Windshield washer fluid question.

Messages
36
Location
Wisconsin
In my vehicles right now is your normal +32 degree fluid, all of them are at least half full in not more, I don't see myself using up all this stuff before it gets really cold outside, so my question is as follows. If I were to mix in one bottle (about 16oz) of 99% Isopropyl alcohol (rubbing alcohol) with the washer fluid would it lower the freezing point to where it would be good to use even in a Wisconsin winter? Would there be any negative affects to my windshield, wipers or pump and tubes? Am I crazy for thinking of this?
 
Messages
3,610
Location
Ponte Vedra Beach, FL
Instead of using the alcohol, just start adding some Rain X, -25 degree, windshield washer fluid to your existing fluid. I've done it every year, before winter sets in, and a hard freeze comes. Then just keep topping off with the -25 degree solution till late winter/early spring. Now I just use the Rain X since they make it for different seasons and it all mixes. I like to blend WWF just like oil...but all in the same family....if possible.
 
Messages
7,553
Location
North America
Originally Posted By: bprat318
In my vehicles right now is your normal +32 degree fluid, all of them are at least half full in not more, I don't see myself using up all this stuff before it gets really cold outside, so my question is as follows. If I were to mix in one bottle (about 16oz) of 99% Isopropyl alcohol (rubbing alcohol) with the washer fluid would it lower the freezing point to where it would be good to use even in a Wisconsin winter? Would there be any negative affects to my windshield, wipers or pump and tubes? Am I crazy for thinking of this?
I've done what you are suggesting, several times. I have found that the 90% evaporates out after a couple of days, so would suggest using the 70% since it doesn't evaporate. Plus, a 1/2 liter of rubbing alcohol is MUCH less expensive than even the 2.99 windshield washer fluid. You'll have slightly more degradation of the wipers if you do it for a long time(I never had an issue with the hoses), but for 1 tank of wiper fluid it will be fine.
 
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Messages
6,559
Location
San Francisco Bay Area
Originally Posted By: mongo161
Instead of using the alcohol, just start adding some Rain X, -25 degree, windshield washer fluid to your existing fluid.
We can't get that stuff in most of California, although I have seen it for sale in Nevada. I can find deicer at any auto parts store, but the only winter washer fluid here is concentrated with instructions on how much water to add for summer and winter conditions, depending on the particular county. They relax it for rural counties (called "type A areas") that see real winter weather, but even some of those are large counties where the most populous sections are at lower elevation and it rarely reaches freezing. Those counties are divided by zip code for this purpose. http://www.arb.ca.gov/consprod/regact/awwf/awwf.htm Once I saw some RainX "Booster". It was $2 for a 32 oz bottle. I could cut it with an equal part water to make a -25 deg F fluid for winter trips to Tahoe or something like that. I should have just cleaned them out since I haven't seen it since. It's the one on the right.
 
Messages
239
Location
ny
Try Blue Devil concentrate (Amazon)...comes in quart that's 4x the concentration of the winter jugs.
 
Messages
36,515
Location
ME
Regular blue -20 washer fluid is 70% methanol. I can't think of any cheaper alcohol per concentration. If you have to "fix" water into being washer fluid, try the -30 yellow stuff-- it's more than just alcohol. But I'd get your old stuff out of there. Depending on your setup you might be able to just unbolt the water pump from the bottom-- it seals with an o-ring. You can also remove the whole shebang with a bolt or two-- this gives you an opportunity to get all the pine needles and junk that collect in the crevice behind it.
 
Messages
1,048
Location
SE Wisconsin
Originally Posted By: bprat318
In my vehicles right now is your normal +32 degree fluid, all of them are at least half full in not more, I don't see myself using up all this stuff before it gets really cold outside, so my question is as follows. If I were to mix in one bottle (about 16oz) of 99% Isopropyl alcohol (rubbing alcohol) with the washer fluid would it lower the freezing point to where it would be good to use even in a Wisconsin winter? Would there be any negative affects to my windshield, wipers or pump and tubes? Am I crazy for thinking of this?
I researched this exact issue not too long ago... The link below shows the freezing points of various isopropanol/water mixtures http://www.engineeringtoolbox.com/ispropanol-water-d_988.html As you can see, you'd have to add quite a lot of isopropyl alcohol to reduce the freezing point to typical Wisconsin winter temperatures. A better solution is to add straight methanol. http://www.engineeringtoolbox.com/methanol-water-d_987.html According to this chart, you can reduce the freezing point to about 0°F by mixing about 24% methanol (by volume). FYI, the good, winter-blend washer fluid is typically about 35%(w/w) methanol in water, or about 40% by volume. So adding methanol to your washer fluid is not harmful at all to any part of your car. One cheap way to buy straight methanol is to buy HEET gas line anti-freeze/water remover. The yellow bottles with blue writing, $1.58/12oz or $5.97/48oz at walmart. Add two bottles to a half gallon of +32 will give you a freezing point of about -5°F. Three bottles will take you down to about -15°F, four closer to -25°F. Of course at that point, your (now 3.5 quarts) of washer fluid now cost you about $6.50. It is much cheaper to just squirt out ALL the +32 and re-fill with the $2.50/gal winter grade stuff. EDIT: Isopropyl alcohol will not harm anything, it has similar solvency properties to methanol. Your 16 oz of drugstore-grade isopropyl alcohol (actually probably 91%, not 99%) in a half gallon of +32 washer fluid, would reduce your freezing point to around +21°F.
 
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Messages
2,060
Location
America's Dairyland
Mongo & PandaBear have excellent suggestions. I have done both. Next time you buy washer fluid, get whatever you'll use in winter...when spring comes just mix 50:50 distilled water and you're good to go for summer. Cold comes and you go back to topping off with 100% winter stuff No more worries!
 
Messages
1,482
Location
Michigan
Wow, this is a lot of work for trying to save a few pennies. Why don't you just squirt the stuff out over the next week or so on your way to work every day and then fill up with the good stuff?
 
Messages
4,962
Location
Lima, Ohio, USA
Originally Posted By: BobsArmory
Wow, this is a lot of work for trying to save a few pennies. Why don't you just squirt the stuff out over the next week or so on your way to work every day and then fill up with the good stuff?
This is what i've normally done. When i bought this car last January, in the height of the dreaded "POLAR VORTEX", the dealer supplied fluid was Frozen Solid. it was a the better part of a month before it warmed up enough to siphon it out, or spray it away. replaced it with some Purple meijer MAXX 3in1 Fluid. i got on BOGO, with an additional BOGO coupon, that some how stacked, giving me buy one, get 3 Free. it's -25F, Rain Repellant, and Super-de-duper bug cleaner, Made by CUL-MAC Industries That Initial Fill (March) just ran out before my recent OC, so cracked open another Gallon, and i should be set for the Winter.
 

Kestas

Staff member
Messages
13,981
Location
The Motor City
I do what pandabear suggested and swap the fluid seasonally. It's not just to save a few pennies, but it gives you a chance to perform some maintenance and flush out the system and removes any doubt to the efficacy of the fluid.
 
Messages
3,602
Location
Parts Unknown
I just use it up (in fact, I did last week)... then switched over. if you want to save washer fluid... disconnect the line after the pump and before it splits into the 2 nozzles... and connect another use & barb to it... and pump it into another bottle for storage
 
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