Crankcase venting

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Jul 27, 2020 | 12:14 PM

twincam10353

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From: New England

Crankcase venting

Looking at Feuling's vented dipstick for my 16 FLHXS. If I went this route, would it eliminate the need of an external breather system for my air cleaner? Or would you run both systems together?

Jul 27, 2020 | 05:15 PM

60Gunner

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From: Dubuque, IA

I wouldn't vent out the dipstick or any lines running out of the oil tank. I also wouldn't vent out of 2 different locations.
IMO, the best place to vent is the cam chest. As it is, crankcase pressure travels up the same place oil runs down. The pushrod tubes.

Jul 27, 2020 | 05:52 PM

jonuphi

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From: florida

I vented my crankcase on my 18 after my 1st engine sumped at 7000,have almost 22000 on it now and have never felt a hint of sumping on this engine.i run it a half qt down also that's where it levels out and doesn't drip out the vent,seems to work for me

Jul 27, 2020 | 07:03 PM

60Gunner

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From: Dubuque, IA

Quote:

Originally Posted by jonuphi

I vented my Sporty out the cam chest after blowing rockers cover gaskets 3 times in 1000 miles and head gaskets weep on the dyno after a build and realizing the problem was my stock umbrella valves were shot. Drilled and tapped a hole in the cover for a 90° 1/8 npt fitting and ran the Hayden Krankvent. I plugged the head breathers with solid bolts. Problem solved and no more hoses dangling from the heads.
The difference was immediately noticeable on startup the way idled even. There's a detailed write up with pics on the XL forums on this. Quite a few Sporty owners, especially with builds, run this mod. I haven't done anything with my Softail yet.

Here's a pic. It was pretty much hidden too.

Last edited by 60Gunner; Jul 27, 2020 at 07:14 PM.

Jul 28, 2020 | 06:05 AM

prodrag1320

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From: deland,florida

if you did vent it it with the dip stick (really no difference in venting there or the cam chest) it would not make getting rid of the head breathers a good idea,run them both

Jul 28, 2020 | 09:05 AM

twincam10353

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From: New England

Quote:

Originally Posted by prodrag1320

if you did vent it it with the dip stick (really no difference in venting there or the cam chest) it would not make getting rid of the head breathers a good idea,run them both

Pro, how do you vent your personal street bike?

Jul 28, 2020 | 11:56 PM

60Gunner

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From: Dubuque, IA

Venting out the hose that vents the tank to the cam chest resulted in excessive oil being vented out during hard braking when the oil level reached that fitting at tiimes according to a few that did it on the sportys.
I havent got into the oiling on these twincams much yet but on the sporty evos venting out both ends wasn't necessary when the and the consensus was scavenging could be an issue in a motor that already had scavenging issues. In fact I replaced the pump with the Buell/07+ pump with bigger scavenge gerators as it was.
I'm just not sure how much wet sumping might be an issue with the TCs. Why I haven't done anything yet.
If you vent out both ends, post how that works out. Personally, eliminating the stock breathers if possible is a plus imo.
I assume Prodrag is venting out both ends without any issues so.

Last edited by 60Gunner; Jul 29, 2020 at 12:15 AM.