Assuming you had the power switch off on the PSU (or had it unplugged) during the install, then yes, air it out for a few days like the other guy said. I wash my keyboards about once a year in the dishwasher and they've never failed so long as they get several days to air out entirely before being plugged back in.
However, if you just had the PC off but the power still "hot" to the PSU (plugged in and not switched off), then you may be in trouble and already shorted something. Also, even if that is not the case, you may have gotten the liquid into places you don't see that can cause a problem if fired back up too early. My suggestion would be to disassemble the whole thing and let everything set out for a day or two.