Toyota 1e engine

We have already changed 3 times pistons, rings, rectified block and the valves with their seals but at 1000 kmts start spending oil and produces blue smoke escape. Like workshop manual and/or tips. The vehicle is Toyota Stalet 1989, 1000 cc, motor 1-E and EP-70 chassis.
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Hopefully someone can give some opinion ...

Hi Gustavotene.
You write down that you have done the repair with the same result three times, if the rings are fine and sitting perfectly in the cylinders, the compression pressure is normal, correct valves and seals, but the fault is in the same time of work. You can think of a low oil pressure, or a poor diet to the pistons, they resist until that working time because that is their resistance, the fact that it is always in that period, is what makes me suspect. Luck.
Miguel

Friendly the 2E engine happens the same thing is completed and suddenly appears, what what was to improve and sust Like the seals and gias of valve the rest does not matter

I do not forget in the specific case of the 1E engine but the 2e brings within the cylinder block a bolt, with a face of doing nothing, which generally takes it out and never puts this bolt brings inside the head where a kind of spring is housed that regulates in one part the precion of the oil.