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I accidently put Windshield Wiper fluid in the Coolant Reservoir



  • edited January 2010
    I would take 1/2 the water out of the tank and refill with straight antifreeze. I hate the 50/50 stuff, most cooling systems are very hard to drain completely . I always drain everything I can, flush with water until I'm sure water is the only thing in there then drain, refill with 50% of capacity of full strength antifreeze then fill with water until full. Then I mix up some 50-50 and fill the overflow tank and keep a gal of the mixture in the car to top off the cold radiator until it stops needing any.
  • edited January 2010
    3/4 of the bottle? And you've driven it?
    Personally I'd drain and refill the system. Rub some coolant mix and some window wash fluid between your fingers. You'll find the coolant mix slippery and the window wash not. As a matter of fact, you can probably wash the slippery coolant mix off your fingers with the windshield wash.

    The reason for the slipperiness is the additives used as corrosion inhibitors and lubricants for the water pump. You may have effectively washed much of these additives off the surfaces of the engine's insides and the water pump. You want the cleaning fluid (window wash) out of the system and the corrosion inhibitors and lubricant back on the engine's the proper strength.

    JMHO. Why not spend $5 to protect the insides of an engine worth a few thousand.
  • edited January 2010
    In the "good old days", meaning the 1940's through the mid 1950's, we had two types of antifreeze. There was permanent antifreeze and an antifreeze strictly for winter use. DuPont's permanent antifreeze was called "Zerex" and the non-permanent antifreeze was called "Zerone" As I remember, the Zerone would boil at 180 degrees. I think the windshield washer fluid may not be too different chemically from the Zerone antifreeze. The Zerone was not ethylene glycol as was the Zerex and other permanent antifreezes. I think Zerone was menthanol, but I'm not sure.
  • edited January 2010
    I don't think it will come out, but form an azeotropic mix instead. Alcohol can be pretty corrosive. I would do a coolant exchange.
  • edited January 2010
    Well, I wouldn't worry about it.
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