PDA

View Full Version : Engine block freezing


causewayskiier
03-07-2007, 11:24 AM
Anybody have an idea how cold it has to get and for how long before there is a risk of engine damage? I un-winterized my boat then the temp dropped to around 27 I think, just wondering If that is cold enough to do damage?

east tx skier
03-07-2007, 11:27 AM
Stored inside or out? When you dewinterized your boat, did you run the engine in the water or just get it ready for the water?

JKTX21
03-07-2007, 11:53 AM
Ooops, the link I wanted to post has been deleted.

If your boat was indoors, it would have to be 27 degrees for a pretty long time to freeze your block. If the temperature just went down to 27 for the night, you should be ok.

Skibumtx
03-07-2007, 12:31 PM
I had the same question, the temp in Woodville TX dropped to 24 overnight a week ago; the boat is in a sling/boathouse about 2 feet over 60 degree water. I figured it would be alright and I did not want to drive 2 hours each way to fix it.

What does it take to freeze a block? I would think it would take a couple of days where the temp did not get above 32. Not much of a chance to winterize the boat this year, temp has been in the 50s-70s almost all winter.

Leroy
03-07-2007, 12:46 PM
There isn't a clear answer because there are so many variables.

Google expansion force of ice and similar terms for some interesting reading. The science says when Ice freezes it expands 10%.


Jim Stringer
Physiology, Palo Alto Medical Clinic, California One of water's most remarkable properties is that it expands when it freezes to a volume that is always 10% greater than in the liquid state. In other words, 10 cups of water put into the freezer is going to turn into 11 cups of ice when it freezes. This expansion takes place with tremendous force, as anyone knows who has left a full container of water with a tight lid in the freezer. The force is enough to burst the strongest water pipes if the water in them freezes, which is why people in cold climates sometimes leave a little water trickling through the pipes on freezing nights. It is not possible to make a usable pipe strong enough to withstand this force. Freezing water can burst a cast iron pipe over a foot thick. Water expands when it freezes because the molecules of water are actually closer together in the liquid state than they are in ice. Water molecules are polar, which means that they have positive and negative ends like little magnets. When water freezes, the molecules are held together in a rigid crystal pattern called a lattice, lined up with opposite charges next to each other. When the ice melts, the water molecules can tumble over each other and briefly get a little closer than they are in the solid crystal. This expansion is a very important phenomenon in the natural world. The force of freezing water is enough to crack open rocks and speed up the erosion of mountains. If water did not expand, then it would be denser when it froze, and would sink and soon cover the bottom of a lake or ocean. The oceans would fill with frozen water, and life as we know it in the oceans and on land would not be possible.

kpickett
03-07-2007, 12:57 PM
I haven't had a block freeze, but I talked about it with my mechanic. He told me that in his experience it needs to hit 26 degrees for three nights in a row to crack an undrained block....for what it's worth.

Bruce
03-07-2007, 01:10 PM
I am in the same boat (no pun intended) here. My boat is in a sling over water. I usually have lights in the engine compartment (V drive) to keep it warm. It warmed up I took out the lights closed the drain ran the engine with flush pro etc. Of course it turned cold again. 26 to 28 on a couple of nights. Local weather guy says 28 for four hrs. will freeze. I have observed that in my birdbaths. However, I don't think it is enough to bust a block. I guess I will find out in a couple of weeks.

Jesus_Freak
03-07-2007, 02:02 PM
...If water did not expand, then it would be denser when it froze, and would sink and soon cover the bottom of a lake or ocean. The oceans would fill with frozen water, and life as we know it in the oceans and on land would not be possible.

Yes, and that is one of the many proofs God is amazing.

The biggest factor is time. How long does your boat experience x temperature? Environmental thermal changes have to diffuse into the water inside the block and then freeze some volume(s) of the water. These frozen volumes may be continuous or disperse. Obviously, to do damage, there has to be enough frozen to bridge a channel inside the block. In addition, I imagine that the crystalline structure of the frozen water (and hence its expansion compared to the liquid state) would have something to do with the rate at which it was frozen. So, I dont have the answer, but it can be solved. :)

causewayskiier
03-07-2007, 02:34 PM
Yea the boat was outdoors, with a cover on it, and an insulated motor box. I think the temp. was around 27 for 4-5 hours. I guess I'll know soon if everything is OK.

