Oil Separator/PCV system

[Chris]

Who uses one and if so which do you use?

I’d seen this which looks smart and simple to use:

https://www.moroso.com/catalog/product/view/id/8318/s/air-oil-separator-kit-large-body85514/

With the intention of running valve cover to separator, then to vacuum on intake manifold.

Will be running windage tray and crank scraper in the sump on a 347 stroker.
Anyone ever had crankcase pressure issues?

 

[Joel Heinke]

I had crankcase pressure issues in my Ferrari 250 GTO replica that has an LS3 motor in it. The symptom was oil leaking from various bottom end seals. I put a M/E Wagner dual flow adjustable PCV in and after getting it dialed in, no more excessive crankcase pressure. A lot of Cobra guys use the Wagner PCV in combination with an oil separator. I had put extensive baffling in the valve cover so I didn't have an issue with oil going up the PCV on my GTO. The Wagner PCV ( http://mewagner.com/ ) is pricey but worth it from my experience.

 

[JP Verweij]

With the intention of running valve cover to separator, then to vacuum on intake manifold.

On both my race cars I have this system, plumbed in as described. It can be any cannister with two connections on top and a drain valve below, bought for as cheap at $20 on ebay.

 

[Chris]

On both my race cars I have this system, plumbed in as described. It can be any cannister with two connections on top and a drain valve below, bought for as cheap at $20 on ebay.

Nice to know, would rather not spend $200 on essentially a catch can where I can avoid it!
If it was the only way I was tempted to stick a filter on each cover and see how it went.

 

[Jac Mac]

On both my race cars I have this system, plumbed in as described. It can be any cannister with two connections on top and a drain valve below, bought for as cheap at $20 on ebay.

Why not convert to a permanent dynamic drain system, dont have to remember to drain that tiny container then. That assumes the engine has been built properly and has low leak down numbers.

 

[Chris]

Why not convert to a permanent dynamic drain system, dont have to remember to drain that tiny container then. That assumes the engine has been built properly and has low leak down numbers.

so you mean a hose going to the floor? Haha.
I’m hoping it won’t have much blow by that’s for sure!

 

[Jac Mac]

so you mean a hose going to the floor? Haha.
I’m hoping it won’t have much blow by that’s for sure!

Hoping, you reckon that will work?

 

[Chris]

Hoping, you reckon that will work?

well my luck isn’t the greatest so I’ll just have to go with a good builder!

 

[DaveC]

Agree with the above, especially the price. I wouldn't spend over $40. On my 489hp LS1 vette, I would routinely put 2-3 oz of oil into my catch can during a track driving session. Beats all that oil going into the intake as designed by the GM PCV system! The problem isn't blow-by, it's oil sitting up in the heads and then blowing out the PCV.

 

[Jac Mac]

Agree with the above, especially the price. I wouldn't spend over $40. On my 489hp LS1 vette, I would routinely put 2-3 oz of oil into my catch can during a track driving session. Beats all that oil going into the intake as designed by the GM PCV system! The problem isn't blow-by, it's oil sitting up in the heads and then blowing out the PCV.

No, your problems are that the breather hoses are in the wrong location and you are not providing a means for the oil in the catch tank/s to return to the pan while operating the car.

 

[DaveC]

No, your problems are that the breather hoses are in the wrong location and you are not providing a means for the oil in the catch tank/s to return to the pan while operating the car.

Using the factory breather locations, but I'm open to your fix. Yes you do have the option of running a line back to your oil pan, but since mine is a track-only issue with high-g cornering at high RPM I don't need it. And I like to monitor what is happening from a volume standpoint.

 

[Scott Davis]

I had crankcase pressure issues in my Ferrari 250 GTO replica that has an LS3 motor in it. The symptom was oil leaking from various bottom end seals. I put a M/E Wagner dual flow adjustable PCV in and after getting it dialed in, no more excessive crankcase pressure. A lot of Cobra guys use the Wagner PCV in combination with an oil separator. I had put extensive baffling in the valve cover so I didn't have an issue with oil going up the PCV on my GTO. The Wagner PCV ( http://mewagner.com/ ) is pricey but worth it from my experience.

Do you have images or suggestions on plumbing the Wagner PCV into the LS valve cover?....I'm considering this on my Catch Can setup.

 

[Glenn M]

Why not convert to a permanent dynamic drain system, dont have to remember to drain that tiny container then. That assumes the engine has been built properly and has low leak down numbers.

I had a similar problem when the engine was used hard and fabricated this system along the lines of the originals. It worked a treat.

 

[Joel Heinke]

Do you have images or suggestions on plumbing the Wagner PCV into the LS valve cover?....I'm considering this on my Catch Can setup.

This is obviously a highly modified LS engine (Magneson supercharger, SOHC conversion, etc.) but I think the installation approach for the Wagner PCV is still applicable to a lesser modified LS.

The PCV is placed in the hose connecting the drivers side valve cover to the intake vacuum fitting just behind the throttle body. Given the LS ignition coils mounted on top of the valve cover and the covers to keep them hidden, I think a hose to hose connection on PCV is better than mounting it directly in the valve cover. If your coils are mounted somewhere other than valve cover, then putting PCV directly in valve cover may be better.

The PCV is held in a simple aluminum bracket situated on the EFI fuel rail bolt. The hose connecting valve cover to PCV is not visible but goes under the fuel rail and into the bottom of the PCV. I didn't find an oil separator necessary once I installed adequate baffling inside the custom SOHC cam cover. I'm guessing factory LS valve cover baffling will be adequate for most street driving situations but may not be for track use.

I hope this helps.

 

[Bill Kearley]

An old thread, but Have a look at all the DI engines out their with build up on the intakes !!!!!!
I wonder if I should direct the crank case crap to the good old fashion draft tube. Will it mess with an ECM ???

 

[Scott Davis]

Thanks for replies/photos!! Later saw they had an inline version for hose to hose on another page. Will go with that.

 

[Howard Jones]

Does anybody know what exactly is going on inside of these?

 

[Jean-Marc]

Its is empty, it just to allow the oil vapors to condensate and go back in the engine. The water va

 

[Jean-Marc]

The water vapor will be extracted through the pipe on top.

 

[Howard Jones]

So does the big box drain oil back into the valve cover? Drain holes, where are they/it located, size, how many? Baffles inside? Where? Pictures of the interior?