Flushing freshwater through engine from dock hose? 3.0L Mercruiser

enginesilo

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So last year I used to trailer my boat and flushed it after every use on the hose for a while. This year I am keeping the boat in the water. I've seen the closed cooling systems and am considering one. Are they hard to install?

If I just keep it plain jane raw water cooling, is there a kit I can buy that will let me hook up a hose to run freshwater through the engine from the hose? I've read how people put some type of T fitting, or a special connector so you can run the fresh water hose at the dock through the engine. Anyone know about this, and what is needed to rig this up?
 

haulnazz15

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Re: Flushing freshwater through engine from dock hose? 3.0L Mercruiser

The major issue is that you can't run your engine out of the water without the drive being in the water or at least on muffs you would burn up the outdrive impeller. You should just get a pair of muffs (assuming your boat is on a lift) and run it that way if you feel the need to flush it out. I assume you are running in saltwater?
 

enginesilo

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Re: Flushing freshwater through engine from dock hose? 3.0L Mercruiser

I am keeping the boat at a boat slip in the salt water, so the drive won't be able to come out of the water. I've heard of people putting some type of T-valve in the water supply line and running the hose to flush out the raw cooling system. Anyone know of this and what I need to set it up?
 

enginesilo

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Re: Flushing freshwater through engine from dock hose? 3.0L Mercruiser

There are kits, as you have seen, that allow you to flush the engine but... they do not flush the ourdrive and that is not good. If it were me I would simply tilt the drive up, put muffs on it and run the engine for a few minutes at idle. That way you are spinning the raw water pump in the drive and flushing the entire cooling system of the drive and engine.

Think i'd be able to reach over and get the muffs on while in the water? Seems like that may be hard without actually getting in the water.
 

bruceb58

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Re: Flushing freshwater through engine from dock hose? 3.0L Mercruiser

Its not as critical to flush the drive every time becuase the drive siits completely in water. Its the areas where you have a combo of air and water that is the problem.

I put a neutra salt system on my boat but that system only works on engines that have engine mounted raw water pumps. The systems that you posted in your second post seem like pretty good alternatives to me. The question is will you be religious about using it every time.
 

enginesilo

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Re: Flushing freshwater through engine from dock hose? 3.0L Mercruiser

Can the Neutra Salt System go on a Mercruiser? I remember seeing those in the boats that had the same engine branded as a Volvo. I called and asked a random company who was selling one and they said NO.

Did more looking around and that SuperFlush system is looking really promising. For $249 I might have to get it for the peace of mind knowing I am at least getting tons of fresh water inside.
 

enginesilo

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Re: Flushing freshwater through engine from dock hose? 3.0L Mercruiser

Back to the boat this season. Anyone recommend a good flushing system so I can flush the engine when in the water?
 

cooter2506

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Re: Flushing freshwater through engine from dock hose? 3.0L Mercruiser

what about the SuperFlush you found last year?
 

Philster

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Re: Flushing freshwater through engine from dock hose? 3.0L Mercruiser

I looked into this: Not everything is flushed. The cool water hits the thermostat and it closes, thus only a small portion of the motor/etc is getting flushed.

Hope I am wrong.
 

enginesilo

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Re: Flushing freshwater through engine from dock hose? 3.0L Mercruiser

After researching last year I learned that most systems do not flush everything. I've talked to a lot of people who have had I/O's and they say they haven't flushed them till the end of the season and have lasted well over 10+ years in the water.

I've seen engines with rusted out risers and stuff when I was shopping so I'm guessing those people did a crappy job of flushing, but with salt water it is inevitable.

Anyone have a system that they've used for many years with success?
 

Bondo

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Re: Flushing freshwater through engine from dock hose? 3.0L Mercruiser

Can the Neutra Salt System go on a Mercruiser? I remember seeing those in the boats that had the same engine branded as a Volvo.

Ayuh,... Could you get alittle more specific as to just What Mercruiser you're talkin' about,..??
 
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