hi, I had a leeking head gasket on my 6G72 engine, so I stripped it and removed the heads.
I found that water was leeking in to # 4 cylinder, the only signs I had earlier was that the colant was dissapearing without any sign of a leek.
There was no sign of water in the oil.
So I had the heads serviced, valves reseated, the lash adjusters replaced, head shaved, and checked.
I reasembled, the engine with new gaskets and as described in repair manual.
I started the engine, it ran but it sounded noisy, so after 1 minute, I turned it off and drained the new oil I had just put in, and found that it was a light tan color, a lot of water has mix with it.
I stripped the engine again, replace the haed gaskets with genuine ones, and reasembled the engine.
The same thing happened again, I cannot find where the or how the water is entering the oil system.
I checked the compression in each cylinder, and they were all around 120.
I am baffled.
Can anyone help?

you may have an internal crack in the block
between a water jacket and an oil gallery

did you check the top of the block for warpage with a straight edge

max warpage may be only 2 mm

a straight edge and a feeler guage

if the feeler guage goes under the straight edge then the block needed refacing also and a pressure test