It is hard to believe, but it is the first of September and I’m writing about winterizing! But the sad fact is that is, by the time you will be reading this it will be Octobder and you’ll be thinking of winterizing your boat.
Separating water and boats is no easy task. But when it comes to winterization, a major part of the effort is to do just that.
Most boats have some kind of fresh water system, whether it is a single tank and a manual faucet or a vast system with several tanks, electric pumps, multiple outlets and a water heater. But the principles are the same in each case: You need to get the water out and the antifreeze in.
Fail to do so and the residual water in your tanks and lines can freeze when the mercury drops, leaving them vulnerable to damage and leaks. For the same reason, bilges should be dried, the waste tank emptied and systems that use sea water should be drained and the thru-hulls closed.
The best way to ensure that all these steps get done is to develop a check list. Check lists have worked well for pilots and shuttle commanders for years—and there is no reason they won’t work for you. The list should note the systems that require attention; the amount of supplies (such as antifreeze) needed and as any special tools required to complete the task.
The first step in winterizing your water system is to get all the water you can out of the system. That means letting the pump run, with all the faucets open until nothing but air comes out. Because you are purging water lines, as well as the tanks, be sure to include all sinks, showers, washdowns and anything else that draws fresh water.
A special case is the water heater. The best strategy is to fit your boat with a bypass kit that will allow you to drain the water heater dry, and then skip the antifreeze. The reason is simple: if you forget to drain the antifreeze out of it in the spring and start up your heater, the smell and taste of cooked antifreeze will be with you for a long, long time.
The antifreeze of choice for this application is non-toxic propylene glycol, which is sold for marine or RV potable water systems. The antifreeze is USP or “food grade,” because it is used with drinking water. It is usually pink and has a rated slush point of -50 degrees. Under no circumstances should automotive or ethylene glycol antifreeze be used in a water system, because these products are toxic.
Pour your bottles of antifreeze into the empty water tanks through the same deck fill you use to add water. Don’t be tempted to dilute the antifreeze before adding it to your tank. It will mix with the residual water left in the system, and any further dilution will reduce the protection it provides.
You will not fill your tank (that would be expensive and unnecessary). Rather, the goal is to add enough to spread the antifreeze throughout your entire water system. The exact amount will be different on each vessel. When in doubt, buy more. You can always use it elsewhere on the boat, or hold it for the following season.
When the tanks contain enough antifreeze, start up the water pump with all of the faucets and outlets closed except the one furthest from the pump. Leave it on until pure antifreeze comes out of the outlet. Allow it to run long enough to flush all the fresh water out of the drain lines (all drains must be flushed with antifreeze or residual fresh water in the line can freeze.)
Once the antifreeze has come out of the outlet furthest away, close it off and open the next outlet and allow it to run. You want to work your way back through your water system until all faucets and outlets have antifreeze coming out of them and all drain lines are flushed.
Be thorough: everything that uses fresh water should be treated, including sinks, showers, washdown systems, windshield wipers, washing machines, ice makers and live wells. While the live well might look empty, there could still be water left in the lines and pumps that will cause problems.
The most important ancillary system is the toilet with its holding tank and associated hoses and valves. The holding tank should be pumped out and flushed several times with clean water, and then pumped as dry as you can get it. Add antifreeze to the toilet bowl, replacing all the water in the bowl and lines, and pump it through the system until it enters the holding tank. Depending on the amount of residual water, you may want to add a little more antifreeze to the holding tank. Pour a little antifreeze down the pump-out fitting to be safe.
Another vital system is the air conditioner. Most air conditioners use raw water to cool the refrigerant, and that cooling circuit also needs to be winterized with antifreeze. One way to do this is to add antifreeze to the water strainer, if it has the proper fitting to do so. If not, close the seacock, disconnect the intake hose and run it to a bucket filled with antifreeze. When you run the air conditioner, the line will suck up antifreeze instead of sea water. The antifreeze must go through the entire cooling system and out the discharge to fully winterize the system.
If your ice box has a drain line, you will need to flush that with antifreeze too, as well as any cockpit or deck drains. Depending on the angle the boat is stored, rain water or snow melt could collect in those lines and freeze. Check them regularly during the course of the winter and add antifreeze if necessary. Don’t assume your cover or shrink wrap will not leak.
BILGES AND BILGE PUMPS
If there are areas on the boat that regularly collect water, such as a lazarette, anchor locker, drain or bilge area, you will want to dry them out thoroughly using a pump, rags or paper towels. Generic disposable diapers are another great tool; just immerse them and come back a few minutes later to clean up. If you don’t think these areas will stay dry, you can add antifreeze and check them periodically throughout the winter—especially after rain and snow.
One area commonly overlooked is the bilge pump system. Many times there is residual water left in the discharge line and in the bilge itself. Run antifreeze through these pumps by pouring some into the bilge and running the pumps. Don’t forget the permanently installed manual pumps, either.
Whether or not you leave antifreeze in your bilge depends on your experience with the boat. If the bilge tends to stay dry through the winter, pump the bilge dry, towel it and be done. If, however, you think it will collect water, leave antifreeze in the bilge to inhibit freezing.