Is anybody can help me to diagnose about this engine problem. I remomed the cylinder for testing for crack but there's no problem. again I put it back, installed new head gasket and new intake manifold gasket during a test for 30 min. using waterhose it seems that everything is okey but when i test run in the lake for 2 hours i found out the water mix into the oil. I'm planning to replace the 20-yr. old manifold before I will suspect the block has crack. Any recomendation is highly appreciated. Thank you