Don't want the block to freeze but don't want to winterize either

bruceb58

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Re: Don't want the block to freeze but don't want to winterize either

Wind can be a factor. Not the same way it does as a human. That's why your radiator has a fan next to it...to aid in the heat transfer. Still air will trap the heat somewhat.
 

Silvertip

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Re: Don't want the block to freeze but don't want to winterize either

I don';t know if one of those block hearers will work without coolent being in the motor to transmit the hear.

The intent of the OP is NOT to drain the block. If there is no water in the block there would be no concern about freezing eh??????? The content of thermo-siphoning is not new. Water in the block would not "boil" away since there is not much heat involved. Warm water rises and puts the cold water back down. But if the block is drained one might as well drain everything else because the accessory stuff will freeze before the block does.
 
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Home Cookin'

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Re: Don't want the block to freeze but don't want to winterize either

You are correct, it take a decent amount of time below freezing to bring the inside of an engine (inside an engine bay) to freezing temps. If it was only a couple hours I wouldn't worry. All night several degrees below freezing?...best to be precautionary.

Also I'm not sure what you meant by wind being a factor, because wind is no factor for an engine.

Wind would blow away trapped heat--so an engine block in a doghouse is not at the same risk as a tilted OB full of water. Here, boats (OB's, of course) kept on a trailer can have the through-hull for a pump freeze and crack, causing catastrophic consquences when launched, that would not have occured had the boat been sitting in the water. And along those lines, when water temp is 40* and air is 27* then a boat sitting in the water is less likely to have any freeze issues for equipment near the waterline.

Case in point--although I drop my OB on my moored boat when we have steady temps below 25 at night, my neighbor on the creek with the same motor never drops his, and has never had a freeze issue in 10 years.

But my overall point is that the temperature of the air at the weather guage--or even at your porch thermometer--is not the same temp inside the engine block inside the doghouse, when the temps rise and fall 20* during the daily cycle. I may not deal with I/O but I live in similar temperate climate and deal with hoses, equipment, boats, plumbing in an unmanned hunt club, stuff in the garage, etc.
 

oldjeep

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Re: Don't want the block to freeze but don't want to winterize either

The intent of the OP is NOT to drain the block. If there is no water in the block there would be no concern about freezing eh??????? The content of thermo-siphoning is not new. Water in the block would not "boil" away since there is not much heat involved. Warm water rises and puts the cold water back down. But if the block is drained one might as well drain everything else because the accessory stuff will freeze before the block does.

True, but a block is not "full" of water when you park it in the garage. There is air and water depending on how much has drained itself out of the system on its own. You would have no guarantee that there was water in the freeze plug area and the manifold could be full.
 

bruceb58

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Re: Don't want the block to freeze but don't want to winterize either

There is absolutely no way I would put one of those block heaters in a core plug of a marine engine used in salt water. They are for cooling systems with coolant in them.
 

skydiveD30571

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Feb 13, 2012
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Re: Don't want the block to freeze but don't want to winterize either

Wind would blow away trapped heat--so an engine block in a doghouse is not at the same risk as a tilted OB full of water. Here, boats (OB's, of course) kept on a trailer can have the through-hull for a pump freeze and crack, causing catastrophic consquences when launched, that would not have occured had the boat been sitting in the water. And along those lines, when water temp is 40* and air is 27* then a boat sitting in the water is less likely to have any freeze issues for equipment near the waterline.

Case in point--although I drop my OB on my moored boat when we have steady temps below 25 at night, my neighbor on the creek with the same motor never drops his, and has never had a freeze issue in 10 years.

But my overall point is that the temperature of the air at the weather guage--or even at your porch thermometer--is not the same temp inside the engine block inside the doghouse, when the temps rise and fall 20* during the daily cycle. I may not deal with I/O but I live in similar temperate climate and deal with hoses, equipment, boats, plumbing in an unmanned hunt club, stuff in the garage, etc.

I see what you mean. You were referring to the trapped air around an engine acting as a sort of insulation but wind would blow it away. That's what I was referring to as well when I said it takes a while for an inboard engine to reach freezing temps despite the outside air temp.

I thought you were referring to wind chill which surprised me since I know you know better. Thanks for the clarification.
 

frantically relaxing

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Re: Don't want the block to freeze but don't want to winterize either

You guys need to do some experiments like my wife does for me un-intentionally- Leave some half-full bottled waters sitting in the truck that's parked out in the cold. I've witnessed those bottles go thru days of low 30's high temps and mid to high teen low temps, and the water in those bottles doesn't freeze. They'll obviously freeze when it's cold enough LONG enough. The engine in a boat's engine room is much the same as my water bottles-- The dead-air between the outside temp and the temp inside a truck or engine room acts as insulation, and it takes substantial time for the inside air to equal the temp of the outside air. But if your engine or water bottle is directly exposed to outside air, freeze time is much quicker.
 

chrisf695

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Re: Don't want the block to freeze but don't want to winterize either

You guys need to do some experiments like my wife does for me un-intentionally- Leave some half-full bottled waters sitting in the truck that's parked out in the cold. I've witnessed those bottles go thru days of low 30's high temps and mid to high teen low temps, and the water in those bottles doesn't freeze. They'll obviously freeze when it's cold enough LONG enough. The engine in a boat's engine room is much the same as my water bottles-- The dead-air between the outside temp and the temp inside a truck or engine room acts as insulation, and it takes substantial time for the inside air to equal the temp of the outside air. But if your engine or water bottle is directly exposed to outside air, freeze time is much quicker.

I completely agree with you on this, just this morning walking out of my condo it was 22 degrees... jumped in my jeep and all the left water bottles (5) that are half to qtr full of water were not frozen... it stayed 22-28 degrees for around 8-12 hours where i live... so i figure it would take alot more than last night temps and the amount of time for the block to freeze. Now with the whole day today being 34-36 and tonight being 20-24 degrees for 12+ hours.... I would be damn sure my block and manifolds are drained!

my .02....
 
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