Blowing Out the Cooling System

[Budman]

Has anyone had much success with some of the newer products that you screw onto your fresh water cleanout and then use compressed air to flush all the water out of your cooling system? Seems to me that it would flush "most" of the water out, but perhaps not all.

Could you use one of these adaptors (to get most of the water out), and then add RV antifreeze through the fresh water clean out to ensure against freezing?

I do not have a trailer. The boat sits on a Sunstream Lift in the front of the house and therefore is rather difficult to work on (especially the outdrive).

Bud
2004 Cobalt 240
Volvo 8.1

[ajcampen]

not necessary, after you pull plugs, just fill with anti-freeze. you'll either want to circulate via the impeller or make sure you pour on both sides of the engine (before and after the thermostat) which I don't know how to do.

[jhnmdahl]

I've never blown it out or used antifreeze. Just pull the little blue plugs along each side of the engine and drain the hoses in front, and I'm done. I suppose different people like different things, and my method might be different if I had a closed cooling system, but I'm most comfortable seeing the last drops of water drip out before putting the cover on for the winter.

Others have made the good argument that refilling with antifreeze may inhibit rusting, but I haven't heard of anybody having a problem with it either.

John

[sailor55330]

Blowing out the system with pressurzied air is interesting. That's what they do with sprinkler systems and it seems to work fine.

I remember talking to various dealers when I had my last boat. Some did use Antifreeze, some didn't. Those that didn't used the line "air doesn't freeze". Those that did said "there could always be a little bit of water in a low spot". Interestingly enough, my old VP manual didn't call for the use of antifreeze--just drain it. I always used antifreeze when I did my own. I used to be able to get -100F at my local West Marine, but now they only stock -50, which is recommended for 14-18F. After that it started to slush, which isn't very comforting knowing that the winters here can easily get to -25/-30 air temp. Now that I have the dealer do it, I don't honestly know what they do. I just keep the receipt and if there's an issue, it's on them.

[AsLan7]

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We blow our line out with the included Merc pump and then fill with RV Antifreeze (via Muffs) to keep the interior from rusting.
Easy and works great.

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Oh, and welcome aboard budman!

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