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12J ex mod valve cover leak

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The newly rebuilt engine has been leaking too much oil, even for a Land Rover : ). The engine is a 12J from an ex MOD Defender.

I thought that it might be the rear crankshaft seal. I cleaned off the engine and disconnected the crankcase ventilation hose from the oil filler cap. I let the engine warm up and tightened up the three nuts holding the valve cover, using copper or Al crush washers. After ~20 minutes of idling, no leaks!

I reattached the hoses and went for a 10 minute drive and was met with the leakage pictured on return.

I checked the hoses and there are no blockages and the cyclone breather was ok when I put it back on the engine after the rebuild. Could the round valve (err1468) that sits above the  cyclone breather be too stiff to open sufficiently to let air go to the inlet manifold? It does open now. 

(I have attached a pdf of the system on my engine - the link is above the photo)

Would it be better/a solution to run the hose from the oil filler cap to a catch can, and from there to the air intake, bypassing the cyclone breather? 

Do the ERR1468 valves fail?

Maybe I could substitute in this: http://www.ebay.ca/itm/Land-Rover-Defender-2-5-N-A-Cyclone-Engine-Oil-Breather-/201949618819?hash=item2f0522a283:m:msAZCYkL5CuSA8CNZ_4J-qg

Are these stud holes a common oil leak spot? maybe rubber o rings to further keep the oil inside?

Does the crankcase pressure subside as the engine wears in?

I thank the collective wisdom of this site and look forward to your advice!!



Crank Case ventilation 2.5na.pdf

Oil Leak Through Valve cover stud hole.jpg

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