Salt or Freshwater Does it matter?

[gunplumber7]

Recently obtained a 1974 Ebbtide boat which I am helping my friend convert to a bass boat. The boat came with a 1979 Chrysler 45 HP 457H9K. Upon looking at the boat and engine section here I see that this motor is listed as a salt water model. Can a motor made for salt water be used in fresh water too? I'm guessing that you wouldn't want to take a fresh water motor into salt water due to corrosion, but what is the actual difference? Thanks. Hoping to be bass fishin in the spring.

 

[john from md]

Re: Salt or Freshwater Does it matter?

An engine made for saltwater will work in fresh water. Make sure you change the water pump, fuel pump diapram and lower oil if you don't know when they were last changed.

John

 

[RRitt]

Re: Salt or Freshwater Does it matter?

It isn't the salt that hurts your engine as much as the electrical conductivity of the water. Every metal has a built in reactivity (i think the actual word is noble). If you have two different metals and put them in a conductive water then electrons from one will automatically start drifting to the other metal. The softer metal gets eaten up with corrosion while the harder metal is protected. It's a battery!

Ideally - a saltwater engine would all be made from the same metal so that there was no battery reaction. But more realistically you can minimize the uneccessary use of stainless steel, apply higher grade paint to exposed stainless, and install a larger sacrificial anode. The sacrificial anode is even softer than aluminum and acts as a protective shield for it.

and yes - this means that using your engine in polluted, brackish, or acidic water can be just as bad as saltwater.