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Ideas for re-routing blow-by with SE/AC

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Old Aug 11, 2017 | 12:36 PM
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Originally Posted by T^2
... Umbrella valves have a reputation for having a short effective life span.
Whoa, good to know. How do I check that the umbrella valves are still ok?
 
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Old Aug 11, 2017 | 12:59 PM
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Originally Posted by lewk
Whoa, good to know. How do I check that the umbrella valves are still ok?
One symptom would likely be excessive puking of oil. For more information I might do a couple searches on the subject... Google search terms...

umbrella valves site:xlforum.net
umbrella valves site:hdforums.com
Deimus did a thread over on XLForums called "Installing the ultimate crankcase vent “How To”"

http://xlforum.net/vbportal/forums/s...ad.php?t=72099

I'm not advocating one way or another about that approach. However, that thread has some good information in it. It also has some bad info as it goes along that later gets ferreted out (so keep reading).

I thought the Deimus approach may be more hassle than what was necessary. So I just used a DK Customs bypass kit with the addition of a Krankvent to account for potential failing umbrella valves. You can see it here:

https://www.hdforums.com/forum/sport...l#post16508343

Like I said in that post...

The down side - if there really is any - is that this setup still breaths via the push rod tubes etc. Opinions probably vary as to if that really matters
 
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Old Aug 11, 2017 | 02:17 PM
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Originally Posted by T^2
One thing to consider with the above approaches. None account for failing umbrella valves. Umbrella valves have a reputation for having a short effective life span.
I dont have excessive blow-by just want to reroute the blow-by that I do have on the SE/AC to a catch can instead of the intake. Now if I started having excessive blow by where I was loosing alot of oil I would check the umbrella valves.
 
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Old Aug 11, 2017 | 03:41 PM
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Originally Posted by onelocoman
I dont have excessive blow-by just want to reroute the blow-by that I do have on the SE/AC to a catch can instead of the intake. Now if I started having excessive blow by where I was loosing alot of oil I would check the umbrella valves.
That's fine... But the main purpose of the umbrella valves is to create a vacuum in the crank case (letting air out and preventing air from being sucked back in). Consider the possibility that they could be failing (partially or completely) in that regard and yet you still might not see much oil coming out of your breathers for various reasons.
 
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Old Aug 11, 2017 | 08:40 PM
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Originally Posted by T^2
That's fine... But the main purpose of the umbrella valves is to create a vacuum in the crank case (letting air out and preventing air from being sucked back in). Consider the possibility that they could be failing (partially or completely) in that regard and yet you still might not see much oil coming out of your breathers for various reasons.


Curious, are the umbrella valves susceptible to short lifespan or failure even with the original design intent of oil and water being dumped into the throttle intake?
 
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Old Aug 11, 2017 | 09:20 PM
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Originally Posted by Grey_Beard
Curious, are the umbrella valves susceptible to short lifespan or failure even with the original design intent of oil and water being dumped into the throttle intake?
The lifespan of the umbrella valves has nothing to do with where the venting is routed.

The routing of the venting to the intake has to do with satisfying the EPA.
 
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Old Aug 11, 2017 | 10:00 PM
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Originally Posted by T^2
The lifespan of the umbrella valves has nothing to do with where the venting is routed.

The routing of the venting to the intake has to do with satisfying the EPA.


Appreciate it. I know it's to keep the EPA happy, was hoping that the re-routing didn't accelerate the valves life span.
 
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Old Aug 12, 2017 | 07:37 AM
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Originally Posted by lewk
Whoa, good to know. How do I check that the umbrella valves are still ok?
One method to test if the umbrella vales are working is to: While draining crankcase oil, leave the fill plug tight, as it is draining, loosen fill plug and oil flow should increase. If it does not, they are not closing/sealing.
 
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Old Aug 15, 2017 | 03:04 PM
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Got in from vacation last night and my stuff from DK customs came in.

So here it is.
 
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Old Aug 15, 2017 | 07:59 PM
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Originally Posted by onelocoman
Got in from vacation last night and my stuff from DK customs came in.

So here it is.


Looks good with the catch can I like it.
 
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