I lost a coolant hose going down the road and all my antifreeze was gone. I found a puddle along the road and filled my radiator back up after I fixed the hose. Will this cause electrolysis in my motor and ruin it? I drove 80 miles with it in there.
It's certainly not recommended, but I don't think it will ruin it, as long as you don't leave it in for too long...
Flush the coolant system thoroughly to get rid of all traces of contaminants, and refill with proper coolant - it might be worth then doing another flush a few days later if you're worried.
Electrolysis happens over time, and will not cause any damage over an 80 mile trip. People (wrongly) have used straight water in their radiator over the summer months thinking that's all they need and don't have issues until many years down the road. If you didn't worry about it and never changed it again, it would be an issue. Changing it out after an 80 mile trip will not be.
Sometimes you have to do what you have to do. That you could MacGuyver it back together and get it back on the road is testament to you not killing anything. Get it flushed and refilled with 50/50 and you won't have any issues.