i use alcohol also for stuff i want clean for applying something to stick or dry to it.
i used jb weld on a 76 or 77 buick regal v6 when the block rusted through and the coolant wouldn't stay in anymore. it was good size hole, like the size of a nickel when it finally broke through and my dad and i scraped and poked to see how bad it was. it was my first car and i loved it so i wanted to get it back to going really badly. after we did the jb weld, or maybe it was liquid steel, either way it was a two part stuff that had to cure afterwards. so we got it on and let it sit for a day or two and that thing never leaked again. i blew the turbo 350 before the engine ever died and that was the end of my cool guy boat-a-lac that everyone loved because we could put a bunch of high school kids in it, ha ha ha. we drove that thing all over east texas till the transmission died.