You made a good choice. Many say the Excal (or a Sovereign, same machine) is the best there is in terms of water hunting performance in both depth and handling salt or mineralization.
Ism gives some excellent advice, as the bath tub thing was what I was thinking too. Far less risk to the electronics if they get wet in fresh water. Take the batteries out of the POD like he said, and then put the POD back on and submerge the machine in the bathtub for a few hours. Take it out and if no water is in the battery POD then shake the tube the electronics for the machine are in and see if you hear any water in there. If not, put some batteries in her and see if she works. If she doesn't then don't panic. Most electronics will work fine after they are dried out well. And then you can just send it to Minelab and probably there will be no need for any electronics repairs, but just to fix what is causing the leak.
I dropped a cell phone in a pond one night when I was camping. Actually it wasn't my fault. I was drunk (of course, I was camping!), but an idiot friend (also drunk) decided to pour camp fuel on the fire. Of course the fire ran up and into the can, so he threw the can into the pond. Only problem was he only threw it a few feet in, and so fire was slowly spreading from it with the risk of catching a big batch of dried cat tails on fire. I ran into the pond and sunk the can by hand to stop the fire from spreading more. In the process I dropped my cell phone in the water. A few hours later after it was good and dry by the fire it worked fine.
What p*ssed me off even more was I had warned him about doing that on a prior camping trip, because he at that time also caught camp fuel can on fire doing the same thing. He sat the can down (in the woods mind you) with fire gushing out of it and ran yelling "let's get out of here!" On instinct, I grabbed a jug of water and poured it onto the can and put the fire out. Dumb move, as the fuel could have spread from doing that all over me, but it worked anyway. I scolded him that he could have burnt the woods down but he ran off like a child, and he tried to make a joke out of it by saying we were just having camp fun. The funny part is I had the perfect line for that. I yelled back..."Camp fun?! If your idea of camp fun is giving somebody third degree burns or burning down the woods because you ran like a baby then you've got some serious issues!"
I was mad as h*ll that night, but these years later I can finally laugh about it. For a long time I couldn't. That's why the second time it happened, with me losing my cell phone, made me even more angry. Sure, I do some stupid things when I'm drunk and camping, but I always have enough sense not to risk starting a major fire or getting somebody burnt badly.
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