Thoughts on -200 PG Antifreeze?

[Solstice]

I noticed that WM now has a -200 rated (pure) PG. Wondering if anyone has any thoughts on whether this concentration would have any additional adverse effects other than that of all PG products (rubber/Nitrile/Nylon deterioration). Any reason not to use for engine winterization (raw water side of course).
I usually use -100 just to be safe on my engine, but WM is offering this stuff with a rebate for $5 off a gallon, which makes it cheaper than the -100 I usually use. They also claim that it contains the same anti corrosion inhibiters as the -60 and -100. I've never seen PG available at this concentration, so wondering there may be any adverse effects at this concentration? Thanks in advance...

 

[Rich Stidger]

If it's cheaper (by reason of rebate) and has the same or better concentration and temperature protection, I can't see a reason not to use it. Most of these antifreezes provide "real" protection to a temperature about half of the label. So a -60 would be good in the real world to about -30, -100 to -50, etc.

But seriously, does anyone really live in a place that gets anywhere close to -100? I tend to think this is an example of marketing madness. If -50 is good, -100 must be better. Just my two cents....

 

[Solstice]

If it's cheaper (by reason of rebate) and has the same or better concentration and temperature protection, I can't see a reason not to use it. Most of these antifreezes provide "real" protection to a temperature about half of the label. So a -60 would be good in the real world to about -30, -100 to -50, etc.

But seriously, does anyone really live in a place that gets anywhere close to -100? I tend to think this is an example of marketing madness. If -50 is good, -100 must be better. Just my two cents....

Rich,
You are correct regarding the 'real protection'. I use the -100 on the engine to protect against residual water and therefore dilution. For me, spending an extra few bucks to protect my $$$$ engine is worth piece of mind. Maine Sail had interesting results when testing the actual freezing point of PG when winterizing an engine. I think he found that many folks don't use enough to counteract dilution, which confirmed my belief that when it comes to the engine, I don't want to mess around...

 

[Ralph Johnstone]

Just the Usual Marketing Madness

Pure PG has a freezing point of -80 F and that's all you get.

As for the -200 F PG, couldn't find it in their catalogue. If they are pushing -200 F PG, it's probably 100% snake oil.

BTW, does anyone know the freezing point of 100% snake oil ? WM just may be on to something after all.

 

[thinwater]

My company manufactures both PG and EG engine coolants, part of my job (chemical engineer) is developing new chemistrys, so I'm not guessing.

-200 products are 100% (nearly) PG. As Ralph pointed out, the minimum freeze point is ~ -65F, depending on the data source. Burst point is a different thing; there is no official procedure, but basically it is the temperature at which copper pipe may burst. Thus, a 50% mixture of PG will begin to freeze (slush) freeze at about -20F and burst (100% frozen and begin to expand) at about -65F. Also, it depends on whether we are talking about copper pipe (strong and tough) or PVC and cast iron (brittle). PVC bursts considerably sooner. Really, copper pipe burst points are of little interest to boaters.

Even though burst points are lower than freeze points, this is a dangerous gamble; upon repeated freezing the ice (water, at first) floats and the glycol stay low in the engine. Next thing you know you have water near the top, it freezes and something splits. Yes, antifreeze that is not formulated for minimum freeze point can stratify. We've broken enough pipe in our own plant to be certain of this.

The PG and inhibitors in all of the products should be the same when diluted to the same concentration. I wish they would just put % PG on the container. I believe WM does, though some others do not.

Why not use EG--regular automotive AF--instead? Less is needed (EG has better freeze protection than PG), automotive inhibitor chemistry is better tested, and the effect on the environment is LESS. Yes, less, because EG is slight more biodegradable, less toxic to FISH and less is used. EG is also less harmfull to rubber parts, one of the primary reasons no OEM uses PG in cars. EG won't ruin your neoprene raw water impeller as PG will (nitrile impellers are impervious to this). Using PG in marine black water and engine systems is a myth perpetuated by PG manufacturers and marine centers.

