PSA on Winterization Antifreeze

[Lou C]

I would love to have seen a study about whether filling cast iron engines with AF actually reduces corrosion or if it does nothing. We do spray oil pans, timing covers & leaf springs with Corrosion X or similar & that works. And Mercruiser has been recommending it for a long time in their manuals. I do it because of my 100% salt water use.

 

[QuietPriority]

Surprisingly enough in Ontario where we can get a cold stretches into the -30C range most marina’s still use a -50F pink PG. Blows my mind. Any water left behind and you can be in trouble with the dilution. Not to mention freeze vs burst ratings.

My last boat had a volvo 5.0 which I drained and filled with -100 Starbrite for the last 6 years with no issues.

 

[Lou C]

Even West Marine says to use -100 for those temps! I guess the marinas are counting on the thought that the -60 gets firm but doesn’t expand. IMHO that might be ok for plastic pipe but not for a cast iron engine!

 

[tpenfield]

I went to 'full closed cooling' systems on my I/O (sterndrive) boats about 11 years ago, and have never looked back. I just make sure the engine coolant is up to snuff and run -100˚ F antifreeze through the raw water side. Done.

Since I'm in salt water, I also run a De-Scaler solution through the raw water side before winterizing.

 

[tpenfield]

Surprisingly enough in Ontario where we can get a cold stretches into the -30C range most marina’s still use a -50F pink PG. Blows my mind. Any water left behind and you can be in trouble with the dilution. Not to mention freeze vs burst ratings.

Yes, most folks do not understand the path which the water/anti-freeze flows through their engine. So, they mistake seeing the anti-freeze come out from the outdrive as having thoroughly saturated the engine.

Then there is the whole freeze point vs. burst rating aspect. Lots of folks see the "-50 F" on the label and think the AF stays liquid until then.

 

[Scott Danforth]

I moved to Florida...... would like to say we don't need to deal with winterization. luckily I only need to drain the raw-water side.

 

[tpenfield]

I moved to Florida...... would like to say we don't need to deal with winterization. luckily I only need to drain the raw-water side.

Yes, the Florida folks are pretty much exempt from winterization. The Texas folks . . . not so much . . . at least recently

 

[Lou C]

How to Choose Antifreeze for Your Boat Engine | West Marine

Visit West Marine to learn about freeze protection, burst protection and why propylene glycol-based antifreeze is the best choice for your boat engine.

www.westmarine.com

 

[Scott Danforth]

Yes, the Florida folks are pretty much exempt from winterization. The Texas folks . . . not so much . . . at least recently

it still gets below freezing, even in cities like Frostproof.

I had ice in the bird bath this past winter as it got down in the teens.