anti freeze question

[duckman4548]

I am winterizing my 302fl for the first time since owning it, it is raw water cooled. I read where you can use RV anti freeze??? I have always seen conventional anti freeze used, just want to make sure I am doing it properly, Thanx

 

[Scott Danforth]

Read the stickies at the top of the forum. Air doesn't freeze

 

[Grub54891]

Your lical marina,or parts srore has it. Yes air don't freeze...but I just can't get peace of mind unless I run the -100 through it.....

 

[scutty]

There are lot's of differing opinions on this. Just like the classic debate of wintering with a gas tank full or empty. How do you know you got all the water out? The antifreeze will mix with whatever is left and provide extra insurance. Another common argument for using antifreeze is that whatever little bit of water or moisture left over sitting in a cast iron block with lots of air (oxygen) for 6 month is perfect breading ground for rust. So if you keep it full, less air means less rust. The only difference between the pink RV stuff and the Marine antifreeze you find at the local marine store is the marine stuff supposedly has extra additives (oils) to help protect against corrosion. However the RV stuff will serve the purpose. I don't think it is a good idea to use regular auto antifreeze. Though it would work fine it is toxic and you don't want it dumping out into your driveway or worse the lake in the spring. Conversely the argument against is that it ain't going to rust that much and why spend the extra $25 ( Mine takes ~5 gallons to fill up ) and the extra time and even this "environmentally" safe stuff is not good for the fishies either.
Hope this helps. For what it's worth. I fill my engine with antifreeze in the winter, the -50 stuff from the local west marine.

 

[tpenfield]

This time of year, Home Depot and lowes have Rv/Marine antifreeze in stock. Also Walmart .

RV/ marine type is non-toxic, automotive antifreeze is toxic.

The other posts reference the aspect of doing things properly. Essentially, running AF through the outdrive/engine does not yield the protection that one might think. You end up with a diluted mix of AF and water in various parts of the engine. In colder climates the engine still freezes and breaks.

 

[duckman4548]

So now I am really confused, if I drain the block via block drains, and use the west marine stuff after engine warm up I should be ok?

 

[Grub54891]

Just drain tne block,manifolds,circulating pump,oil coolers,run the anti freeze in. No need to warm it up, If ya run it with no water warmong it up,you will melt the rubber parts in the system.

 

[Starcraft5834]

this topic puzzles me to no end.... if air does not freeze, (which is does not) and water does freeze why would anyone put a water based substance into the block? the corrosion argument? what does that mean? LOL, we are talking about MARINE engines... they get wet!

remove what can freeze...= water....... even if you get "most" of the water out, what's left that does freeze does not hurt a thing.... I drained my new to me boat last year.. the "polar vortex" winter.. tossed some new points in this spring and vroom! it ran like a champ all year... I drained it again, except this winter, Im not stressing over it, and Im not throwing money away on pink..

 

[further]

My first year for winterizing as well (last year had a marina do it and they drained and back filled with the pink stuff). The manual for my 4.3 GS says to drain... no mention of adding antifreeze. I'm a bit paranoid and do feel its better to have the corrosion protection (whether it actually does something or not), so I drained per the manual and back filled through the hoses to the block and manifolds with a few gallons of the pink stuff. I do not agree, as most on here do, that running the motor and winterizing with antifreeze on muffs without draining, is an effective way to winterize. There is a high likelihood that the motor will not warm enough to open the tstat and circulate through the block which will leave nothing but water in places you don't want water. So just draining is best as said above....air don't freeze!

 

[tpenfield]

Yea, I'm going to help a buddy winterize this weekend. We run the AF, then drain everything.

I think what I will do as an experiment is to take some of the liquid that we drain from the engine block and the exhaust manifolds into a couple of plastic bottles. Then toss them into the freezer for the night.

I would expect those bottles to be frozen in the morning. . . . and the reason being is that they will not be 100% antifreeze, probably about 50/50.

 

[81 Checkmate]

Yea, I'm going to help a buddy winterize this weekend. We run the AF, then drain everything.

I think what I will do as an experiment is to take some of the liquid that we drain from the engine block and the exhaust manifolds into a couple of plastic bottles. Then toss them into the freezer for the night.

I would expect those bottles to be frozen in the morning. . . . and the reason being is that they will not be 100% antifreeze, probably about 50/50.

Be sure to ....Post up the results tpenfield

 

[Saline Marina]

Couple of things.

1. The green or orange automotive antifreeze is toxic to animals including you if you ingested it. I read rumors it also can contaminate your groundwater if you live on well water.

