Re: cleaning salt off outboard motor
If you use wd-40, follow with a real lubricant/coating, such as silicone or white lithuim grease. WD40 removes water and leaves your metal like a salt magnet.
I wonder if there really is "salt" under the hood. I suspect you may be seeing an electrolysis corrosion. Salt air shouldn't result in salty crystals under the cowl--somehting I haven't seen in the dozens of motors I've run exclusively in salt for 40+ years.
However, once I left my key on, motor down, overnight in salt water, and the next day had a dead battery and a motor, especially the lower unit above the water line, looking like a sugar donut.