How to Run Your Outboard Out of Water to Prevent Freeze Damage
Protecting Your Outboard in Winter: A Guide to Freeze Prevention
As the boating season winds down, it’s time to prepare your outboard motor for the cold months ahead. The single biggest threat to your engine during the off-season is freezing temperatures. When water freezes, it expands by about 9%. If it’s trapped inside your motor’s cooling passages, that expansion can generate enough force to crack the engine block. This is a catastrophic and often unfixable failure.
Proper winterization is the only way to make sure your motor runs next season. This means knowing how to run an outboard motor out of water safely, which lets you circulate protective fluids and ensure the cooling system is fully drained before storage.
The #1 Goal of Winterization: Get the Water Out
The core principle of freeze prevention is simple: remove every drop of water from the engine. While modern outboards are designed to self-drain, following a few key steps in the fall guarantees no water gets trapped inside where it can freeze and cause damage.
A Step-by-Step Guide to Winter Protection
Follow these steps to ensure your outboard is protected and ready for those warmer months.
Step 1: Stabilize the Fuel System
Before your final run, treat the fuel in your tank with a quality fuel stabilizer. This prevents the gasoline from breaking down, gumming up, and clogging your fuel system during storage. Follow the instructions on the stabilizer bottle for the correct ratio.
Step 2: Perform the Final Run on Land
To circulate the stabilized fuel and prepare the engine for its long sleep, you need to run it one last time. This is where knowing how to run an outboard motor out of water is essential.
- Connect a Water Supply: Securely attach a motor flusher to the water intakes on the lower unit. Connect a garden hose to the flusher.
- Turn Water on First: Turn the hose on to a strong, steady flow. You must see water flowing to the motor before you start it.
- Start the Engine: Let the engine run at a low idle for 5-10 minutes. This circulates the stabilized fuel through the entire system.
- Fog the Engine: While the engine is running, spray fogging oil directly into the air intake according to the product’s directions. You’ll see thick, white smoke from the exhaust. This process coats the internal engine components with a protective layer of oil to prevent rust and corrosion.
- Shut the Engine Off: Once the engine begins to bog down from the fogging oil, shut it off immediately.
- Turn Water Off Last: Disconnect the water supply.
Step 3: Drain the Cooling System Completely
This is the most critical step for freeze prevention. Once the final run is complete, you must ensure all water drains out.
- Store the Motor Vertically: Trim the motor all the way down to the vertical position. Whether it’s on your boat’s transom or on an engine stand, this is the only position that lets gravity fully drain the cooling passages. Any other angle could trap water inside.
Step 4: Final Protective Measures
- Change the Gear Lube: This removes any old, broken-down lube and, more importantly, lets you check for water intrusion. A milky, white appearance in the old lube indicates a bad seal, which should be repaired before storage.
- Protect the Battery: Disconnect the battery and store it in a cool, dry place, preferably on a trickle charger to maintain its health.
- Clean and Cover: Clean the exterior of the motor and apply a coat of wax. A breathable cover protects it from dust, debris, and moisture.
Protecting your outboard from the freezing temperatures of winter is a simple process that pays huge dividends. By following these steps and understanding how to run an outboard motor out of water as part of your winterization routine, you can prevent costly damage and ensure a quick, trouble-free start to your next boating season.
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