How to Winterize Your Boat and Save Some $$$ (Because Boating is Expensive!)

September 5, 2022

Written by guest blogger Captain Fix-It

No expert here, just a jack of a few trades. Most everything I know was “taught” to me by my dad, posing lots of questions to those that traveled the road before me, reading a few magazines, or otherwise gained through enrollment at YouTube University. I do not pretend to have invented the wheel. ​ ​ For the most part, this stuff (boating maintenance) is not difficult, so if your boatyard (or wherever you store your boat) allows you to winterize and spring commission on your own, certainly consider it. It will save you a few bucks to throw at the marina for the bigger jobs or the ones you’re uncomfortable with. For me, that’s mostly everything electrical.

I do the following on a boat with twin 2008 gasoline 496 Mercruiser 8.1 Horizons and a Kohler generator (genny). For the future boat, I will need an MBA in Diesel Mechanics from the university mentioned above.​ ​ Create a spreadsheet/checklist that you can reuse and edit/add to from year to year. I’ve included some of my thoughts below to help better explain this checklist.

When changing the oil, oil filters, and fuel filters in the port and starboard engines, remember not to forget the genny! Considering if it’s time to change your impellers?

How are your manifolds? Do you know when they were last changed or at least inspected? If not, it will be a worthwhile investment in new gaskets to at least pull the riser off and inspect the manifolds by looking down inside them. My surveyor said that the replacement of the manifolds typically are not necessary until you started to gain temperature on the thermostat, or you could not hold your hand on the manifolds after they were up to temperature.

If what he says is true, then when I inspect mine this winter, they should be fine. However, there are some external spots on the outermost manifolds that look suspect so depending on how deep into the inspection I go, I may opt to replace and then not have to worry about them for at least five to seven years (by then, if my wife has her way, we’ll be onto a bigger boat). ​ ​ Next, get low and inspect your raw water intake lines. During this year’s winterization process I noticed that one hose had a crack forming and the other portions were going to fail (it was just a matter of time). I will replace those before the boat goes in the water in the spring. After I complete this job for the engines can you guess what I am going to do?! Check the same for the genny! ​ ​ Now, moving back to the winterization process. Flush and “pink” engine(s). Pink simply means to run “pink” antifreeze through whichever system you are working on until you see pink come out of the discharge outlet. If you are winterizing in even colder climates, you may refer to this as “purple” or whichever color your antifreeze is. You may find it helpful and save a few gallons of antifreeze to drain mufflers and vacuum out sea strainers of water and drop water from engines if capable. Doing so leads to less dilution of antifreeze.​ ​ Flush and pink the A/C. Pink the toilet with at least a half-gallon and send it to the holding tank.

Vacuum out and then pink your shower sump pump. ​ ​ Next, you’ll pink the freshwater system, but make sure you switch to the water system pink otherwise you may unwittingly poison yourself, loved ones, friends, and pets with engine antifreeze ingestion come springtime. You should be flushing the entire freshwater system multiple times in the spring too. ​ ​ Don’t forget to pink any cockpit or swim platform showers or nozzles or anchor locker nozzles. Don’t forget about any live wells or raw water washdowns. Some people opt for blowing compressed air through water lines. I have not tried this yet, for fear there would be some residual water finding its way to a low point, pool, freeze, and then crack a hose. ​ ​ Once on land open seacocks to allow any trapped seawater to drain; then reclose them. Plug your exhaust ports to prevent birds or other critters from making a home over the winter. Don’t forget the exhaust port for the genny. ​ ​ Toss any leftover anti-freeze in any areas in the bilge that may not drain or that you know are susceptible to water intrusion over the winter should a tarp fail. ​ ​ Remove your Gunnel Pups products, along with as many soft goods as you have room for, and store them elsewhere. Some folks dry-vac their soft goods and leave them on the boat. If you leave your cushions on the boat, standing them on the edge can help keep mildew at bay. Leave as many compartments open as possible and remember a few dehumidifier bags go a long way. Remember: The dehumidifier bags can freeze so leave them in an area that can handle the leak, if it occurs. ​ Check on the boat a few times over the winter. Don’t rely on the marina to call you if something goes awry. Bring your gunnel pup; they will be as excited as you are to see the marina. And if your pup is really well-behaved, you can take them on the beach for a quick polar plunge. ​ Then go home and over-obligate yourself to much-neglected home projects and visits to friends that were ignored over your entirely too short summer.

Questions? Email info@gunnelpups.com and I’ll get back to you.