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Crank Case Vent

1463 Views 7 Replies 5 Participants Last post by  RedDogg
So.... now I have installed my ProDesign pro flow kit w/K&N filter. The instructions say to pull the crank case vent hose out @1/2 inch. This allows the K&N filter to fit, but will dirt get into my crank case through this hose? I think the flow of air comes out of this hose, but now there is no negative pressure (vacuum) from the motor. I'm sure some gasses may come out as the piston moves down, but will it draw in dirt as it moves up? Also, no airbox lid. I'm open to any thoughts, opinions, experiences, or flat out correct answers. Maybe a breather filter should be placed on the hose.... or maybe I'm just paranoid! What has everyone done with this hose?
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K&N makes a little filter for that vent.
My buddy has one on his Pred.

I don't think I'd leave that line open.
One more reason NOT to use a K&N!

I'll wait for a few more replies. If this hose is going to be a hastle, then I will just go with a foam filter. Will the Uni filter work with the ProDesign pro flow billet plenum? If not, what will I need?
I use the UNI.

I'm a dunner and ride in the sand.
The K&N filter flows fine but doesn't filter that well.

just cut a piece of the stock filter and put it in between the hose and the k&n
I shoved mine up against my K&N and it ran just fine and never had anything get in it...... i was going to get one of those little breather filters but i got the sparks racing filter instead and it eliminated that problem......
mine is against the k&n
Thanks for the suggestions. For now I have pushed the hose tight against the filter and I will start looking for a good price on the Uni. Still don't know if I need a special adapter for the Uni. Do I need to run with a prefilter over the Uni w/o airbox lid? :mellow:
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