I have a 2001 Glastron with a 4.3 Mercruiser engine. The engine did not get drained and winterized properly last fall. I found a soft plug that was popped out of the left side of the motor. I replaced the plug, hooked the water muff up to the outdrive and started the engine and let it run for 5-10 minutes at different RPM's. It ran fine, good and smooth, got it warmed up and shut it off. I pulled the dipstick, but the oil looked good and at the correct level. When I drained the oil, it was milky like there was water getting into the oil. It also smelled gassy. Do I have a cracked block? Does the motor run that good if it is a craced block? Could something else be cracked? If anyone has had any experience or problem with this, any advice would be appreciated. Thanks