HeresMyMind
04-13-2009, 06:13 PM
So i noticed I had oil clogging my pcv valve quiet often and that the hose from the crank case to the valve had a good 3mm wall of oil caked onto it. I had done some quick searching on oil catch cans and where they should be installed. a common myth is that they belong between our valve covers and the intake hosing that goes to the intake box. WRONG. the valve cover hoses actually suck air IN to the valve covers hence why there is no oil on those hoses near the valve covers. the actual blow by gasses are sucked up from the crank case and they either enter the intake box or the manifold directly through the pcv valve.
When at idle the throttle body is Closed, so the pcv sits open allowing the blow by gases to enter the intake manifold directly through the pcv valve.
when the idle is OPEN the blow-by gasses get sucked in through the intake box itself. the PCV valve is closed.
SO i found that the best place to install an oil catch can is between the crank and the plastic fitting that T's going to the manifold/air box. This will actually prevent the oil from going into the manifold at all.
https://sl-i.net/FORUM/images/imported/2009/04/2cctnhf-1.jpg
For us N/A people that helps explain some of the mystery of where our oil goes.
now there are 2 different styles of oil catch cans.
1) with fittings only on the top/side. 1 for vacuum the other for the pcv valve hose. oil comes in then falls to the bottom. Drain when filled.
https://sl-i.net/FORUM/images/imported/2009/04/42ac_1JPG-1.jpg
2) fittings on the top and the bottom. (Crawford oil separate for example) the Top is vacuum, the sides are where the blow by gasses enter. the very bottom is so that the oil can drain back into the valve covers. This prevents Oil loss. The oil that drains back into the valve covers isn't burnt or bad. it is in the same condition that the oil in your oil pan is. The oil just seeped by the pistons.
http://store.crawfordperformance.com/system/uploads/415.jpg?1229730127
I hope this helps some people better understand the pcv system and where a Oil separator should be installed. I plan on doing mine within the week and will post results when done!
-B
When at idle the throttle body is Closed, so the pcv sits open allowing the blow by gases to enter the intake manifold directly through the pcv valve.
when the idle is OPEN the blow-by gasses get sucked in through the intake box itself. the PCV valve is closed.
SO i found that the best place to install an oil catch can is between the crank and the plastic fitting that T's going to the manifold/air box. This will actually prevent the oil from going into the manifold at all.
https://sl-i.net/FORUM/images/imported/2009/04/2cctnhf-1.jpg
For us N/A people that helps explain some of the mystery of where our oil goes.
now there are 2 different styles of oil catch cans.
1) with fittings only on the top/side. 1 for vacuum the other for the pcv valve hose. oil comes in then falls to the bottom. Drain when filled.
https://sl-i.net/FORUM/images/imported/2009/04/42ac_1JPG-1.jpg
2) fittings on the top and the bottom. (Crawford oil separate for example) the Top is vacuum, the sides are where the blow by gasses enter. the very bottom is so that the oil can drain back into the valve covers. This prevents Oil loss. The oil that drains back into the valve covers isn't burnt or bad. it is in the same condition that the oil in your oil pan is. The oil just seeped by the pistons.
http://store.crawfordperformance.com/system/uploads/415.jpg?1229730127
I hope this helps some people better understand the pcv system and where a Oil separator should be installed. I plan on doing mine within the week and will post results when done!
-B