I don't think we will ever have a big winter problem on the Gulf Coast. We don't really get extremely cold in the Gulf Coast area, but we do have cold snaps. Here are some tips to winterize your boat.
Your first step in winterizing should be to make a checklist of all items that need to be accomplished. Check the owner's manual of both your boat and motor for the manufacturer's recommendations on winterization. If you are a new boat owner, perhaps you should employ the assistance of a friend with experience in winterizing or hire a professional to do the job.
The fix here is to vent your boat cover for good airflow to minimize trapped moisture for small boats. But even big boats that are locked up for the winter, more than one boat owner has unzipped his boat in the spring only to find the interior looking like a science project with mold and mildew everywhere. Mildew sprays are a big help, as are chemical dehumidifiers that pull excess moisture from the air.
Water is the enemy when it comes to fuel supply and storage systems on boats. That’s especially true if yours is a gasoline-powered boat with ethanol-blended fuel in the tank. Diesel fuel comes with its own set of challenges. Add in wide ranges of winter temperatures and condensation becomes a problem.
Clear, amber-colored lubricant means your gear-case seals are in good shape. Milky and sometimes lumpy oil means the seals need to be replaced. Tip: The time to do this is in the fall when marine mechanics are less busy and sometimes willing to offer special prices for winter work.
Now is a good time to change fuel filters as well, especially if you have a stand-alone water/fuel separator filter. Check your manufacturer’s recommended service intervals for onboard fuel filters on your inboard and/or outboard engines.
Change engine oil to eliminate moisture and prevent corrosion. If you don't, moisture can cause excessive wear, which can lead to loss of power, poor fuel economy and possible engine failure. Tip: Some mechanics change the oil both in the fall and at spring breakout on the theory that the engine oil needs to be changed at the end of the summer and after suffering the ravages of winter because moisture may again accumulate in the oil.
Treat your boat's fuel with a stabilizer. Pennzoil Fuel Stabilizer, PRI-G and Stabil are ideal products for this job. After adding it to the fuel, run the engine for 10 minutes or so to be sure stabilized fuel circulates throughout the engine. If you don't stabilize the fuel, carburetors and fuel injectors can be clogged with varnish deposits that ruin fuel systems.
Probably the worst thing you can do to your batteries is leaving them unattended and ignored in your boat all winter long. They should be on a trickle charge during this downtime, and if you don't have a solar charger or a plug at the boatyard and your boat isn't stored in the water the best place for your batteries is at home—either in the garage or basement—hooked up to a trickle charger. And don’t worry; Dr. Diehard says it’s perfectly fine to store today’s batteries on concrete.
Keep in mind that different battery types have different charging needs. For example, a conventional lead-acid battery has a much higher charging voltage tolerance than an absorbed glass matt (AGM) battery. Find out what’s best for your particular battery type and be sure to keep an appropriate trickle charger going on your batteries all winter.
If you need a more comprehensive explanation of battery maintenance needs—for all seasons and conditions—be sure to watch this Basic Boat Battery Check Up and Maintenance video.
After going through all these systems and processes, are we finally ready to put Mom's Mink to bed for the winter? We're close. Here are a few final winterizing tips to finish the job: