Oil in the escape

Good morning, to everyone, I present myself:
my name is Antonio and I live in an isolated area of ​​the island of Mindanao in the Philippines.
We have a van with a Nissan TD 2.7 engine in the family.
The fact is that a week ago as we made smoke and oil for the escape, we went to the Davao capital to try to repair the engine, the first thing we checked was the turbo, they changed the two antifriction metal bearings and a kind of washers that looked like some type of very fine stamps or seals, and they told us it was fine.
Then pistons were disassembled, the hoops were changed and the cylinder head was changed, for one of scrapping but proven and with the stamps of the new valves.
The fact is that when I returned home (290 km) after two hours of road without putting cane again, smoke and oil came back through the escape.
As we could not return to the capital, we decided to put hand at home, disassembled turbo and well (in sight) we disassembled and well (in sight) when taking out the pistons we observe that the hoops were put to the good of God so we decided to blame the bad assembly of the hoops, we clean everything well with gasoline and remembered everything with the adjustments of the manual for squeezes and with the 120º.
Once everything is mounted, we start perfectly and obevo that it does not make any smoke, combustion is perfect, but it continues to spit oil through the escape, almost nothing if we compare it to the principle of the fault, but some spray dropper continues to release.
As I do not know what to do, we decided to leave it as this, work with the van observing whether the problem increases and waiting to see if the Holy Spirit enlightens us, since our wisdom is exhausted, and we no longer have an idea of ​​where to touch, and we consider that in this case and for the moment I better not touch anything.
I would appreciate any guidance on the matter very much
(better if the orientation does not mean use of micrometers or sophisticated things) the most sophisticated we have is a dynamometric wrench feet x pounds and a normal caliber.
Thank you very much if someone can make me a hand.
Also clarify that I am the theoretical, that those who have better hands that I are my family here.

Hi Colisber, along with greeting you, I congratulate your description. My recommendation, observing that you did everything right, is to wait, watching if it consumes oil. My opinion is that if there is an incipient problem in your engine, using it with caution this should be more clearly and thus be able to perform the diagnosis. The other is that this OK and the oil probate of accumulations in the exhaust tube, especially noise silencer, if it is so we will use everything will be fine, if not or previous. If you do not observe excess oil consumption, the turbo is ok, and the engine has little strength, the injection pump can be behind, they also smoke blue as oil, but it is in late diesel in the engine, therefore not combustion correctly (slightly different characteristic smell of oil in combustion camera. I do not know if I explain well. I would not worry in excess. Greetings cordials. It was worth it

Hi Colisber, in accordance with the opinion of Fiat 147, there may be yet, oil residues in the escape, already burned, congratulating yourself for doing things well, (the segments in your position) .. and also giving my opinion, if you observed any line in some cylinder is a motivio of high oil consumption, also the slack in the valve guides, and observe if the intercoler is not filled with oil ... Part of all this, personally distrust that changing the ceramic seals of the turbo is anything, if this is not balancing later, it will end up as I tell you ... and more knowing how the segments mounted you, in any case I wish you luck and go "for good" and do not start to hear the famous "whistle" of the turbo. greetings!!!