About alcohol mixing with water - it does (and also dissolves at least some shellack buildup - I’ve used it full strength as a solvent to clean out little carburetors with success).
But back to water. Ages ago we lived in central Washington and had an old WWII Jeep that wouldn’t start in the very cold weather one day. Some guy said to pour alcohol in the tank, that it would sink through the gas and melt the ice. I thought “yeah, right “ but I needed the Jeep and figured there wasn’t anything to lose. I dumped a few glugs in, put the gas cap on and as quickly as I could get in and try to start it, it fired right up. I couldn’t believe it
__________________
Scott, Portland, OR '85 V-20 I/O, Merc 170