Can a 496 be damaged with freezing temps?
 

I have a friend with a 496 mag ho. He stores this boat inside every winter but this year was slow to tow it to the storage facility. With the boat sitting outside we had hi/low temps of 32/19, 34/24 and 34/23. I would assume the block is safe but the manifolds? Heat exchanger? Anything else he should be concerned with?

If you are unsure, go to Petsmart and get 2 (or 3) clip on Lizard heaters. You clamp them on and either put them on a lamp timer or leave them on.


You will be surprised when you check on your boat and the engine is WARM...

If everything was drained and blown out of freshwater shouldn't be a problem.

Nothing was drained. It came out of the lake and sat for almost 2 months.

The Heat exchangers need to be looked at IMO. There is a little hand pump under the hood that could have been used.

Is this 496 a closed coolant system? If so I would imagine it would be just fine. If not, it really doesn't matter what engine it is, doesnt take much to do major damage. Either way, I hope it's ok!

Three days at those temps he should be at the edge on the very concerned list . Probably not long or cold enough to do damage but he better move on it soon . $$$$$$$$$$$

I'd check it over, but chances are it is okay.

Agreed. Doesn't take much to freeze the small amount of water in engine blocks acting like freezers!

The 496 is a closed system so the block has antifreeze in it all year. The heat exchangers have hand pump for blowing them down, but the damn thing needs winterised.

I have antifreeze in my exchanger this time of year.

Yea I asked if it was a closed system in pervious post. So the heat exchangers use fresh water? Not real familiar with the closed system engines.

He's in trouble. Those heat exchangers are probably toast, and maybe more.

I know I've posted at least 100 times on this topic so there is plenty that will come up with a search. The 496/HO water drain actuator system is NOT to be used for winterizing.

Yeah, the heat exchangers draw fresh water and cool the closed system antifreeze.

If these exchangers freeze and bust, the boat will take on water next year and not cool the motor correctly.

Like I said, there is a little hand pump to blow the exchanger down to extend the season, but in cold envionments were it is below freezing for exended days and nights, it will not be enough.

If his "friend" would have done the blowdown and put it inside a building, I would say he would be fine for now.

Around were I live, you could have picked up the phone and a service place would come out, winterise and even place it in storage for you and just send the bill.

Oh ok, makes sense now.

And yes, same around here also. I keep mine at a marina and winterize it myself for a few years now and they still call me to make sure I did.

Worse yet, how is your friend on overall maintenance and upkeep? If there have been any previous issues with antifreeze/freshwater crossing over, he could have water in the block and that would freeze.

IF the antifreeze tank appears pink, there would probably be enough antifreeze in the "solution" in the block that would protect from freeze damage to the block. Such was just a passing thought though.

Makes sense to me Joe. If you have time and know how to do something right, it is best to know for sure and do it yourself.

Alot of fly by night operations could cost us too much money
cutting corners.

I use a stand up dealership that would stand behind any mistakes. They have a big tank and recycle plus they use a hydrometer to ensure what temp I am good for.

I always hate to see winterisers dump on the ground and am scared to death to walk my dog around the marina this time of year.

I'm sure you do a great job. I guess this "friend" may learn an expensive lesson.

He pays someone every spring to get her ready for the season. He typically doesnt winterize because it sits in a heated warehouse all winter. This is the first year he has waited this late in the season to get it indoors.

I could not stand to not know if everything is OK or not, I would get it looked at pronto.

I think that Mercury says to check the antifreeze as part of the winterization process, as any small leak could be cause for cross contamination. Assuming that the antifreeze is good, the block should be OK, but I bet the exchanger, cool fuel, exhaust, pump, etc. are toast. It is amazing how a small amount of water can freeze, expand, and crack big hunks of steel. That said, for your friends sake, I hope that he is safe.

If it thaws and then freezes again, the water from the busted exchanger could very well dilute the antifreeze to the point that the block coul crack with the next cold temps.

