Air don't freeze... RV antifreeze DOES!

[H20Rat]

Checked on on my summer place today, and happened to notice out of the corner of my eye that the jugs of -75 RV antifreeze were all sitting on the floor at an angle like there was something under them.

Turns out, RV antifreeze does a pretty good impression of a solid. It definitely expanded enough to bow out the bottom of the plastic jugs. Although there were some areas that looked a little like liquid, it definitely felt very solid.

Weather was about -13F last night, and had warmed up to about +5F.

In any case, if you have a use-case where expansion won't be a problem (sink P trap), not an issue, but if you have an engine filled with it, including relatively small water passages that might have had water mixed, you might have a problem at some point.

 

[Bob Sander]

Don't know why people use antifreeze when air is 100% free and much less messy.

 

[Lou C]

I’ve used -100 which was totally liquid at a bit below zero in my freezer and now I’m mixing up a batch of Sierra PG antifreeze 50/50 with water that gives freeze protection down to about -30. I use a refractometer to measure the freeze point of the mixture.
In fresh water you probably don’t need AF but for people like me in salt water I’m convinced it helps. Just the same as spraying my trailer leaf springs & u bolts with Corrosion X does. I’m still running the original block and intake manifold after 20 years of raw water cooling in salt water. It’s common for the intakes to rot out right under the thermostat housing…..
The Sierra works out to be about half the cost of the -100 pre mix and just a couple bucks more than the cheap -50 or -60 stuff which I would not use here….

 

[Scott06]

Checked on on my summer place today, and happened to notice out of the corner of my eye that the jugs of -75 RV antifreeze were all sitting on the floor at an angle like there was something under them.

Turns out, RV antifreeze does a pretty good impression of a solid. It definitely expanded enough to bow out the bottom of the plastic jugs. Although there were some areas that looked a little like liquid, it definitely felt very solid.

Weather was about -13F last night, and had warmed up to about +5F.

In any case, if you have a use-case where expansion won't be a problem (sink P trap), not an issue, but if you have an engine filled with it, including relatively small water passages that might have had water mixed, you might have a problem at some point.

Its is rated for burst protection not staying liquid. All of these will gel, then solidify depending on temp, they just don't expand enough to burst pipes At rated temp.

 

[paulswagelock]

Of course it freezes. -75 isn’t the freeze number, it is the burst point number, says it on the container. It is the temperature where it will expand and burst the media they declare. The manufacturer gets to pick what media they want to declare for the rating as there are no standards that apply. Some use PVC pipe for the rating.

 

[Bob Sander]

Its is rated for burst protection not staying liquid. All of these will gel, then solidify depending on temp, they just don't expand enough to burst pipes At rated temp.

That's the big difference with antifreeze. It's not that it won't freeze. It's just that is doesn't have the kind of expansive power water does when it does freeze.
Still... it's better to use air if you can. I'm in Manitoba and our Winters can go down to between -40 and -50 (even -63 once). Even vehicles with 50/50 mix of REAL antifreeze (not the cheap plumber stuff) will start gelling up if you don't have a block heater plugged in and working.

Now, I do use the plumbers antifreeze at our cabin in the drains and dishwasher, but I would never use it in a motor... not with our Winter temps anyway. Plain Jane air is the best if you can do it that way.

 

[Scott Danforth]

Ted did a freeze test about 8 years ago. yes it does freeze and expand

 

[Lou C]

But -100 won’t freeze till about -55*F and then there’s -200…
The problem with the antifreezes most people use is understanding the difference between freeze point and burst point.
Also when checking freeze points I think a decent quality refractometer is a must, the floating balls types tend to give unreliable (inconsistent) results.

 

[ahicks]

Bottom line, you need to realize that stuff WILL freeze. Many (way too many) have no idea of that potential and will learn the hard way. It's one of those lessons that people need to see for themselves.

I think one of the bigger reasons more aren't using air is the lack of an air compressor with the capacity to do a good job blowing the water out of a system.

 

[tpenfield]

People see the -50˚F or the -75˚F and think it is the freeze point. It is actually a 'pipe burst' rating and, as has been tested and shown, the AF does start to freeze and expand well above the burst rating.

What I have found is that with plastic components (fittings, valves, strainers, etc.) the -50˚F is not enough protection in many situations/areas, and some components will crack even at around -10˚F. My plastic sea water strainers would crack every year, until I figured it out.

Now I use -100˚F for the cooling system on my boats.

 

[Bob Sander]

Ted did a freeze test about 8 years ago. yes it does freeze and expand

The plumber's (or RV) antifreeze... yes, hence my reasoning for never using it in a motor.
The real stuff you use in a vehicle doesn't really expand.... or maybe it does, but the way it freezes can't harm a motor.... even if it does expand. It kind of flakes as it freezes. You can take a fork and hand grind frozen antifreeze into a rough powder pretty easily. Unfortunately because of its toxic qualities it really shouldn't be used as a general purpose disposable antifreeze.

 

[Lou C]

West Marine has a good article about this on their website, and they specifically do NOT recommend -50 or -60 for areas that get close to or below zero in winter. IMHO those are only good for very mild winter climates. Yet, that is most of what they sell. When my brother asked me to winterize his 2020 Chapparal with the Merc 4.5, I made him take back the -60 he bought and get -100. The new Merc's cooling system is FULL of plastic parts....

 

[Chris1956]

For sink traps we always used kerosene. That never freezes.

I used automotive antifreeze in my I/O. I would use it straight out of the bottle, and recover it for reuse in the spring. It also gave rust protection to the cast iron block.

 

[Lou C]

This is the cheapest, and the best alternative IMHO. Good enough corrosion protection to use as engine coolant, and if you have the refractometer you can blend it to give more freeze protection....50/50 with water gives approx -26*F.

 

[Scott Danforth]

air freezes at -361F

 

[Bondo]

air freezes at -361F

Ayuh,..... Even up here, 1/2 way to the north pole, it don't get that cold,.......
Though, today, 'n tomorrow it ain't barely gettin' Up to 0* f,.....

 

[Scott06]

This thread is starting to make me look forward to the next oil thread....

Must be winter and were all bored ....

 

[QBhoy]

Don't know why people use antifreeze when air is 100% free and much less messy.

Makes a hell of a mess with corrosion though !

 

[Lou C]

I think it all depends on your boating environment. I bet leaf springs don't rust to crap in 4 years in fresh water, but they surely do here. So my logic, I spray the springs 2x a year with Corrosion X they last me 8-10 years, and aren't even corroded just getting flattened out so I replace then. You are separating cast iron, and air salt serves as an accelerant. Why not do the same for the insides of your engine? Next time I change a thermostat I will take a pic of the inside of the intake on my engine used 20 years in salt water. It works for us, maybe totally unecessary in fresh water. A painted trailer will be junk here in 4-6 years. Galvanized is 20+. You separate the iron, oxygen and the acclerants of corrosion (salt and water).

 

[JimS123]

For sink traps we always used kerosene. That never freezes.

I used automotive antifreeze in my I/O. I would use it straight out of the bottle, and recover it for reuse in the spring. It also gave rust protection to the cast iron block.

I used to change the car's anti freeze at the end of the driveway and simply let it run into the storm drain.

I used to put the green stuff in the boat and simply let it run into the river when we re-commissioned the boat in the Spring.

Then, after reading Al Gore's book I got religious and I don't do any of that bad stuff any more.

Seems to me kerosene down the sewer might not be a bad idea.