Hummingbird Piranha Max 320

A few months back I bought a Humminbird PiranhaMAX 230 Portable. I got it soaked in the salt but make sure to wash with freshwater. Yesterday I noticed the power pin completely rusted through and is lodged in the fishfinder's power plug. 

It is a really good idea, a good FF powered by 8 AA's in a waterproof package but it doesn't seem to like the salt...

Dielectric grease is your friend. 

Don't be shy with it either.

So greasing the terminals with that kind of grease works?

Micah,
as Insayn said above, Dielectric silicone grease is what you need. you can pick it up at your local electrical supply store. it's designed specifically to prevent your problem, yet allow conductivity/ connectivity.

Thanks for the tips, I will be purchasing some of that dielectric grease and will use that in my next FF.

I gooped that pig snot (dielectric grease) on my Cuda 250 terminals 3 years ago and it has seen many salt water dunks since. 
No corrosion anywhere.

Still give it solid rinse in fresh water though, and touch back up with dielectric grease.