I thought i had an oil leak there, ended up being the rocker cover gasket which wouldnt seal on the crack where the timing case meets the head and the oil just ran down there. a bit of RTV silicone fixed that. might be worth a look?
I'm reviving an old thread here and probably going to open a whole new can of worms but I've found this which i thought a few people may be interested in.
http://www.baileysdiesel.com/on-highway/truth-adding-two-stroke-oil-diesel-modern-common-rail-engines/
I've had mine fitted for a couple years now also, no problems at all. One little thing i did was glued some rubber around the aluminium pipe where it goes past the radiator as it was rubbing a bit. I do have to take the pipes off when i want to get to the air and oil filters but its not hassle.
In my experience, aftermarket rocker cover gaskets are crap. i went through 2 in about 3 months, bought a genuine one and no troubles since. I got mine from Ebay it was about $40
Heres a link...
39nm? no way. If the last step in the torque specs is to tighten it a certain amount of degrees then it wont need re checking as they are torque to yield. Specs should come with the new gasket.
Best bet would be to get hold of a pressure tester and test it while the engine is cold, i had a little hose that would drip only after the car had sat for a while and cooled right down.
yeah thats all we used, i think the cheap hole saw just got blunt and it burnt the paint a little, not that you can notice it with the snorkel on there. Dont forget to paint inside any holes you drill to avoid rust as well.