Winterizing a Merc A1-G1 Block Question Antifreeze

[1985 Century Mustang]

I'll be winterizing my boat in a few days, and focusing on the block right now.
Question, can I use regular antifreeze in the block, or do I need marine antifreeze?. After all it is a Chevy block. Your thoughts.

 

[Bondo]

Ayuh,....... I've been winterizing motors for decades,.... Drained, 'n dry,....

 

[1985 Century Mustang]

Ayuh,....... I've been winterizing motors for decades,.... Drained, 'n dry,....

So your draining the block dry and your not using antifreeze?
If so do you run the motor briefly without water, please elaborate. Can you post exactly how you do it? Thanks

 

[Candy Gramformongo]

I bought a '70's era Mercruiser 120 this year and just winterized it for the first time.

My understanding is that you can use automotive antifreeze. It just so happened that I did a drain and refill on three cars this year, and saved the old antifreeze. I have a lifetime's supply of boat winterizing antifreeze.

Also, at least for the 120, antifreeze is optional, but "recommended." Supposedly just the drain is adequate protection, but under the theory that you can never be too safe, you can also put in antifreeze.

 

[Bondo]

So your draining the block dry and your not using antifreeze?
If so do you run the motor briefly without water, please elaborate. Can you post exactly how you do it? Thanks

No,...... Pull the drain plugs, probe the holes with a pick to knock any crud outa the way, then when drained, put the drain plugs back in,....
Also, remove the bottom of the big hose, to drain any water hidden in the circulating water pump,....

 

[Scott Danforth]

we have a sticky.

Winterizing Inboard and I/O

Winterizing your engine and drive. Winterizing your boats engine and drive is a lot of work. Not doing it or doing it improperly WILL be very expensive to fix , and that is also a lot of work. Plan on giving yourself the full day to winterize your boat, and don't wait till the last minute to do...

forums.iboats.com

 

[Lou C]

If you're going to use AF, the way to do it is to use non-toxic Propylene Glycol with corrosion inhibitors. If you use toxic Ethylene Glycol that's going to be spilling all over your driveway when you start up in spring.

 

[Chris1956]

Gee, Lou, In the spring I used to drain the antifreeze back into it's original containers and save if for next season. I saw no reason to dispose of it each year.

 

[1985 Century Mustang]

@Bondo So if I remove all the water with the drain plugs and lower hose etc. This should be suffice. Could it hurt to add some antifreeze also?

 

[Bondo]

@Bondo So if I remove all the water with the drain plugs and lower hose etc. This should be suffice. Could it hurt to add some antifreeze also?

Ayuh,...... If yer into throwin' money away, go for it,.....

 

[Lou C]

Gee, Lou, In the spring I used to drain the antifreeze back into it's original containers and save if for next season. I saw no reason to dispose of it each year.

You can though it might be mixed in with some dingy bilge water and motor oil drips lol.
Might try it next spring. clean bilge out, drain then put plug in drain af, then remove plug and put AF back in containers.

 

[1985 Century Mustang]

Ayuh,...... If yer into throwin' money away, go for it,.....

I have a gallon of new AF from last year unused. I'll throw it in.

 

[DeepCMark58A]

I prefer to pickle my motor, automotive antifreeze also has corrosion inhibitors.

 

[Lou C]

So does West Marine (-100 burst protection, -50 freeze protection) and Sierra PG automotive antifreeze which you can mix up to whatever strength you need, I mix mine to -30*F.
both non-toxic & both have corrosion inhibitors.
BTW I have done this each winter for 20 years, boat is used 100% in salt water, sits on a salt water mooring all season May to Nov. So far the block and intake manifold have not rusted through. I replaced the cyl heads but that was mostly because of overheat damage. Now you freshwater guys don't have to worry about this but here in the salt pond, the engine and exhaust gets filled with PG antifreeze and the trailer gets sprayed with Corrosion X on all the fasteners, springs, etc. I think it works, it has for me.
So do what you think is needed in your environment. I know what works in mine....

 

[Chris1956]

Lou, 20 years is a long time for risers and exhaust manifolds to last in salt water. You might slide the rubber sleeves off the risers and have a look at the risers. That is where they tend to rust away first.