Outboard motor in freezing temperature

All manuals suggest to keep the lower unit in the water at low temperature while mooring your boat. That’s probably right if the water is deep enough around the boat. But if I’m going to leave my boat for a day in the marshy area and there is a danger that the marsh's surface will freeze up at night, thus the lover unit will freeze as well.
So may be it’s better to tilt the motor? Is it really true that in the tilted position some water is trapped in the lower unit?
I’m planning to go hunting and I expect that the bay where I’m going to might be already frozen. If the ice is not too thick I will break it up and leave the boat for a day. But I'm afraid that the water will freeze up again later in the day.
Any suggestions on that?
Thank you!

we brought a plumbers torch just in case

Your lower unit won’t freeze if it’s in the water. If you take the boat out of the water in freezing temps, lower the motor to drain the lower unit, and leave it down. Years ago, I hunted lots in freezing temps with no motor issues.

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Originally Posted by MarkD

All manuals suggest to keep the lower unit in the water at low temperature while mooring your boat. That’s probably right if the water is deep enough around the boat. But if I’m going to leave my boat for a day in the marshy area and there is a danger that the marsh's surface will freeze up at night, thus the lover unit will freeze as well.
So may be it’s better to tilt the motor? Is it really true that in the tilted position some water is trapped in the lower unit?
I’m planning to go hunting and I expect that the bay where I’m going to might be already frozen. If the ice is not too thick I will break it up and leave the boat for a day. But I'm afraid that the water will freeze up again later in the day.
Any suggestions on that?
Thank you!

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Really,the only concern is if the seals in the lower unit have been compromised and water has leaked inside. Freezing can crack the unit. I always lower the motor and crack the lower oil port between fishing season and duck hunting. It allows a small amount of oil to drain out. If there's water in the oil,it will look milky.If not,simply tighten the oil plug,open the top and top up. As long as the lower unit is in the water,unless the temps drop to -10C,the unit won't freeze. After the season,completely drain and change the oil and winterize as necessary.

If you ever hunt standing in water in waders in sub 0 temps, you can really tell how much warmer it is than the air. As long as the lower is submerged far enough to keep the water pump from freezing, down is the best position.

Thanks for clarification! Very appreciated!
Will follow these advises.

The whole idea of keeping the lower end submerged is to keep the water pump from freezing up. I had a bad experience down at Long Point, Lake Erie where the water level can go up or down at a whim and didn't notice the build up of ice and my pump was froze solid. Now if the motor is frozen in I remove the spark plugs and try to crank the motor by hand ( mine are 2 strokes pull starts); if it turns freely it should be okay to start if it's hard to cycle it may mean ice or near ice in the impeller and that means trouble. I myself would not recommend taking a torch to ice cold aluminum but if you can submerse the lower unit in a pail/bucket full of room temperature water ? As a disclaimer; I am not a mechanic , I learn things the hard way.

Longpointer,
Thank you very much for your post.
I have several questions though.
Firstly I don’t understand how a water lever could affect the position of the water pump (below the water surface or above) since your boat floats and as such the level of the boat and the motor in the water should not change.
Then, I think it’s a good idea to crank the motor by hand, but why did you remove the spark plug? It should not have a big effect on pulling the rope but it could be a big hassle to remove it in cold weather while your boat is still in water.

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Originally Posted by MarkD

Longpointer,
Thank you very much for your post.
I have several questions though.
Firstly I don’t understand how a water lever could affect the position of the water pump (below the water surface or above) since your boat floats and as such the level of the boat and the motor in the water should not change.
Then, I think it’s a good idea to crank the motor by hand, but why did you remove the spark plug? It should not have a big effect on pulling the rope but it could be a big hassle to remove it in cold weather while your boat is still in water.

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Removing the plug will only make turning the motor over easier…probably not necessary on lower HP motors…

Yes, that's was my thinking too.
Just wondering, do high HP motors also have hand start?

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Originally Posted by MarkD

Yes, that's was my thinking too.
Just wondering, do high HP motors also have hand start?

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My 75 Etec has. A rope came with it. I haven’t really investigated how it’s done…

No spark plugs means no compression and yes makes it easier to turn but allows you to also feel everything better. If you start yanking hard on the cord you may damage your impeller and God forbid if the motor fires up you will shred your impeller in an instance. An outboard motor must have cooling water from the moment it starts as it will overheat within a minute or two. I learned the hard way and my mechanic confirmed my lesson... Never, ever run an outboard motor dry !

The water went up and down thus encasing the lower end in ice thereby freezing my water pump and when it started the lack of cooling water caused a blown head gasket. What can I say ? I was young and strong like bull ... unfortunately also smart like streetcar. LoL !