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Larry W4CSC
 
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Default Fresh-water flushing a raw water system?

On Mon, 26 Jan 2004 23:17:52 -0500, "Leanne" wrote:


When we were running the Volvo that was raw water cooled, there
was an attachment, in the water line inboard of the strainer that
allowed for flushing. About a quarter turn on the fresh water
hose was sufficient for enough cooling. It also worked when you
went to the hard for the winter as it was an easy way to get
antifreeze into the cooling system.

Leanne


If one were to introduce fresh water from the hose to a T after the
salt water strainer (with a valve in the fresh water inlet, of course,
to shut off when not flushing), many good things would happen at once.

You'd be providing fresh water in the intake of the engine water
pump.....flushing the engine.

You'd be BACKFLUSHING the intake system and strainer, probably blowing
out the crap in the strainer back overboard.

The backflushing of the intake with fresh water would eliminate any
"pressure" from the hose as the system would be wide open to the sea.
There wouldn't be any pressure to worry about.

In all honesty, this isn't my idea. My Mercury Sport Jet 175 in my
Sea Ray Sea Rayder F16XR2 is fresh water flushed this way. The only
difference is it has no water pump to buy impellers for. 35 PSI of
seawater pressurizes the water jacket from the BIG pump under the
stern. It simply has a pipe pointing into the 60 gallons per second
pressurized water stream just aft of the stator inside the nozzle's
pressure chamber.

There's no reason not to put a T with a ball valve to the fresh water
hose tap in the hose between the strainer and the water pump. I,
personally, like the idea of flushing out the salt in ANY cooling
system after use. Most yachtsmen, who are too lazy to eliminate the
water ingestion into their diesel tanks by filling them after use,
wouldn't flush the engine, either. To many, engines are just
disposables, anyway. The water jacket, all its fittings and the main
jet pump on "Tess Tickles Too", after 6 years of salt water use, look
just like the first day I launched it.....just because it's flushed
after each use before being stored. It's stupid to leave salt
corroding away the inside of an expensive diesel engine, eating away
at the zinc pencils, when you're not using it.....


Larry W4CSC

Is it just me or did the US and UK just capture 1/3
of the world's sweetest oil supply? What idiot wants to
GIVE IT BACK?!!