. I know there are kits available to drill and tap the air filter backing plate to install nipples to run vent lines. But the AC/DC and S&S Stealth are both a composite backing plate with brass inserts where the breather bolts go. Not sure if a drill and tap kit would work with this sort of backing plate. Has anyone done an external breather on these airfilters?
Im looking at doing the same exact external breather setup with my S&S Stealth intake. The issue I see with the S&S and AC/DC is how the breather holes are not directing the oil back into the intake like the HD intake does with the rubber hoses. The oil from the S&S just sort of drips down and not necessarily is directed back into the intake throat via a rubber hose barb. Either way, I’m looking to make this an external breather set up.

I do think I’ve seen people drill and tap the composite/brass intake just as they would with an aluminum one....
 
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Old Mar 15, 2021 | 07:42 AM
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If you use a bulkhead fitting you won't need to drill/tap. I used these -
Amazon Amazon
 
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Old Mar 15, 2021 | 08:51 AM
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Originally Posted by 702
If you use a bulkhead fitting you won't need to drill/tap. I used these - https://www.amazon.com/gp/product/B07Q3D8XGZ/
How the hell did you get the nut on the inside of the breather bolt hole?
 
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Old Mar 15, 2021 | 09:02 AM
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I did my stealth in the exact same manner as my other, drill/tapped for push connect fittings and plugging the ports that lead into the intake
photo is of my previous setup but the method is the same

 
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Old Mar 15, 2021 | 10:04 AM
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Bike is a 20 RGS 114
 
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Old Mar 15, 2021 | 11:45 AM
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I have the FM/S&S AC/DC / Stealth air cleaner on two bikes with big displacement builds. I thought about drilling, tapping, etc, but decided to use the Harley OEM breather bolts instead.

Install has yet to occur, but I have the bolts, just need to pick up some tubing and fittings, and decide on a catch can or breather filter.

These are the bolts I'm talking about.


 
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Old Mar 15, 2021 | 06:43 PM
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Originally Posted by GlidingJoe
What bike & Year? I had the issue on my ‘17 w 117” build and vented the oil sump (dipstick) and it cleaned it all up. Easier!!!
Which dipstick vent did you use?
 
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Old Mar 16, 2021 | 06:44 AM
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my stealth ac, drilled and tapped for fittings
 
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