Contessa 26 Tech Notes

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Winterizing for Very Chilly Conditions (like below Zero degrees F)

by S. M. Hall.

Winterizing a boat gets a bit complicated when you live in an area where you can expect long periods of below freezing winter temperatures. Here are some tips and procedures for getting your boat ready for her winter snooze and then a no-surprises wake-up in the spring.

Water System: Drain the water tank somehow. You can rig a siphon or pump it out through the sink and let it drain over the side. Then pour in a gallon of non-toxic antifreeze into the empty tank and pump it into the sink until you see the color change. This will prevent freezing of the lines to the sink and damage to the pump itself. Do the same with the head. Do you have a sewage holding tank? If so, have it pumped out and slobber in some more non-tox.

Bilge and Bilge Pumps: Get as much water out of the bilge as possible. If you don’t have a bilge drain use the old sponge-on-a-rope trick or anything else that works. Replace the bilge drain plug and pour in a gallon of non-toxic stuff and run the electric bilge pump and operate the fixed manual bilge pump (if you also have that). The antifreeze is cheaper than replacing pumps. Once the pumps are squared away, open the bilge drain. Disregard this step if your boat does not have a drain.

The Engine will need: (in this order)

1. The fuel tank topped off and fuel stabilizer added. Stir it up if you can. It’s also a good time to drain off any water that may have collected in the fuel filter sediment bowl…if you have one.
2. The oil and oil filter can be changed after the engine has been run long enough to come up to temperature. There is a certain amount of condensation produced and some acids formed when the engine is running. Changing the oil gets rid of the moisture and any corrosive materials. You’ll need an oil pump with its suction hose small enough to fit into the dipstick hole. These are available from marine supply stores. Try to get it as deep into the oil as possible. This doesn’t remove all of the old oil, but it will get most of it.
3. Save checking the condition of the zincs until spring.
4. If you don’t know when the fuel filters were last changed, this is a good time to do that. If you don’t know how to change them and then “bleed” the fuel system, this is a good time to learn. With the new oil and filters installed, and the fuel system bled, run the engine again for a while to get the new oil through everything. Then connect the raw water intake hose to a bucket of non-toxic antifreeze and keep feeding it until you see color coming out the exhaust. Shut down the engine and wish the little darling a good winter’s nap.
5. But before she snoozes off, slacken the alternator and water pump vee belts and then give her a good wipe-down with some sort of light anti-rust oil. Don’t forget the shift linkage and the shifter. Everybody swears by WD-40. I don’t like the stuff by itself and always use a mixture of WD-40 and Marvel Mystery Oil. Why Mystery Oil? Who knows! When I was a kid, in somewhat prehistoric times, I was never without a can of it and used it everywhere. From bicycles to BB guns, it was the cookie. Strange habits are hard to break.

Mast and Rigging: There seems to be a trend today for leaving the mast stepped with its wind instrument sending units whirling away. It probably costs a few dollars less, but in my opinion, it’s asking for trouble that far exceeds any financial benefits. Freezing rain and snow gets into everything including the mast interior where it slithers down into the boat (if keel stepped) or onto the deck (if deck stepped with drain holes). It’s almost impossible to create a seal where the mast goes through the winter cover and therefore more water is allowed through to the deck. . Water penetration into even the best swaged wire terminals and Norseman type fittings can cause a lot of damage due to repeated freezing and thawing. Those somewhat expensive whirling gizzies don’t have much of a chance if winter gales come your way. Then there’s the business of rigging loads. Since the hull, when ashore resting on its keel, takes a somewhat different shape than it had when afloat, the rigging will also be differently loaded. It is my opinion that this is not a predictable situation and the combination of winter temperatures and winds from many directions may fatigue materials and degrading hardware and hull structures. Leaving the mast stepped may save a few bucks this year but is not an intelligent choice for the long term.

It’s best to get the mast off the boat where it doesn’t belong and get it ready for what’s coming. Good boatyards either store masts inside or on a yard rack that is totally covered with shrink-wrap. If you’ve dragged your boat home, you can even do a better job than the yards. One obsessive skipper that I know removes all his rigging (both standing and running), individually labels each, and hangs them up in his cellar. Initially I thought that this was one of his many overkills, but since the name of the game is common sense, he’s got a good practice here. This method allows you to individually inspect each piece and then to apply some sort of lubricant/corrosion inhibitor that can do nothing but good. The mast is then stored outside on horses (not the live kind) and wrapped with polyfilm. In the spring, you assemble everything using new cotter pins while keeping an eye on everything. Although time consuming, it sure makes sense.

