Letting straight water sit in cooling system

jeremy_283

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Any harm in letting straight distiller water sit in my cooling system for two weeks (bike has not been rode, I'm just waiting for my engine ice to come in)
 
Nope - none at all. In fact, if you're running at most tracks...water is all they will let you run...
 
I would not keep sitting water for more than a day because it does not contain rust inhibitors present in coolants. Ever seen what happens to brake discs after a rain - they have rust on them the next day.

I would put a regular green coolant mixed with 50% water per their recommendation. Once you are ready to fill, just flush with water a couple of times and put in whatever different stuff you want.

BTW, I have engine ice in mine for a couple of years now.
 
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No problem for two weeks, but be aware that most commercial antifreeze products have corrosion inhibitors in them, so you really don't want to run water long term.

Here's a counter-intuitive tidbit for you. In general, you should use deionized or distilled water in your coolant, along with the antifreeze. However, without the antifreeze, this is probably worse than tap water. Why? Distilled water or deionized water is actually pretty corrosive stuff. The crap in tap water (usually "lime scale" or calcium carbonate) actually makes it less corrosive than ultra-pure water. This is not to say the chlorine in tap water is good for your engine, or that you won't get lime scale if you use tap water long term. That's why coolant flush is usually a mild acid to eat the calcium deposits.

The cheap gallon jugs of water from the grocery store will either be distilled or reverse-osmosis. You want the distilled water.
 
I use distilled water and water wetter. The key to remember is to change out to antifreeze before the freezing temps reach you or you will be sorry.
 
what will rust?

engine,water pump and radiator are all aluminum?

Aluminum and steel will both oxidize. With steel, it's called rust. Aluminum, it's called oxidation. Both occur in the presence of oxygen (water is 2 molocules of hydrogen, and one molocule of what??).
Straight water is never good in a cooling system, as heat is a catalyist for oxidation (or rust).
 
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