Winterizing indoor stored boat.

ryno1234

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Dec 8, 2014
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My boat is stored in boat storage facility indoors. The facility is not heated, however it is closed up from the hours of 6pm - 9am. Additionally, I live in Northern California in the valley where it rarely hits below freezing overnight.

My prior boat I never winterized and it was stored at the same facility. I never had an issue with it for the 11 years I owned it... (call it dumb luck?). To call out some specific things I never did prior to winter that I think *could* be important, I never:
  1. Added fuel stabilizer
  2. Drained the block / manifolds
  3. Fogged the engine
  4. Sprayed anti-corrosive on the exterior
  5. Put oil in the cylinders
  6. Added oil to the fuel filter and ran the engine until it died (why the hell is this suggested?)
My new boat I'm trying to baby more so I figured I'd put in the effort.

I have a few questions:
  1. How important are these processes when the boat is stored like mine is? It's out of the elements, although may occasionally, but briefly hit sub-32 degree temps.
  2. I drained the block, but forgot to add the fuel stabilizer to the tank so I'll have to redo this process if I'm to work the fuel stabilizer through the fuel lines (although I can still add stabilizer to the tank, it just wouldn't be through the lines). Again, how important is this part? I've never had an issue starting the boat up the following year with the fuel in the tank.
  3. Related to above, I also forgot that I'd need to fog the engine before I drain all the water from it. How important is this?
  4. For the first time I also have some systems I've never had before and am very unfamiliar with: Septic, Potable water, Heater unit (not sure what this is called... it takes hot water from the engine and runs the potable water through some sort of heat exchanging lines to give hot water for showers, etc.) I haven't used any of these systems since buying the boat, largely because I'm still understanding how it all works. The septic system is "empty" (as close as you can get), the potable water is about half-full and I have no idea about the heat exchanger thing and how that might play into this.
Complete side note: One of the blue drain tabs on the starboard side of the engine didn't have any water come out. I stuck a screwdriver in there and broke free rust which then allowed the water to come flowing out. I'm *somewhat* concerned, because earlier this year I found that I had an exhaust manifold with almost all of the water ports sealed shut with rust. I've since replaced both manifolds and risers, but I'm concerned that that these might be indicative of an issue in the block.

I know this is a lot - thanks in advance!
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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as long as you trained the block.

the water not coming out of the one port is an issue. remove the adapter from the block and probe with a stiff wire.
 

JASinIL2006

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I would not worry at all about the fuel stabilizer or engine fogging if you're only storing over winter. If it's already in storage, I don't think I'd pull it out to fog and stabilize just for a few months.

As for draining the engine block or not, it's a bit of gamble. If the boat is never exposed to temps in mid- to upper-20s for several hours, you'll probably be OK. But as we've seen lately, places that never used to get hard freezes are now occasionally seeing those kind of temps. Personally, I'd drain the engine block, but it's hard to know if it's absolutely necessary.

Can't help with question 4.

Good luck!
 

ryno1234

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Dec 8, 2014
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As for draining the engine block or not, it's a bit of gamble. If the boat is never exposed to temps in mid- to upper-20s for several hours, you'll probably be OK. But as we've seen lately, places that never used to get hard freezes are now occasionally seeing those kind of temps. Personally, I'd drain the engine block, but it's hard to know if it's absolutely necessary.
Just to be clear, the block IS drained. That I did do, but I did it before I thought about the fogging / stabilizer. From what you're saying, sounds like that might not be that big of a deal :)

Thanks!
 

crazy charlie

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Just to be clear, the block IS drained. That I did do, but I did it before I thought about the fogging / stabilizer. From what you're saying, sounds like that might not be that big of a deal :)

Thanks!
You can still partially fog the motor Pull the plugs one at a time and spray some fogging oil into each cylinder.You can then "bump the ignition just to have the pistons move a little.If you have a carb,spray some fogging oil into the carb before bumping the ignition.This way would be better than not fogging at all.Charlie
 

ROY WILLIAMS

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I sucked out the gasoline ... also I inspect the out drive take it off lube it and inspect the gear oil,, gimbal housing is inspected the bellows is very clean and no wears on it .. no cracks ..

you also did my engine in the winterize it ,, good job ///...
 

crazy charlie

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I sucked out the gasoline ... also I inspect the out drive take it off lube it and inspect the gear oil,, gimbal housing is inspected the bellows is very clean and no wears on it .. no cracks ..

you also did my engine in the winterize it ,, good job ///...
Roy, are you sure that you are commenting on the correct post???
 

