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Anyone have pics of underside of valve cover?

24K views 27 replies 9 participants last post by  lnxpeng 
Awesome, thank you. This looks metallic (mine is the polymer one in 2005), but I bet it's similar. How the heck can those baffles move enough to let a lot of oil through? I could see how a little might escape, but I was not expecting it to look like that.

Thanks for the photos!
Same question. HOW does oil flow like a faucet through that. How does oil in engine defy gravity?
 
Excessive blow-by can cause a steady stream of air to flow out of the breather. At that point, the oil is just along for the ride.
Yea I know, you helped with my problems I was having haha. Sometimes the amount I was losing seemed unreal.

I'm guessing under that metallic shield, it's an orifice? There's no check valve or anything, right?

I'm still really confused as to why both sides (which are connected inside the head) are needed. Can I plug one side, put a T-connector on the other, and run one hose to the intake before the TB, and one hose to the intake manifold?

I've heard so many conflicting things about this system. I'm thoroughly confused. I recently heard (here) that the intake tube picks up air inside the intake manifold (like a Pitot tube) and air flows from the intake manifold to the valve cover, then air can vent from the valve cover to the TB.

It's confusing. And also getting a thin film of oil in my intake, so I want to solve it. I need a way of figuring out air flow direction in an air line. Seems like a good science project.
The direction of air flow is from passenger side (fresh air inlet) to driver side (dirty air). Some guys have vented it to atmosphere, which if you dont have excessive blow by is okay. If you have low compression on any cylinder causing blowby you will end up with the entire bottom side of of your pickup (and maybe even the side of your truck) coated in oil.
 
Ok, thanks. That helps. Why do I have oil in my breather then? What conditions would cause crankcase pressure to be higher than intake pressure?

I'm thinking (now) that I'll add a catch can on the intake side, and put a check valve on the exhaust side, that only allows airflow from intake to valve cover.

If it needs to relieve pressure from that line (I can't see why unless the other side was clogged, though), maybe I can put another check valve that vented positive pressure to the air (through another can that wouldn't get oil everywhere), just in case it needs airflow in both directions on the exhaust side.
If you are getting excessive oil usage check compression.
 
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