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Boat fluid prep is a step you simply can’t skip when getting your boat ready for storage during the off-season. Check out these four tips to prepare your boat’s fluids for long-term storage.

1. Flush And Drain

A clean boat is a happy boat — at least, from a coolant perspective. At the end of the season, it’s a good idea to flush out your boat’s cooling system, which means running fresh water through a raw water cooling system to make sure it’s as clean as possible. Outboard motors need a similar flush and drain process before being put away long term. Make sure the final fluid you run through is antifreeze so that it leaves behind an anti-corrosive film inside the cooling passages.

If you have a closed-loop cooling system and don’t see subzero temperatures where you live, you’re looking at a flush and top-up. But if winter’s chill is subzero, then you’ll want to add antifreeze into the cooling system and make sure it reaches every channel and hose inside the motor prior to putting it away.

2. Stabilize Your Fuel

Over a long enough period, typically between four and six months, gasoline tends to break down into its constituents, which means your fuel tank could fill up with a nasty goop during the storage period. Using a fuel stabilizer will chemically prevent this from happening. It’s as easy as dumping in a bottle of the stuff during your boat fluid prep and then switching the motor on for just a few minutes to circulate it through the entire system.

3. Fill The Tank

Gasoline stabilizer is great, but it only has the job of protecting your engine’s fuel delivery system. It might feel strange filling up the gas tank just before the boat sits for a few months, but making sure that the tank and lines are completely full dramatically reduces the damage that can be done by any condensation forming inside the system. Condensation leads to corrosion, and corrosion will quickly block your fuel filter, pump and carburetors/injectors. Fill up as the final step in your boat fluid prep and you can avoid this issue almost entirely.

4. Brand New Lubricants

The final step in dealing with your boat’s fluids is to drain the engine oil and any other lube —transmission fluid, gear lube, etc. — and then refill prior to storage. This removes any contaminants or moisture that may have collected inside during the summer season. Remember to drain from a warm motor to make sure the oils flow properly and quickly.

Whether you live in a region where the winters are harsh and cold, or temperate and mild, proper preparation of the fluids in your boat will dramatically extend its life, and also help to prevent damage to important components.

Check out all the marine & boat products available on NAPA Online or trust one of our 16,000 NAPA AutoCare locations for routine maintenance and repairs. For more information on boat fluid prep, chat with a knowledgeable expert at your local NAPA AUTO PARTS store.

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