Why does everyone keep bringing up AppleCare? AppleCare does not cover accidental damage. AppleCare would not cover this accident.
Running the laptop under tap water was silly, but not entirely the wrong thing to do under the circumstances. The citric acid in the orange juice would have done way way more harm than tap water. With tap water, if it is dried very quickly, the device will still work. With OJ - no chance it will work. The thing that makes water bad are the salts/minerals dissolved in the water that increase how conductive it is (pure water alone is actually not very conductive), and standing water in connectors will cause corrosion and they will fail for one reason or another. So as long as the water is as pure as possible, and none is left in the laptop after all is said and done, rinsing under water isn't really so bad. The one huge caveat to that is the LCD - water will cause all sorts of damage there so when rinsing the circuit board, ensure none gets on the LCD.
Here is what the OP should have done, with the benefit of hindsight. This process might not still work, but I think it would maximize the chance of coming out of this accident with no issues.
- Immediately turn the computer over, grab the pentalobe screw driver, and open up the case to disconnect the battery. Corrupt files or lost saves be damned, just disconnect as fast as possible.
- Wash off the computer with water. Ideally, use purified and de-ionized water if you can get your hands on some quick. If not, filtered cold tap water would do. Initially dissolve maybe a drop of dawn dish soap in like 32oz of water or more, and add maybe 8oz of rubbing alcohol. Wash with that at first. Repeat until it's clean. Be very careful to not get any water on the LCD!
- Then wash/rinse again with half water and half rubbing alcohol mixture. This should hopefully wash away any of the minerals and soap in the water from the stop above, and will help the rest of the water evaporate.
- Then finally, quickly rinse with just alcohol to help any remaining water evaporate quicker and to ensure there is no residue from whatever was dissolved in the water.
- Use compressed air to blow the remaining liquid out of everywhere as much as possible.
- Leave it in a well-ventilated area to dry for at least 24 hours.