10M

I winterized the boat this year with antifreeze from my local pool place. It is either pink or blue -50F non-toxic, usually says R/V, pool, etc. This year it was blue, said Swimming Pool Plumbing Antifreeze. I put it in, but when cleaning up the bottles read the back and it said "not recommended for boat engines or auto radiators." Any ideas why? Ingredients include ethyl alcohol. I tried to reseach effects of ethyl alcohol online and can only find info about ethanol fuels. Is this bad for rubber? Bad for metal? Maybe it's ok? Thanks ahead.

teamsynergy

I believe it does not have the anti-rust corrosive protection...

CigDaze

Correct. It won't freeze, but's it's corrosive.

FIXX

iTrader: (2)

it reads not for cars because it dont have the cooling capabilities as regular antifreeze..make sure you use a refractor to measure the freeze point..the pink stuff reads will freeze at -32 which is a crock of chit,,on my refractor its only good for *18 above zero and its turns to slush at that point and will freeze rock solid at *0..beware head gaskets...

Even the -*100 below 0 that west marine sells is only good for -*50 below 0 which is still false advertisement..

RunninHotRacing163.1

MrFix used the green Sea brite 2 weeks ago and she tested out at -100 below 0 F.

boatnt

iTrader: (1)

They mean dont pour it in a radiator for a coolant because it does freeze/crystal form when temp drops under 12 degress but it does not expand so you can use it to protect a engine for a winter lay up and it does have corrosive protection.

10M

I'm not worried about it freezing and I know you're not supposed to use it in radiators/for coolant, I was more concerned about the corrosion. Does anybody know what the anti-corrosion chemical is so I can check if it's in the ingredients? I got mixed answers on here about whether it is or isn't ok to leave in. Right now it's in and i'm busy so it's staying in, but the motors are older and I don't want to have to open it up in the spring and replace rusted-through parts.

CigDaze

The alcohol-based pool/hvac/RV/Plumbing antifreezes are strictly for anti-freezing. They do nothing for lubricity, and anti-corrosion, and can be especially harmful to the older rubber used in our engine's cooling systems (most RV/Pool plumbing is PVC based which is practically impervious to alcohol)

The anti-corrosives can be as varied as apple pie recipes based on each manufacturer's proprietary blend but some common additives are sodium silicate, disodium phosphate, sodium molybdate, sodium borate, dextrin. Their main function is to neutralize the electro-conductance of the coolant solution so that there is minimal galvanic interaction between the various range of electrochemically incompatible metals in an engine (aluminum, cast iron, copper, lead solder, etc.).

A good automotive grade anti-freeze is best for winterizing our engines.

And the reasons that the label says not to use in an engine/radiator is because they are not modified to handle the hot-side of the spectrum (anti-boiling), and they contain no lubricants (say good bye to your circ. pumps).

BeakBoater35

The labeling on these antifreeze containers are rather misleading. This "-100 F", "-60 F" etc etc etc usually refers to the BURST point, not the FREEZE point. The burst point is the temperator at which the solution will damgae a pipe made from a particular material. Two commons materials sited are PVC and copper. The freeze point is the temperature at which the solutio begins to freeze. PVC or copper pipes would not be danaged at the freeze point, but the solution would not pump well through a curculating pump.

Examples: Burst Point Cooper Freeze Point

Sea Fit "-50 F" -50 F +12 F

"-60 F" -60 F +7

"-100 F" -100 F -60 F

jeffswav

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