Re: Winterization for 2005 175 Balyliner, 3.0 l Mercruser
If you live in Edmonton, you have no time to waste to get this done. Aren't you getting freezing temps at night already? It doesn't take much frost to crack the block or break the leg.
Do you have a manual for the Mercruiser? It should tell you exactly what procedure to follow to winterize the unit.
The main point is to get all the water out of the block, leg, and all the parts in between. My Mercruiser is a 4.3 L V6, so it will vary somewhat from yours.
You need to remove whatever plug(s) are on the side of the block (look for a brass drain plug down low just above the oil pan) to drain the water. You may only have one plug - the V6 has two. Poke a wire into the hole to make sure no crud is blocking the water from draining. Also disconnect all cooling hoses and drain them well. Lower the leg all the way down and drain it well. Then replace the drain plug and reconnect the hoses. Then pour some non-toxic RV antifreeze rated for -50 into the cooling system. Hit starter for a few seconds (make sure engine does not start) to circulate anti-freeze through the water pump.
Also remember to drain the oil out of the leg and replace with fresh gear oil. Water in the gear oil can break the leg.
Hope this helps.