Batteries and Electronics: Charge the batteries and store them inside where the temp is above 30 deg F. No magic here. I once worked at a gas station and my boss told me to never set a battery on a concrete floor because the mass of the concrete did something wild and wooly that would quickly degrade the battery. I’ve heard that this is an “old wives tale” that has no factual/scientific basis at all. I have never reacted well to facts that are in conflict with a perfectly good myth. I therefore store my batteries on a 2” piece of Styrofoam that insulates them from the basement floor. All electronics should be stored in a warm dry place. The fluctuations of temperature and humidity can cause condensation damage to certain components and degrading of printed circuit boards. Although most pc boards for marine use are coated with a moisture seal, in high volume products this sealing may not be of the best quality. It’s wize to keep the gear cozy and dry.

Winter Cover: Commonly, there are only two choices here – a tarp over a frame or shrink-wrap. I don’t believe in shrink-wrap and, since you’re properly storing your mast, don’t even think of using it for a ridgepole. There are enough relatively sharp edges on a mast to ruin the best tarp when the snow piles up. The common “blue” poly tarp is a poor choice. Material thickness is only about .003” and I’ve never gotten more than two years use out of one of these $30 cheapies. For about $70 you can get a “farm” quality tarp made from .008” material. The one I have now has been used for three years. This should be its last. The frame itself can be built from scrap wood or 1”x 3” strapping lumber. The only consideration here is to make the ridgepole high enough to let even wet snow slide off. To protect the tarp from any sharp edges, get a roll of “sill-seal” foam strip from your local building supplier and staple it where needed. Tying down the cover is not rocket science. Leave the ends open for ventilation and don’t fasten any of the hold-down lines to your jack stands – tie them from side to side passing under the hull. The whole covering routine shouldn’t take more than an afternoon unless you make it a social event.

Back to shrink-wrap. On the positive side, it’s relatively cheap and creates a snug fitting cover that keeps just about everything out. It’s also a slippery material that sheds snow and ice like a duck sheds water. You also don’t have to build a frame, own your own tarp, or spend a day putting it all together. Somebody else does all that in a quarter of the time. Unfortunately, there isn’t much more to say that would be positive. While it keeps everything out (except hornets), it also keeps everything in. I’ve worked on shrink wrapped boats on cold sunny days and have always been amazed at how warm it can get on deck. Sounds great doesn’t it – until the sun goes down and it cools off quickly. Day after sunny day this thermal cycling goes on and my gut feel is that it isn’t doing anything much good. Moisture retention is another issue even when the installers put on those hooded vents. During the damp days of early spring it’s most noticeable and sometimes the condensation drips from the inner surface. I’ve seen few installations that have provided the level of ventilation that comes naturally with a tarp over a frame. Tarps “pump” when the wind blows. It’s the nature of the beast and this pumping gets a lot of air moving. This lack of ventilation may have some serious consequences that have not been noticed before now. Several marine surveyors have recently discovered substantial side shell blistering on hulls that have been shrink wrapped all the way down to the waterline. Since these boats were left wrapped for a year or more, this may not be an issue for seasonal storage, but I believe that the conditions for blistering exist when any covering traps moisture. Since blistering is a progressive thing, it may not be wise to even consider poorly ventilated shrink wrapping for seasonal storage. If you’re stuck on shrink wrapping, have the installer place blocks of foam or another suitable material between the lower “belt” and the hull. Use enough of these blocks and the hooded vents to insure that a good volume of air will get in and out. And don’t wrap much below the shear line. I still think that the old tarp is the best choice.

Jack Stand maintenance: You don’t set’em and forget’em. All the weight of the boat is on the blocks under the keel and large fluctuations in temperature may cause movement in the ground that everything is resting upon. If the blocks sink a bit, the stands start taking the load. I’ve seen hulls “dimpled” by this. Generally, if not left too long, the dimples pop out but sometimes they don’t. If the ground under the keel blocks heaves upwards, the jack stands can’t do their job and the boat sways side to side when the winds blows. Check them regularly but mostly when there has been a major change in temperature like after the first deep frost and after those few warm days that trick you into thinking that spring is just around the corner (when, in reality, it’s way down the pike).

Note: I’ve pointed out, here and there, that certain statements are clearly my opinion. In reality, everything here is my opinion and you will, no doubt, find many other opinionated old blabbers with different views than mine. Since resigning from the Flat Earth Society, I have, however, become more realistic in my approaches to boat maintenance and welcome any comments, corrections, and additions.

29 OCT 2002

S. M. Hall