DO USE ONLY PG in your POTABLE WATER SYSTEM! EG is toxic to mammals, just not to fish. Don't take my word, ask the EPA.
http://water.epa.gov/scitech/wastetech/guide/airport/upload/2005_10_07_guide_airport_airport.pdf

Some additional information posted here:
http://sail-delmarva.blogspot.com/2009/11/marine-winterizing-antifreeze-and.html

Also this Practical Sailor Post. Nice photo of nylon strainer ruined by PG.
http://www.practical-sailor.com/blog/-11059-1.html
(no subscription needed for this)

 

[Solstice]

My company manufactures both PG and EG engine coolants, part of my job (chemical engineer) is developing new chemistrys, so I'm not guessing.

-200 products are 100% (nearly) PG. As Ralph pointed out, the minimum freeze point is ~ -65F, depending on the data source. Burst point is a different thing; there is no official procedure, but basically it is the temperature at which copper pipe may burst. Thus, a 50% mixture of PG will begin to freeze (slush) freeze at about -20F and burst (100% frozen and begin to expand) at about -65F. Also, it depends on whether we are talking about copper pipe (strong and tough) or PVC and cast iron (brittle). PVC bursts considerably sooner. Really, copper pipe burst points are of little interest to boaters.

Even though burst points are lower than freeze points, this is a dangerous gamble; upon repeated freezing the ice (water, at first) floats and the glycol stay low in the engine. Next thing you know you have water near the top, it freezes and something splits. Yes, antifreeze that is not formulated for minimum freeze point can stratify. We've broken enough pipe in our own plant to be certain of this.

The PG and inhibitors in all of the products should be the same when diluted to the same concentration. I wish they would just put % PG on the container. I believe WM does, though some others do not.

Why not use EG--regular automotive AF--instead? Less is needed (EG has better freeze protection than PG), automotive inhibitor chemistry is better tested, and the effect on the environment is LESS. Yes, less, because EG is slight more biodegradable, less toxic to FISH and less is used. EG is also less harmfull to rubber parts, one of the primary reasons no OEM uses PG in cars. EG won't ruin your neoprene raw water impeller as PG will (nitrile impellers are impervious to this). Using PG in marine black water and engine systems is a myth perpetuated by PG manufacturers and marine centers.

DO USE ONLY PG in your POTABLE WATER SYSTEM! EG is toxic to mammals, just not to fish. Don't take my word, ask the EPA.
http://water.epa.gov/scitech/wastetech/guide/airport/upload/2005_10_07_guide_airport_airport.pdf

Some additional information posted here:
http://sail-delmarva.blogspot.com/2009/11/marine-winterizing-antifreeze-and.html

Also this Practical Sailor Post. Nice photo of nylon strainer ruined by PG.
http://www.practical-sailor.com/blog/-11059-1.html
(no subscription needed for this)

Thanks Thinwater. I did read your excellent article in PS regarding the effects of PG on Joker Valves and nylon strainers--very informative and enlightening. The reason I am intrigued with the stronger concentration is because although I do blow out as much water as possible, my primary reason for using PG is to address low spots, the water pump and the bottom of my water tanks. Unfortunately I do not have inspection ports (yet) and the 3 tanks are very large with flat bottoms, so my goal is to offset this dilution enough so as to be safely beyond the slush point for temps in NE. I've always paid attention to the slush point and as you point out, the numbers associated with copper are useless for most boat owners.
I typically blow out as much water as possible, use a small amount of PG in each tank and then blow that out. Understanding that I am working with a *dilution*, the -50 is not very comforting considering that it can start to slush at a relatively high temp when diluted.
After reading your article, I am considering using EG in the Holding Tank and then when on the hard draining into a container since I have a gravity based HT (no macerater).

 

[Maine Sail]

Also, it depends on whether we are talking about copper pipe (strong and tough) or PVC and cast iron (brittle). PVC bursts considerably sooner. Really, copper pipe burst points are of little interest to boaters.

Universal & Westerbeke Heat Exchangers......

 

[Gene Foraker]

Don't forget there is also the factor of dilution. I put as strong as I can find in the bilge knowing that some water enters through the mast and winds up there.

 

[thinwater]

Universal & Westerbeke Heat Exchangers......

Exactly. In piping systems built to a known mechanical code you can tolerate some shushing; in composite systems you are going to have designs that can't tolerate expansion. I've found more hidden weak points in refineries than I can count. Valves (trap liquid inside when closed), strainers (often made of brittle materials) and pump casings (expensive...) are leading candidates.