J series-Breather Setup

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ChasingSand

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For the turbo Guys, can you post pictures of your pcv/breather setups? Currently running a -10 of each valve cover but am concerned it’s large enough. 

 
I've got 3 -12 lines. 1 line is low enough and allows the breather box to drain back into the engine.

I had a smaller breather box before and only 1 breather line. I was blowing oil out of the engine and was blowing oil past seals and dipstick. I have eliminated all breather issues with this setup. 

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And I have removed the factory PVC and plugged the lines

 
Isn't boost boost?  Independent of turbo or SC?

Anyway, I have 2 -10 lines on my setup.  13lbs of boost.

The return line replaced the factory PVC location.

 
JM PRO said:
I've got 3 -12 lines. 1 line is low enough and allows the breather box to drain back into the engine.

I had a smaller breather box before and only 1 breather line. I was blowing oil out of the engine and was blowing oil past seals and dipstick. I have eliminated all breather issues with this setup. 

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This is extremely helpful! My turbo is still leaking and now also the rear main is leaking. Going to switch to a -12 setup.

 
lincster said:
Isn't boost boost?  Independent of turbo or SC?

Anyway, I have 2 -10 lines on my setup.  13lbs of boost.

The return line replaced the factory PVC location.
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It is a turbo setup. Are your valve covers baffled internally? I am thinking my baffles might be causing restriction.

 
ChasingSand said:
It is a turbo setup. Are your valve covers baffled internally? I am thinking my baffles might be causing restriction.
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I understand it is a turbo setup, my point was from a venting standpoint, shouldn't matter how boost is made, venting is still needed.

No, I have no baffles on my valve covers.

 
When i built my engine, I made a couple mistakes, I bought forged pistons in stock size then had a machine shop clean up or true the cylinder wall. (It had some taper). That made my pistons extremely loose in the cylinders. The manufacturer of the pistons said i was within spec  just will be loud when cold. I also made end ring gaps at ,022 and .024" for my top 2 rings. With the combo of sloppy pistons and large ring gap I get a ton of crank case pressure now.

I removed internal baffles on valve covers, removed and plugged stock PVC and run 3 -12 lines from valve covers and I built a breather box that has an internal splash plate and a missive 2" base opening air cleaner. I now have zero issues with oil wanting to escape engine.

Side note- when the motor was bone stock straight from the junkyard, running the same amount of boost, a simple breather box with 1 breather line worked perfectly fine.

 
JM PRO said:
When i built my engine, I made a couple mistakes, I bought forged pistons in stock size then had a machine shop clean up or true the cylinder wall. (It had some taper). That made my pistons extremely loose in the cylinders. The manufacturer of the pistons said i was within spec  just will be loud when cold. I also made end ring gaps at ,022 and .024" for my top 2 rings. With the combo of sloppy pistons and large ring gap I get a ton of crank case pressure now.

I removed internal baffles on valve covers, removed and plugged stock PVC and run 3 -12 lines from valve covers and I built a breather box that has an internal splash plate and a missive 2" base opening air cleaner. I now have zero issues with oil wanting to escape engine.

Side note- when the motor was bone stock straight from the junkyard, running the same amount of boost, a simple breather box with 1 breather line worked perfectly fine.
Click to expand...
I have the same problem! I do have some piston slap when cold but does go away pretty quickly once the car is warm. 

I kept my baffles but will be removing them before my next trip. This will probably explain why my turbo kept leaking past the seals and I also now have a rear main seal leak.

Also, The lines that ran from my valve covers to catch cans had low spots in them and condensation was building up and I am wondering if that also was causing blockage as well.

 
Breather lines can't have any droop in them. Oil will get caught there and restrict air flow. And u need at least one line that drains back to the engine.

Not sure if your crank case pressure issue is related to the turbo leaking. The seals in the turbo are holding oil back, not crank case pressure. But I could be wrong.

 
JM PRO said:
When i built my engine, I made a couple mistakes, I bought forged pistons in stock size then had a machine shop clean up or true the cylinder wall. (It had some taper). That made my pistons extremely loose in the cylinders. The manufacturer of the pistons said i was within spec  just will be loud when cold. I also made end ring gaps at ,022 and .024" for my top 2 rings. With the combo of sloppy pistons and large ring gap I get a ton of crank case pressure now.

I removed internal baffles on valve covers, removed and plugged stock PVC and run 3 -12 lines from valve covers and I built a breather box that has an internal splash plate and a missive 2" base opening air cleaner. I now have zero issues with oil wanting to escape engine.

Side note- when the motor was bone stock straight from the junkyard, running the same amount of boost, a simple breather box with 1 breather line worked perfectly fine.
Click to expand...
Good thing you explained.  You for sure have something "different" than most do.  So that makes sense with your setup.

 
JM PRO said:
I've got 3 -12 lines. 1 line is low enough and allows the breather box to drain back into the engine.

I had a smaller breather box before and only 1 breather line. I was blowing oil out of the engine and was blowing oil past seals and dipstick. I have eliminated all breather issues with this setup. 

View attachment 95145

View attachment 95146

View attachment 95147

View attachment 95148
Click to expand...
Thanks for posting some very good pictures. What is the diameter and height of your breather can? Does the return line go into the bottom of the valve cover? How many miles were on the motor you had the cylinders cleaned up? 

 
Is there any speculation about the amount of boost and the size of the lines? IE up to W PSI of boost 10AN lines are good and X-Y PSI 12AN lines are adequate? Over Z PSI you must have an ??AN line?

 
I made the breather can out of 3" tubing. Believe it is roughly 6" tall. The 3rd lowest return line goes to the factory breather location on the flywheel side of the valve cover. The engine was beat and old. My guess 150K - 250K in miles. I didn't bother looking it up.

Surprising thing is I have had the engine apart several times now and I have not replaced the stock main bearings. They look great and I didn't see a reason to do the appropriate machining to change out. I have replaced the rod bearings when the forged rods went in.

 
Here is the backside of the valve cover. With a rear engine, it traps oil up by the vent port and does not allow it to easily return to the engine. I removed them from both valve covers.

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