you put oil in there to prevent corosion, all but a very small ammount of water will be pushed out when you crank it with the spark plugs open. the oil not only helps corosion but re lubes the cylender walls for start up. im nost saying fill the cylender up with oil, just about a half a cap in each cylender, if that. the electronics are not sealed if water got inside. how do i know? well during francis my yard flooded, bad. and my moms nissan frontier's door didnt seal well enough and water filled in to the bottom of the dash (not the bottom of the level surface, just below the steering columb). the ECU was fully sumerged according to the insurance claims guy, thats why it was totaled. would turn over and fule pump would turn onbut it wouldnt start, no water even go into the engine, the exaust was spitten water like crazy but the intake didnt get a drop. explain that one...