had an impeller fail on me which caused engine to over heat , didnt notice any problem till the following year found water in oil . after the shock and illness i changed the oil 3 times to get water and white cream out . tryed to put stop leak in water jacket . it seemed to work ran the season without any problems than after running 2 or 3 times this season found more water in oil. was thinking about useing more stopleak but i think theres something warped or cracked .maybe a gasket dont where to start any idea
that can make it hard to find, you need to block off water TO the exhaust system, then drain the cooling system, and pressure check the block. Depending on which 4.3 you have ( and there is a bunch) it's probably a block or intake crack, slight possibility of a head crack.