2. There is a tremendous amount of lake water stored inside the engine even after its been sitting "dry" for months. I estimate around a gallon and a half just from what came pouring out of my 4.3L as I disconnected all the hoses and opened all the drain plugs. So you can see how much pink antifreeze it would take to run thru there to get a mixture that's good to -25F assuming perfect dilution and no "dead flow" areas. Also you must make sure the thermostat is warmed and opened since all the first flow from the circulation pump goes out the exhaust. So you can't rely on pink coolant coming out the exhaust as a sure sign the job is done right.

3. I then proceeded to crank the trailer jack to full up and full down, even went 6" higher than full up to try to drain the bilge and get any more water out of the engine, again all plugs open and all hoses disconnected on the lower ends.

4. I could not sleep at night. Wondering if I had done the job right, its a high risk proposition to be wrong. I'd rather make more preparations now than have to source and change a motor next spring.

5. So I took off the thermostat housing and there in the intake lower manifold sits around 1/2" of pure water. Totally full would probably be 1-1/2" deep. So you can argue it's not going to burst but I can't sleep like that either. So I poured a gallon of pink, slowly, into the intake lower, letting it exit the drains. Then I closed the lower drains in the block and filled with another gallon. Now I feel a lot better.

6. For next winter, I have the thermostat housing in my machine shop. I plan to drill and tap the housing for a 1/4 NPT pipe plug so I can remove that and fill the intake lower without having to sacrifice a gasket. Will get some pics when I get the job done.

 

[Scott Danforth]

Ted, you could simply use a specific gravity tester and determine the freeze point. http://shop.advanceautoparts.com/p/...google&utm_campaign=gpla&utm_content=22983642

 

[lg260ss]

Couple of things.


6. For next winter, I have the thermostat housing in my machine shop. I plan to drill and tap the housing for a 1/4 NPT pipe plug so I can remove that and fill the intake lower without having to sacrifice a gasket. Will get some pics when I get the job done.

Why not just remove the large hose from the Thermostat housing and fill from there? There is no need to ever remove the thermostat housing to fill with antifreeze.

On engines with engine mounted impellers, I have always back filled with antifreeze to keep the impeller lubricated.

 

[tpenfield]

Ted, you could simply use a specific gravity tester and determine the freeze point.

Far too scientific . . . this is a boating crowd, not a physics forum

 

[Saline Marina]

Why not just remove the large hose from the Thermostat housing and fill from there? There is no need to ever remove the thermostat housing to fill with antifreeze.

On engines with engine mounted impellers, I have always back filled with antifreeze to keep the impeller lubricated.

I could, however there is more or less a mild restriction point in the casting, so I would need to source and attach a different hose angled upwards to pour into. If I drill and tap from above, I don't need to remove any hoses and the point of entry will be behind the restriction point, so all the flow should go downhill into the engine. However I'd likely need a funnel to feed a 1/4" NPT--sized hole. Pictures will make it clearer.

 

[lg260ss]

The hose I am referring to will take AF as fast as you can feed it. You fill the hose that goes directly to the engine water pump. I don't know what restrictions you are referring to, (the restriction in the Tstat housing perhaps?, if so, that is not an issue because you fill the hose that you pull off the Tstat housing). Just pull the hose to the side. insert a funnel, and fill until you see AF come out the opening left by the removed hose in the Tstat housing, reattach the hose and your done. I'd imagine filling through a 1/4" hole will take some time, but to each their own. i'd be interested in seeing the pics when it is done.

I've done it this way for 15 years owning a 4.3, 5.0, 5,7, and 6.2 engines. My current boat has a 6.0l which is fully closed cooled and all I have to do to winterize is drain the heat exchanger.

 

[tpenfield]

Be sure to ....Post up the results tpenfield

I will start a new thread to post the details and a video, but . . . .

I helped my buddy with a Searay 270 winterize his Mercruiser 7.4L yesterday.

We ran the engine for 20 minutes, then ran 4 gallons of -50F RV/Marine AF in through the muffs.

Then we drained the exhaust manifolds and block and water pump. As we did that, I took samples of the liquid in each manifold and the block, so 3 samples.

I stuck those samples in the freezer for the night. Freezer was -15F . I also stuck a sample of pure -50F AF in the freeze for reference.

In the morning each of the engine samples were substantially frozen - frozen hard . The reference sample of pure AF was frozen slushy, kind of like a snow cone. But the engine samples we much more frozen.

So, if you do not drain the AF, you are running a risk of a hard freeze, if the temps dip way below zero. I think many folks in Wisconsin and surrounding areas saw -40F temps last winter.

 

[Scott Danforth]

in conclusion.....Air doesnt freeze

 

[Bondo]

in conclusion.....Air doesnt freeze

Ayuh,.... Exactly,.....