Chevrolet Corsa Motor Isuzu 1.7

It is the engine and you lose oil. By the distribution plate where the oil pump is.

Tip, always between metals some type of joint or sealant (the metal is never perfect and there is always some pore, and the withdrawal changing it.

Another advice, when an engine is opened all precaution is little, always seal between metals and change everything that carries rubber, seals, toricas etc etc, because since it is open you cure yourself into health.

The retain is new. Thank you

Good Roberto. I had a similar case and then it was that the crankshaft axial caps had a lot of lateral slack.
With a detachable or large screwdriver, check that slaughter on the crankshaft pulley to see if it moves a lot in and out.
Have luck ...