How long until block freezes/cracks

Long story short, my boat has not yet been winterized (was used a few weeks ago) and is in a fully enclosed non-insulated/climate controlled storage building in Austin, TX. It will be in he mid 60s today but a cold front is coming through tomorrow and the low Weds night is around 25. It will only be below freezing for 8 hours or so and then back up to the upper 40s on Thurs.

My main question is how long does it actually take to crack the block? I am guessing in a fully enclosed building it needs to be below freezing for an extended period of time to do damage but would love to hear others experiences. I have heard people say 24 for 24 (24 degrees for 24 hours), etc... Also, I do not have power to run a drop light, etc and am currently away from the boat... Any help is greatly appreciated.

I don't know if you could answer that question without a doubt. Just too many variables to consider really. The water in the block, risers, etc. could be frozen, but as long as there is sufficient space for that frozen water to expand the engine shouldn't be harmed. If all passages were completely full then the only expansion would be casting plugs, busted hoses, manifolds, block.

I don't personally think you will have problems unless it stays below freezing in your building over 24 hours. Then all those variables I spoke of come into play. As warm as the temps are today, and it will only be below freezing a few hours I think you're safe. Unless the building is some kind of metal structure with a bunch of air leaks where the air inside cools quickly, the air inside the building should be warm enough and insulated from the outside enough to save you.

Of course if you're truly worried the only real option is the winterize it so you can sleep soundly.

drop in a trouble light for peace of mind. but you should be fine. christmas lights, electric blanket, anything that will throw off just a little heat will keep things toasty in there

I wouldn't want to risk it. Like stated above, too many variables to count. From ballast to heaters and engines. Just go get it winterized if you can. If you can't, I would take it to a marina and leave it in the water with heat lamps in it over night. The water will help insulate it.

You'll be fine. Engines are very well insulated by fiberglass hulls under engine covers with padding, vinyl plus maybe some carpet. Throw in the building's additional protection and the engine probably won't even see freezing temps before the 8 hours are up much less get cold enough to freeze the water inside the engine.

I realize the OP can't but anyone else can run a quick experiment. Leave a cup of water on the floor of the boat under the cover. Check it in the morning. A single night won't freeze it (disclaimer, I'm in Austin too...this may not work anywhere that see's real winter). The water inside an engine will take much longer to freeze than a cup of water that isn't even under the engine cover.

Wouldn't hurt to at least drain the engine block if there's any way you can get to it. Peace of mind is worth a couple of minutes. Or even a few hours. That being said it sounds highly unlikely you'll have any freezing in this situation.

I'm in DC suburbs and my shop tells me that it would take about 3 days of damn cold weather to do anything to the block. I still winterize mine....

this guy put in temperature sensors in his boat for a 24hr period with similar temperatures. engine temp didn't drop that much. http://www.wakeworld.com/MB/Discus/m...21/392888.html

I can assure you that your block will not freeze until 10 minutes before you go to check on it. The nice part about that is it really does not matter how much it freezes after it has cracked so you don't have to worry anymore. For sure, this is one place where you are thousands ahead at 'better safe than sorry'.

If you drain the water out of the block, risers, heat exchangers and lines you will be fine. A trouble lamp can make the world of difference over a short time. Just drop it under the engine. (Turned on, of course)

Obviously nobody has read this mans full post, he cannot drop a light in and he is away from the boat - which is a problem.

My best advice would be to get to the boat and drain the block. Its more time consuming on a v-drive but shouldn't be hard. Once your block is drained I literally wouldn't worry about it at all.

I say drain block > trouble light 10 times out of 10

Thanks for the info/advice everyone. I am going to try and make it out there to drain the block tomorrow but it looks like it will only be below freezing for about 11 hours so hopefully I'm good if I don't make it... My schedule lately has been crazy!

Nothing to worry about... This comes up every year about this time... Here's the temp recorded chart..[IMG][/IMG]

Lowes among others carry propane heaters.

If you have a heater, be more worried about that. It is much more likely to freeze in those conditions than the block. Draining the block literally takes about 15 minutes and the heater another 15, if you have decent access to a line (make sure to blow some air through the line to empty the exchanger). Just do both if you are already there.

You have nothing to worry about with the temps that will be in the Austin area plus your boats is in a climate controlled storage. First thing, if your storage is a legit climate control building then it's built well just to keep drafts/wind out. That in itself is great. I store my boat just north of you in Temple, Tx. It's in a very good non-climate control storage unit (single units with walls to the ceiling and roll top door). Several years ago if you remember tgere was a hard freeze in central Texas in which ambient air temps did not get above freezing for 3 days straight. I put a digital thermometer in my motor compartment out of curiousity. The motorcompartment temp never got below 39 degrees in those 3 days. I also place several bottles of water where the roll top door opens and where it's coldest because of tiny drafts. Even those bottles of water never froze. You'll be fine with your motor...sleep well but if you have a heater (doubt that in Austin but you never know) drain that.

Originally Posted by Pad1Tai

Nothing to worry about... This comes up every year about this time... Here's the temp recorded chart..[IMG][/IMG]

Nice!

It seems to take a lot of cold energy to drop the block temps enough to have any impact. Some real science as proof...love it.

Like previously mentioned the main spots i would worry about would be the heater. Those are plastic and less exposed so are lot more susceptible to freezing then your block. Might be worth calling a friend to have them pull it to some place you can throw a drop light in there.

I personally would worry about it. It is out of the wind chill and would require a prolonged freeze of over 10 hours in the single digits to freeze it.

We had a deep freeze last year, I left a heater in the rear but I lost my heater core.

I would think that one of those $18 dip stick heaters would be enough unless you have items on a closed cooling system like the heat exchanger.