If your battery is still good, not much acid leaked. At any rate, it would be too diluted by the rainwater to harm your boat. The biggest danger to the boat is waterlogged floatation, but two days is not nearly enough to waterlog it. Two or three weeks might do it in.
Battery acid is heavier than pure water, and tends not to float upward unless disturbed.
Last edited by John F; 05/08/17 08:21 PM.
