It's That Time Of Year Again

"functionoverfashion" (functionoverfashion)
10/01/2019 at 11:49 • Filed to: None

It’s a tradition as old as “What oil should I use” or “What tires are the best” threads on any automotive forum. As the leaves start to change, and the temperatures drop, those of us in climates cool enough to warrant winterizing our boats will see a spike in people asking how to do it properly, which, on The Forums, provokes the following, more or less :

There’s no single right way to winterize a boat, for one, because there’s so much variation in cooling systems and other systems that demand attention before prolonged storage. But even among owners of identical boats, there remains debate about not only the extent of the procedures necessary, but the methods for even the most essential steps, namely, draining the cooling system of the engine.

I’m talking here about inboards, or inboard/outboards where “fresh” water is pulled in to cool the engine, then dumped out the exhaust. With the engine off, quite a bit still remains in the cooling passages of the block and other areas, and needs to be drained.

Basically there are three camps :

1. drain everything by pulling the appropriate plugs and hoses, done.

2. r un the engine while sucking in non-toxic antifreeze into the water intake until you’re satisfied that all the water has been displaced with a/f

2a . do #2 but also drain everything after the a/f is distributed

3 . drain it all, replace plugs / hoses then dump in a/f somewhere to displace/dilute any possible leftover water, or run engine it to suck in a/f like in #2.

Those are the three* basic camps, with really only #2 being questionable because what if there are areas where the water wasn’t fully displaced and the a/f mixture isn’t strong enough to prevent freezing. But if you run it long enough, OR if you get it up to temperature (t-stat open) before running a/f through the system, then it’s probably fine, if a bit wasteful as it takes far more a/f.

[ * 2a solves the problem raised by opponents of #2 on its own.]

#1 is the way things were done in the old days forever, because all you really need to do is get water out. But on a v-drive boat like mine, there are lots of hoses in the cooling system that could trap some water and cause trouble, so really, it’s best to both drain the water out AND replace it with non-toxic a/f in some manner. I also have a heater that has probably 25 FEET of 5/8 heater hose that needs to be drained, and the heater core is highly sensitive to freezing and thus displacing any possible remaining water with a/f is arguably mandatory .

Pretty straightforward, right?

The diagram above leaves out a lot, like the intake, strainer (to keep debris out of the system), the extra hoses required to actually make it to the v-drive and back (it’s on the opposite side of the engine from where it’s been added above), and of course the optional heater that I also have.

Whether you run it on a/f then drain, or the other way around, it’s not really important. Personally I fall into the third camp of draining first then running it on a/f, so there’s as little water as possible in the system when you start introducing the a/f.

Then there are countless other things to do - my checklist is pretty long - but none spark quite so much discussion as the “proper” way to winterize the cooling system and its accessories.

Happy Fall, Everyone!

DISCUSSION (28)

E90M3 > functionoverfashion
10/01/2019 at 11:54

I solve the problem of winterizing a boat by not having a boat.

For Sweden > functionoverfashion
10/01/2019 at 11:54

Just put the boat in a heated garage yo

functionoverfashion > For Sweden
10/01/2019 at 11:58

People say this, you know. “But I have a heated garage,” to which people inevitably reply, “but what if the power goes out during a cold snap?”

functionoverfashion > E90M3
10/01/2019 at 12:00

Hey, I mean, someone has to be “the friend who has a boat”

vicali > functionoverfashion
10/01/2019 at 12:01

Replace Boat with RV and we’re twins;

- d rain tank and water system ,

- u se compressor to blow out all faucet/tap/toilet lines,

- suck up antifreeze,

- drain.

- don’t forget to drain and isolate the hot water tank..

- also charge and pull batteries, empty cupboards, make sure windows and vents are closed, put in absorby dehumidifiers, put in mousetraps, lock it and walk away..

MonkeePuzzle > functionoverfashion
10/01/2019 at 12:02

my boats have always had sails...

...and lived in places that never get below freezing

nermal > functionoverfashion
10/01/2019 at 12:03

Same concept for RVs. For mine, I use an air compressor and a little plastic thingy to blast all of the water out with air, rather than sucking antifreeze through everything. Works great so far.

Sovande > functionoverfashion
10/01/2019 at 12:05

I have a fresh water cooled diesel in my boat and I open 4 gallons of pink antifreeze, open the sea strainer at the r aw water intake, fire up the engine and quickly pour in the antifreeze. When the last jug is almost empty I stop the engine and close everything up. The block holds 2 gallons so I am more than covered. I then drop a bilge heater by the block and plug it in. It has a thermostat in it which turns on under 40 degrees and turns at 45. My boat sits in the water year round. If we get a warm spell and want to go out it only costs about $10 to rewinterize.

For Sweden > functionoverfashion
10/01/2019 at 12:05

That's why you have a backup nuclear reactor

Long_Voyager, Now With More Caravanny Goodness > functionoverfashion
10/01/2019 at 12:06

How often is power out during a cold snap for long enough to even consider this?

functionoverfashion > vicali
10/01/2019 at 12:07

I keep my batteries in my basement, use them for backup power with an inverter - I can run our fridge off this system in a pinch.

