the only way your lower unit will crack from freezing is if its completely full of water. when you fill your lower unit with oil you only fill it until it comes out the top drain. that leaves you about a quarter of the space in the lower unit filled with air. they do this so when the lower unit oil gets hot it has room to expand. so if you have water in your lower unit mixed with the oil it will only freeze and expand and when it gets warm it will defrost. and if you do have water in your lower unit you shouldnt be running it anyway because you need to have it resealed and if you have been running it knowing you have a broken seal then you really dont care about your motor and shouldnt worry about it freezing anyway.
|