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Radiator fluid mistake

I accidentally added windshield washer fluid to my radiator fluid. Will this harm it?

That’s impossible!


I’m sorry. I meant that I added windshield washer fluid to my radiator fluid.

Is it possible that the OP means that he added WW fluid to the radiator/cooling system?
Can the OP please clarify exactly what he was trying to tell us?

Yes. That’s what I did.

Don’t worry about it.

Washer fluid is just water with methyl alcohol and a blue dye.

Your coolant is about 50% water.


It’ easy to pour ww fluid into the wrong tank. In my car they are only 6 inches apart, although well marked what each one is! The one with the spray fountain diagram on top is the ww fluid reservoir.

How much did you add? I assume you added it to the reservoir…can you suck it out with a turkey baster?

If it is just in the overflow plastic bottle, figure out a way to remove it then refill the overflow bottle with the proper coolant. If it has already mixed throughout the vehicle’s cooling system, safest bet is to do a coolant drain, flush, and refill. Might be ok to leave it, but hard to say what effect the chemicals in the WW fluid might have on the various gaskets they’d come in contact with inside the engine.

The alcohol will burn off at cooling system temperatures. You will see the coolant level drop over the next couple of days or weeks. Just refill with antifreeze.

But that does beg the bigger question, are you loosing coolant? If you are having to add coolant on a regular basis, then you might have a bigger problem. If you just added a little WW fluid to the overflow that was up to normal level, then you don’t need to worry about anything.

Thank you.

I understood the OP. A simple mistake. There will be no consequences. Happy motoring.

I would caution @kurtjweber that while this mistake has no consequences, there are fluid mixups that can be disastrous. Please be careful in the future.