Prostar Rich
03-07-2007, 02:46 PM
4 to 5 hours would not be long enough to damge the block. You should be fine.

Prostar Rich


Yea the boat was outdoors, with a cover on it, and an insulated motor box. I think the temp. was around 27 for 4-5 hours. I guess I'll know soon if everything is OK.

east tx skier
03-07-2007, 02:54 PM
Probably fine. Either way, the water in the pump housing would probably freeze before the water in the block would.

chudson
03-07-2007, 03:02 PM
4 to 5 hours would not be long enough to damge the block. You should be fine.

Prostar Rich

I wouldn't think so either, I'm not a mechanic but would a cracked block let water into the oil pan ( check the dip stick level ) just a thought!!!

Prostar Rich
03-07-2007, 03:20 PM
Cloudy oil would indicate a cracked block, a cracked head or a blown head gasket.

HTH,
Prostar Rich


I wouldn't think so either, I'm not a mechanic but would a cracked block let water into the oil pan ( check the dip stick level ) just a thought!!!

Matt L.
03-07-2007, 03:25 PM
Check you block freeze plugs too. They will push out in an attempt to prevent block damage.

Later,

Matt

Harvey
03-07-2007, 04:20 PM
Probably fine. Either way, the water in the pump housing would probably freeze before the water in the block would.

The water pump housing was frozen because I didn't bump the engine over when I winterized. It was the most horrible noise you ever heard when that belt went around the frozen in place pulley on the water pump. :o I haven't forgotten to bump the motor over ever since.

FOCUS
Assumming the boat is outside and in Texas, if they say it is going to freeze over night I take stock in the fact that my block won't freeze. If they say we are going to be below 32 for an extended period (more than 6 hours) I will worry. There are a number of factors to consider. If the temp the week prior was warm, say no lower than 45 at night then I wouldnt worry about the block freezing with a 4 hour block of temps below freezing (as the block itself is going to be warmer and would need longer exposure to freezing temps). If the temps the week before never got above 35, even during the day, then I might worry if the temp got low enough even in a four hour time frame. If the block has been cooled to 35 degrees over a week long period and you get 4 hours at mid 20 degree temps I would worry. At that point though you would expect it to last longer than 4 hours so need for concern would be obvious.

JKTX21
03-07-2007, 05:02 PM
http://www.littlegreenhouse.com/accessory/controls.shtml

Everyone that doesn't like to pull their plugs should invest in one of these and plug a lamp into it and put it in the engine compartment.

cm02WS6
03-07-2007, 08:46 PM
Man, back in the day I'd be able to figure this thing out. One thing to keep in mind is that you're talking about a relatively large "thermal mass" that needs to cool down past freezing. Your bird feeder (very small thermal mass) may freeze overnight, but that doesn't mean your boat motor will. The motor is relatively insulated from the outside by virtue of the fact that its sitting in an insulated motor box and surrounded by still air. Basically what I'm getting at is a night's worth of below freezing temperatures isn't likely to freeze the block.

That said, I also faced a similar situation this winter. I left my boat in the garage all winter and never winterized it. I figured it would be OK because the garage never freezes (I'm out there working with the heater on several times per week), but then I remembered the five days I was without power after a big ice storm and got worried. There's a couple of things I did to check block, other than visual inspection of the freeze plugs. I drained the oil and let it settle to see if there was any water left in the bottom of the jug (water is heavier than oil). Also, I took out each of my spark plugs and blew compressed air into each cylinder to see if any mist came out, and luckily none did. It looks like I dodged the bullet this time, but I'm definately going to be winterizing the boat from now on.

BriEOD
03-07-2007, 09:34 PM
Cloudy oil would indicate a cracked block, a cracked head or a blown head gasket.

HTH,
Prostar Rich
Or a problem with the intake manifold or gasket.