Putting tap water in it might actually be your problem. That's going to have all sorts of minerals and crap in it, especially around here. That leads to corrosion and buildup as that stuff dissolved in the water collects and deposits in the radiator. Distilled water is pure, nothing else dissolved in it. Generally you want 50% pure water and 50% coolant in your radiator. Honestly I'd see about getting the radiator flushed and filled properly sometime soon. Hopefully there's no stuck buildup and that will help by itself. But for right now, if you can get some of the water out and get some coolant in there it will probably help.KitKatCara wrote: I put water in where it says 'special engine coolant' this morning. I've never put actual coolant in it. The radiator is brand new and what we spent so much money on. Nothing is blocking the fan, but I can't tell if the fan is coming on or not. In a few hours I will open the radiator cap and put water in there as well. I never put distilled water in it, just water from the hose. What will happen if I mix the coolant with the regular water?
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