Thanks, Randy, I'm not too worried about my Volvo. As you say, the tank won't rust and I think the fuel injection system (Rex/Regina) is not too sensitive to a little water. I had a '72 Chevy in which the gas tank actually rusted through from the inside. I found a puddle of gas under the car one day. I plugged the hole with a sheet metal screw and took the car in for a new tank.

I'm more concerned about getting water into the fuel distributor in my MBZ. This is the same injection system I had in my '80 240 and I recall a warning about water and rust being the big enemies of that system.