NEVER use tap water to mix antifreeze with coolant.

Good = Distilled Water. Available evberywhere in gallon milk jogs like at WAL*MART.
Better - Demineralized Water.
Best - Deionized Water.

At around 1$ per distilled water bottled gallon, you can rinse through the upper radiator hose, with temp lever set to hot, and a catch pan under the engine block coolant jacket drain tap under the #4 exhaust runner.

Use a internal diameter 1/2" or 7/16" hose about a foot or two long.

Really best not to let antifreeze coolant spill anywhere. It does break down when exposed to air after some time, yet not after domestic animals try to consume it. Glycol antifreeze last much longer is spilled into water bodies like sewers and streams.

cheers,

Mac Dud.
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