I also use the moisture-absorbing buckets.

Oh and my boat has ballast tanks that need some a/f dumped in, just in case there’s water in/ around the pumps.

functionoverfashion > nermal
10/01/2019 at 12:08

The engine is the big difference, you can’t really blast out all the water, and part of the reason for replacing the water with a/f is to help prevent corrosion (rust) on the internal passages of the block.

Eric @ opposite-lock.com > functionoverfashion
10/01/2019 at 12:11

I don’t understand the obsession. Unless you’re running it in the middle of the winter or keeping it entirely full of water, a little ice won’t hurt anything. Just drain it and you’re good. Who cares if there’s ice in there?

There are other places were it matters, but if there are zones in the engine where water doesn’t flow, you have bigger problems.

functionoverfashion > Long_Voyager, Now With More Caravanny Goodness
10/01/2019 at 12:12

Certainly for us, I wouldn’t risk it. Even if the garage is 50 degrees, we get some of the coldest weather when a storm blows out and we can lose power for 12 hours during below-zero temps. That could be an issue for freeze-sensitive things in the garage.

That is, if we had a garage, and if it was heated, lol.

MonkeePuzzle > MonkeePuzzle
10/01/2019 at 12:15

of course, end of season has got some storage issues. gotta make sure things are well drained and stored otherwise you get mould and mildew :S

Michael > functionoverfashion
10/01/2019 at 12:15

I believe in drain, then fill with antifreeze. Air may not freeze, but the exposed steel can rust without anticorrosives or at least water keeping the oxygen away

functionoverfashion > Eric @ opposite-lock.com
10/01/2019 at 12:16

Part of the reason is supposedly to limit corrosion (rust) over the winter, of the internal surfaces of the engine along cooling passages. But yeah, if you can drain everything in a satisfactory manner, that’s all you *need* to do. With my boat, it’s not easier to drain everything completely, due to all the hoses everywhere.

With my old boat it was much simpler, and I only drained it. For years.

functionoverfashion > Sovande
10/01/2019 at 12:17

This is similar to what I used to do when I’d leave my boat in super late. I would just drain it, then put a light bulb under the engine cover (incandescent!) for a little extra heat.

Chuckles > functionoverfashion
10/01/2019 at 12:21

Just like your outdoor pets, boats should be brought inside when it's cold out

functionoverfashion > Michael
10/01/2019 at 12:22

This is one reason, for sure. The complexity of my system, along with expensive things at low points like the v-drive, make me do the a/f refill every time now.

Future next gen S2000 owner > functionoverfashion
10/01/2019 at 12:23

As much as I love sun pads, I really am starting to like outboards. Is the motor vertical? Yep, draining done. “Winterizing” is just stabilizing the gas and spraying some fogger oil in.

You forgot a 4th option, put your boat in a heated garage. Current garage is too small but I could stuff my previous boat and I think my current one as well into my old garage. 23' deep stall was amazing.

I’m also tempted to by this and do a swap. He should have been a little more proactive.

https://cosprings.craigslist.org/boa/d/florissant-2014-stingray-trades/6983321296.html

Future next gen S2000 owner > functionoverfashion
10/01/2019 at 12:28

... to which people inevitably reply, “but what if the power goes out during a cold snap?”

This is obvious. You burn your house down to keep your boat from freezing.

Sovande > functionoverfashion
10/01/2019 at 12:29

We aren’t allowed to use anything other than an approved bilge heater. I put it right next to the engine and it works very well.

https://www.xtremeheaters.com/

functionoverfashion > Sovande
10/01/2019 at 12:41

That makes perfect sense. My boat at the time was at my own dock, my own risk.

Eric @ opposite-lock.com > functionoverfashion
10/01/2019 at 15:35

In which case you just flush it with fresh water to reduce the corrosives and run antifreeze through it to coat it with non-corrosive liquid, but it’s not because it’s antifreeze, it’s because it coats it and inhibits corrosion.

Also, water can freeze all it likes in there as long as there’s a decent amount of air space, it shouldn’t damage anything. Water expands when frozen, but air compresses easily. The problem would come if you try to run it when there’s ice in there, but if you’re winterizing the boat, what’s the probability that you’d be using it when it is still cold enough for the water to be frozen.

Urambo Tauro > functionoverfashion
10/01/2019 at 20:06

And d on’t even get me started on “freeze” plugs , as if they’re supposed to save the block from cracking...

functionoverfashion > Eric @ opposite-lock.com
10/02/2019 at 10:09

Right, I mean, draining only is a perfectly good way of doing it. The little bit of water that remains won’t do any damage.

Another reason (for me, the most compelling) for re-filling the system with a/f is that it makes spring start-up easier. All the plugs and hoses are in and connected and there are fewer air pockets to cause issues with priming the system and getting proper water flow going.

functionoverfashion > Urambo Tauro
10/02/2019 at 10:10

Oh, don’t you DARE call those things freeze plugs on The Forums.