Answer
Dec 11, 2024 - 12:53 PM
Let me start off by saying that I have never personally worked on that exact engine, but the process is always pretty much the same.
Here's how I would do it:
First, stabilize the fuel in the tank by adding a marine-grade fuel stabilizer and running the engine for about 10-15 minutes. This ensures the treated fuel circulates through the system and prevents fuel breakdown over the winter.
Next, focus on the water drainage. Since your cooling system is closed, only the raw-water side of the system needs draining. Locate the drain plugs on the exhaust manifolds, engine block, and other components such as the power steering cooler or raw water pump. Remove these plugs to allow water to drain completely. Refer to your manual for the specific locations of the plugs on your engine.
After draining, flush the raw-water cooling system with fresh water. If your boat is on a trailer, connect water muffs to the lower unit and run the engine at idle while flushing. Ensure water flows freely out of all drain points.
With the water drained, replace the plugs and introduce non-toxic marine antifreeze into the raw water side. This protects against any residual water that might be left behind. You can use a funnel or a specialized antifreeze kit for this step.
Finally, fog the engine by spraying fogging oil into the carburetor intake or spark plug holes while turning the engine over briefly. This prevents corrosion inside the cylinders.
But that's just me, so you might want to make sure you follow the exact winterization procedure recommended by the manufacturer found in the repair manual.
Better safe than sorry.
