I have a 87 Wellcraft St. Tropaz that has 2 Mercruiser 5.7 Stern Drives. The motors have a half enclosed cooling system. Last fall I removed the boat from the water and ran 6 gallons of Pink antifreeze through the intake hose by running the motor and pouring the antifreeze in the hose that attaches to the strainer basket. then I checked the antifeee in the cooling system. it looked good and tested good.
This spring I went to change the oil and it looked milky (bad news) the starboard motor (other looked fine). The oil I drained settled and the bottom on the jug was all pink antifreeze. After scratching my head for an hour or so. i asked the boat shop where my boat is stored. They said check the oil cooler. I looked and no oil cooler just a transmission cooler. the green Antifreeze is fine and it is full to the correct amount. I started the motor with a hose in the water intake and it ran just fine Pink antifreeze came out if the exhaust when I first started it as expected. Driving the boat last fall did not get any water in the oil I checked oil in both motors when we pulled it from the water (not milky). The motor does have an exhaust leak that is noticeable by sound and fumes in the boat on one of the exhaust manafolds Gaskets have been ordered. Any help appreciated.
This spring I went to change the oil and it looked milky (bad news) the starboard motor (other looked fine). The oil I drained settled and the bottom on the jug was all pink antifreeze. After scratching my head for an hour or so. i asked the boat shop where my boat is stored. They said check the oil cooler. I looked and no oil cooler just a transmission cooler. the green Antifreeze is fine and it is full to the correct amount. I started the motor with a hose in the water intake and it ran just fine Pink antifreeze came out if the exhaust when I first started it as expected. Driving the boat last fall did not get any water in the oil I checked oil in both motors when we pulled it from the water (not milky). The motor does have an exhaust leak that is noticeable by sound and fumes in the boat on one of the exhaust manafolds Gaskets have been ordered. Any help appreciated.