fresh water motor in salt water?

Question
Hey Richard, I have a 1989 fiberglass bass tracker 1800 F/S with the original '89 mercury 150hp XR4 motor with paralift. I would like to know if I can use this combination to do inshore (in marshes) shrimping. I've heard you can use a fresh water motor in salt water as long as you run fresh water through it soon afterwards. Is it possible to get my motor set up for running in salt water without fear of damage? I would appreciate any information you care to pass along to me.  

Answer
No problem!  I have owned and opperated various outboard engines in salt water for the last 40 years.  I have never owned a "salt water" model.  In fact, up until a few years back, there really was no differentiation between fresh or salt designated models offered by the major manufacturers.  If you look closely at what differentiates a "salt water" model from a "fresh water", you will see it is a matter of a few external parts that are more corrosion proof or where stailess steel replaces painted.  

If you hose down the engine with fresh water after each use and run fresh water through the cooling system, there is no reason why your engine should not continue to perform just as it has in fresh water.  And even if you are not able to do so after each use, it is very unlikely any harm would be done.  Though I trailer my boats and can always use fresh water after each trip, I only hose down the engine most of the time, and flush out the cooling system only after several trips.  I have never had a salt deposit problem in any of my engines.  Many of my friends who keep their boats in salt water throughout the season, usually hose down the outside of the engine and only flush the system at the end of the season.  I have not heard of any salt build up problems from them.

If you rinse and flush the engine after every trip, it is best.  But doing so every couple of trips, is good too.  And even if you wait and only do so occassionally, chances are things will be OK.  I am not advocating neglecting the fresh water flushing and rinsing, just letting you know that through my personal experience, it is not absolutely necessary to do so every time the engine is used.

-Rich