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Winterizing 1998 7.4 L

J

jeffnoank

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I'm located in CT, with 7.4 MPI 1998 boat, Bravo 1 drive, water intake through Bravo 1, Salt Water Cooled. I have winterized fresh water cooled inboards beofre but this setup is new to me. Can anyone point to or provide clear instructions how to winterize a salt water cooled engine like mine ?
 
Re: Winterizing

When you say salt water vs fresh water the only difference is the salt............

YOU MUST BE MORE SPECIFIC!!

Do you mean fresh water cooled ( raw water) vs closed cooling ( heat exchanger and anti freeze) as part of the cooling system?

Need to know EXACTLY what you have..................
 
Re: Winterizing

No difference between salt/fresh water cooled winterizing except giving the engine a good fresh water flush. Use an antifreeze that prohibits internal corrosion. I would flush the engine after every use or install a salt neutralizing system.
 
Re: Winterizing

1. Run the engine on the garden hose until it's up to normal operating temp (t-stat open).

2. Either fog the engine till it dies then drain it completely... all draincocks open, making sure none are clogged (might have to stick a coat hanger up there to clear blockage) and leave open.
-or-
Get a few gallons of the environmentally safe/non-toxic AF (See West Marine). Get a container that you can attach to the water inlet ports through a hose and place above the outdrive. An isolation valve is handy to have too. Dump the AF into the container. Open the isolation valve. Start the engine. When you see the AF coming out of the exhaust & idle ports, fog the engine till it dies.

Generally, leaving it in lay up with AF is better for prohibiting corrosion, but runs a small risk of freezing if there are any pockets of low flow that don't get much AF.
If your area is prone to hard freezes for extended periods, I would leave it empty. Corrosion rate is very slow when the temperature is low.

One other note, with an engine that size, you may not be able to put enough fogger in it to kill it. I couldn't stop my 5.7L squirting 2 cans of the stuff in at the same time. Once it starts coughing and smoking, you can shut it off and rest assured it's fogged OK.
 
Re: Winterizing

I do all of the draining as above and then fill the block by pouring A/F thru the large water hose that goes to the circulating pump. Drain the large hose first by bending it downward. I use 1/2 gallon in that hose. Next I disconnect each hose at the T'stat and pour in about a quart thru each hose making sure A/F comes out of the exhaust on the OD. All of this work is done after fogging the engine.
 
Re: Winterizing

Thanks for the info, one last question, where are the drains you mention to located on this engine ? if there's a link online somewhere showing the locatiions in pic form that would be great. Hopefully no buried under the engine, this is a tight fit sterndrive, little accces to bottom of engine
 
Re: Winterizing

The boat US site suggested one option is to remove the therostat and then run AF through the outdrive via Muffs, this way the antifreeze will circulate through the entire motor
 
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