Fresh Water Flush..Is it REALLY Necessary?

[SEEKER]

We've been boating every weekend now since the middle of April and the harbor we keep our new 25sc at has been under construction and no fresh water flushing facility has been available (boat is kept on trailer in boat yard) so I haven't been able to flush out my engine which I normally would do after each use in the salt. So I've been thinking how necessary is it really... ? My rationale is this; I have a Yanmar 150 Marine Engine that is designed to run in the salt, most of the time these engines never see fresh water especially if they are stored in the slip over the winter. Besides having to replace zincs more often is a fresh water flush going to significantly improve the life of my engine beyond it's normal hourly maintenance schedule?

Opinions? Thoughts? Comments?

 

[knotflying]

Your question has peaked my curiosity. I just bought an R-27, my first inboard. I always flushed my outboard after using it in salt water, but with my new inboard figured it wasn't possible or at best difficult to do. I would feel better if I could flush it, but perhaps that may be overkill. If you can do the flush can you explain how you would do it?

 

[SEEKER]

The flushing process is really easy, you do it just like you would when winterizing the boat...just pull off the cap and strainer from the sea water intake and put the end of your hose in there, crank the water and start up, obviously make sure you have water coming out of your exhausts. I ususally pull my drain plug to keep the excess water out of the bilge.

 

[rt11002003]

Those engines are fresh water cooled (FWC) using expensive ( 😱 ) Yanmar antifreeze. 😉 Flushing only affects the raw water system, primarily the heat exchanger with those tiny openings that will clog after awhile. Keep the heat exchanger clear and you won't bother the engine.

Gene

 

[thataway]

The other place where fresh water flushing may pay some dividends down the line is the exhaust manufold and raiser. These are areas which tend to corrode with time and the raw salt water cooling. However, I doubt that flushing or not flushing would make a lot of difference over a peroid of a couple of years.