I'm wondering if this is a good option for when I flush my motors in the winter to avoid freezing. In the shed I found this garden hose attachment which is basically a bottle, valve and fittings, that I believe is to mix soap or fertilizers to water when using hose. What if I attached this to the hose with anti freeze loaded up when flushing my motors. Last couple minutes crack the valve and mix antifreeze into the system. Any one tried this or have an opinion??