Please let us know how it all turns out.

Its fine

I would throw some heat at it before he puts it in storage regardless. Good luck but I also think it should be okay.

I agree.

There are a lot of things to consider. Was it covered? If it was covered, at least the vents didnt have air blowing around the engine compartment. When its zero outside it is usually including windchill. Since the engine compartment is closed, its not toasty, but it isnt 15 below either.

Worst case scenario is probably the exhaust cracking. This could be looked at favorably as you could upgrade it next spring. If its the closed cooling log it still isnt that expensive. The engine has coolant, so its fine.

I had a 496 and pushed the limits a few times and was ok, but 19 is a whole different ball of wax. I'd be concerned.

The cockpit cover was on but thats it for cover. I would tend to think the block is fine but the exchanger, the exhaust manifolds, oil cooler, water pump etc could all be affected. All i know is ANYTHING with water outside was frozen.....SOLID.

If stuff was frozen "solid" outside, $hit aint gonna be good

Well heck run a hose to it and start it up! LOL At least you'll have an early start on fixing it for the summer if it is broken.

Possible check valve and or cool fuel internally especially the GEN III cool fuel. That needed to be thrown in the mix ALSO since those two items was not mention. I don't care what Mercruiser motor you have if it has a Gen III cool fuel system they all need to be drained. We winterize about 85 min. of those alone and you would be surprised how much water the Gen III cool system holds after you drained eveything else.

What would a guy from Florida know about Cold weather anyway........:D :cool-smiley-011:

I'm a Pennsylvania boy. I know what snow is! And I lived in Georgia for 12 years and it got down under 30 degrees there TWICE! So there!


By the way, its 80 here right now, how it is up there? LOL :evilb:

I would guess he has about a 50/50 chance that no damage was done.
The ambient temps are borderline for getting water to freeze. If the daytime highs were higher, I wouldn't be concerned. If the boat was in the sun, that will help also.

It's colder than a well diggers ass here .:poopoo: I wish I could escape , I'd come down and take you up on that beer .

I'm with him^^^^^^

Dude its called Spirit Airways.... Get off your a$$ and drive to the airport.

Latrobe to Ft Lauderdale is cheap too!

It's correct that the little air pump does not get all the water out. My boat came with a 496 and I lost a heat exchanger one winter. A used one cost $400. After that I started unhooking hoses and blowing the water out with air pressure. The symptom of the bad heat exchanger was that the antifreeze was dropping and coming out the exhaust while running on the hose. He may have gotten lucky if day temps were above freezing. Hopefully he has now properly drained the raw water side and he will find out in the spring by running it on a hose.

Man that hurts! I used to live in Miami so I know what I am missing. I could fly down for a week, but the trouble with that is I would have to come back and that would just make things worse.

I do want to come down for the boat show in Feb. however.

It takes about 10 min to use the little pump on the front of the motor and drain the exhaust... I would definitely check the heat exchanger! I would say it is going to have some issues

Ice, under ideal conditions can generate about 114ksi of force. That's well beyond most steels yield tensile and probably past the ultimate tensile as well.

In other words, don't mess with physics.

Just thought of something else useful. Ditch the little blue pump. It is a pain in the rear end. Go to Advance and pickup a $15 cigarette lighter tire pump. Keep it in the boat and hook it up when you are ready to winterize. Turn it on and multi task... Will take less than 5 minutes and prevents false readings/you might think its empty when its not. Sometimes as the little blue poppits get old they get sticky and fussy.

When I was in Georgia we used the boat during the winter for an occasional booze cruise and this made it fast & easy. Later I came up with reptile heaters that were even easier but the cigarette lighter pump worked well.

The little blue pump, or what ever you use to pump up the system; does not REPLACE the water as one might think.

It just charges a closed system that opens two drain actuators. You can use a 12V Air Compressor, an air tank, or a bicycle pump. There is an automatic air pressure purge valve.

Start this fugger up lets get to bottom of this