Toyota 1e engine

We've already replaced the pistons, rings, and had the block resurfaced and the valves and their seals replaced three times, but after 1000 km it starts consuming oil and producing blue smoke from the exhaust. I need a workshop manual and/or advice. The vehicle is a 1989 Toyota Stalet, 1000 cc, 1-E engine and EP-70 chassis.
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Hopefully someone can offer some opinion...

Hi Gustavoteno.
You mentioned that you've done the repair three times with the same result. The rings are fine and seating perfectly in the cylinders, the compression pressure is normal, and the valves and seals are correct, but the problem persists at the same operating time. It could be low oil pressure or insufficient oil supply to the pistons. They only last up to that operating time because that's their maximum capacity. The fact that it always happens within that timeframe is what makes me suspect it. Good luck.
Miguel

My friend, the 2E engine has the same problem. They get completely rebuilt and then suddenly it happens. What I did was improve and increase the viscosity of the oil, and they last longer. Of course, for this, I also ran it cooler than usual to avoid overheating. This only applies if you've had the cylinders of the block honed and not just replaced the rings. Check that the parts aren't aftermarket, especially the rings, pistons, seals, and valve guides. The rest doesn't matter

Oh, I almost forgot, I don't know about the specific case of the 1e engine, but the 2e has a bolt inside the cylinder block, which looks like it doesn't do anything, and it's usually taken out and never put back in. This bolt has a kind of spring inside the cavity that regulates the oil pressure in part.