Looking for help on a 4.3 L Mercruiser?
I started up my boat in the spring and it started up fine. I have a 2005 4.3L Mercruiser. I put it in the water and boated for about 5-10 minutes and then it stalled. I opened up the hood and saw that there was milky oil coming out of the valve cover
You are getting water in the crankase, which probably indicates a cracked block, a leak-down test may or may not confirm this. When you ran your boat up to operating temp, the crack expanded, allowing more water in. These cracks are impossible to see

