oil in cooling water
 

I have a 2000 2.5td voyager, a few weeks ago i the header tank was full of engine oil and overflowing through the over flow hose. There was only 3 liters left in the sump. Engine runs fine, no water in engine oil, i have pressure tested the oil cooler with air pressure 4-5 bar with no signs of leakage ( i even warmed up the oil cooler to 90 degrees) I removed the cooling water manifold that is mounted on top of the cylinder heads, removed the serpentine belt and started the motor with water filled up to the openings on the heads. within a few seconds small oil drops came up through the cooling water opening on cyl 1. the black oil accumulated at the opening floating on top of the water but only in cyl 1. as soon as i turned of the engine more oil came out and even through the openings of cyl #2, 3, and 4. within running the engine for maybe 3 minutes i lost at least 1 liter from the sump. I have now removed the heads but there is no obvious sign of leakage plus there are no oil channels between the block and the heads. only a feed pipe that lays on top of the heads lubricating the rockers and valves. those lube channels seem to be okay as well ( fluid leak test done)
What could be wrong?? does anyone know what to do?
I appreciate any help, Thanks Emil Vienna Austria

I guess it would be better if you go to your mechanic, I'm pretty sure they knows best.:D Anyway, I read from an article that certain things such as oil and water, Klingons and Tribbles, Michael Bay and films, and so on, are never intended to combine. Another is General Motors and Ford, but the two businesses have matched up to joint-develop nine- and 10-speed transmissions. In addition, you may try to check out this article here for more tips on car care: 2010 Ford Pickup Ranger Spokane WA