Lou C

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Nov 10, 2002
Messages
13,065
I would say at a bare minimum:
Change oil & filter; if oil is milky that needs to be dealt with over the winter May need engine repairs…
Change drive oil; same thing if you see milky oil get it fixed over the winter…
Drain block & manifolds (sounds like you already did this), rust in the drains suggests that adding AF might be a good idea in the future since internal rusting happens in engines left dry over the winter. I always added AF to mine & most years the drains don’t clog…
Fogging? If indoor storage in a dry climate not so necessary.
 

ryno1234

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Dec 8, 2014
Messages
136
Drain block & manifolds (sounds like you already did this), rust in the drains suggests that adding AF might be a good idea in the future since internal rusting happens in engines left dry over the winter. I always added AF to mine & most years the drains don’t clog…

I read another post (https://forums.iboats.com/threads/rust-in-cooling-system.617837/) where it was stated that rust in the cooling system is expected.

In my previous boat, which I mentioned above, I never drained the cooling system prior to winter and, when I did (during summer occasionally) I never saw rust, at least none that caught my attention.

So, does keeping water in the cooling system help slow the creation of rust (due to lack of oxygen)? Similarly, why wouldn't everyone be adding antifreeze to their blocks after winterizing to ensure that rust doesn't occur? These seems to me like a mandatory step, otherwise wouldn't your engine just rust out over the course of years?
 

Lou C

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I read another post (https://forums.iboats.com/threads/rust-in-cooling-system.617837/) where it was stated that rust in the cooling system is expected.

In my previous boat, which I mentioned above, I never drained the cooling system prior to winter and, when I did (during summer occasionally) I never saw rust, at least none that caught my attention.

So, does keeping water in the cooling system help slow the creation of rust (due to lack of oxygen)? Similarly, why wouldn't everyone be adding antifreeze to their blocks after winterizing to ensure that rust doesn't occur? These seems to me like a mandatory step, otherwise wouldn't your engine just rust out over the course of years?
That’s what the whole debate about adding antifreeze is all about. And I’ll say this…I’ve done it for 20 years same engine not rusted out in salt water use. Mercury Marine now requires that AF be added to the raw water side of the cooling system to reduce corrosion. That’s really up to the owner.
 

tpenfield

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I'm late to the party, but here are my comments . . .

  • How important are these processes when the boat is stored like mine is? It's out of the elements, although may occasionally, but briefly hit sub-32 degree temps.
The main risk is if you have an extraordinary weather event or pattern during the winter months. Ask the folks in Texas about that. Draining is fine for this

  • I drained the block, but forgot to add the fuel stabilizer to the tank so I'll have to redo this process if I'm to work the fuel stabilizer through the fuel lines (although I can still add stabilizer to the tank, it just wouldn't be through the lines). Again, how important is this part? I've never had an issue starting the boat up the following year with the fuel in the tank.
Fuel stabilzer is a good thing to have, but you really needed to add it prior to a recent fueling, so it would be well mixed with the fuel. The fuel will probably be OK, but you will want to add a whole bunch of fuel system cleaner (injector cleaner) during your pre-season prep.

  • Related to above, I also forgot that I'd need to fog the engine before I drain all the water from it. How important is this?
Some folks don't fog their engines . . . .since you are indoors, it is probably OK.
  • For the first time I also have some systems I've never had before and am very unfamiliar with: Septic, Potable water, Heater unit (not sure what this is called... it takes hot water from the engine and runs the potable water through some sort of heat exchanging lines to give hot water for showers, etc.) I haven't used any of these systems since buying the boat, largely because I'm still understanding how it all works. The septic system is "empty" (as close as you can get), the potable water is about half-full and I have no idea about the heat exchanger thing and how that might play into this.
You should have drained the water system (tank and lines) and blown air through all the pipes. It also sound like you have a water heater (gets its heat source from the engine). . . It also can run off of shore power (most likely). That should be drained. There is an outdoor faucet looking valve low on the unit that can be opened to drain the internal water tank.

Your main risk with the domestic plumbing is freezing. You should (have) add(ed) some Marine/RV antifreeze to the toilet and the water tank, and pumped some of the AF in through the pipes. That way if you get a slight freeze, you will avoid potential damage to the pressure pump, toilet, etc.


Complete side note: One of the blue drain tabs on the starboard side of the engine didn't have any water come out. I stuck a screwdriver in there and broke free rust which then allowed the water to come flowing out. I'm *somewhat* concerned, because earlier this year I found that I had an exhaust manifold with almost all of the water ports sealed shut with rust. I've since replaced both manifolds and risers, but I'm concerned that that these might be indicative of an issue in the block.

Engine blocks are usually filled to some extent with rust flakes, sand, and whatever else gets sucked into the cooling system (assuming raw water cooled engine(s)). Generally, the sediment in an engine block is not a concern, unless it becomes extreme. You did good to probe the drain to allow the water to come out.
 
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