Another winterize question

[ricovw]

I used to have a 3.o merc I/O and winterizing was a breeze. I just drained the manifold and the heat exchanger and I was done.
Now I have a new boat with a 2000 Merc 4.3. From what I can gather, I have 2 ways to winterize.

1) AF method. I have a winterizing kit (Camco 65501). basically run the water for 10 mins to open the thermostat and then shut the water supply valve and open the AF valve and when I see pink AF coming out the exhaust shut the motor off and I'm done.

2) Air Don't Freeze Method - My 4.3, being a 2000 with heat exchanger has 5 drain plugs. Pull all 5 and drain the water, ensure the heat exchanger is empty on the sea water side, and done.

Anyone see any issue with either of these? Thanks in Advance!!

 

[Scott Danforth]

pull all 5 drain plugs and probe the drain plugs. then pull the hoses.

 

[todhunter]

Does a 350 SBC have 5 drain plugs too? I found 4 - one on each side of the block and one on each exhaust manifold. If it does have 5, where is the 5th?

 

[Mad Props]

Not a 5th plug, but you want to remove the water inlet hose from the transom... I usually do it at the power steering cooler... I also like to pull the large hose from the water pump... I usually don't get much, but it tends to act a little like a trap...

 

[ricovw]

Cool, thanks guys.

 

[Scott Danforth]

Does a 350 SBC have 5 drain plugs too? I found 4 - one on each side of the block and one on each exhaust manifold. If it does have 5, where is the 5th?

5 only on the V6

pull the hoses on a V6 or V8

 

[ricovw]

Thanks Scott for answering my questions. I will winterize this weekend.

 

[tpenfield]

Here are my comments to the #1 method you described . . .

 

[QBhoy]

Do it by the manual. Which is neither of your two original thoughts. Drain...then fill with AF.

 

[Boater31]

My 4.3, being a 2000 with heat exchanger has 5 drain plug.

If there is a heat exchanger isn't that Closed cooling and draining the block would drain EG antifreeze?

 

[ricovw]

If there is a heat exchanger isn't that Closed cooling and draining the block would drain EG antifreeze?

good Point.

 

[tpenfield]

Good point about the heat exchanger/closed cooling. Depending on if you have a 'half' system or a 'full' system, here are some diagrams . . .


.

.
Closed cooling is easy, since the flow through the 'open' side is more sequential than a raw water cooled engine, and there tends to be less water to purge. Full systems are easier to purge than half systems.

 

[nola mike]

Wow, @tpenfield , those are awesome diagrams. I daresay they're sticky worthy, @GA_Boater

 

[GA_Boater]

Good point about the heat exchanger/closed cooling. Depending on if you have a 'half' system or a 'full' system, here are some diagrams . . .

Full System
.
Half System
.
Closed cooling is easy, since the flow through the 'open' side is more sequential than a raw water cooled engine, and there tends to be less water to purge. Full systems are easier to purge than half systems.

Ted, you are now immortal It's in the Adults Only stickies for now and will be added to the rest of the stickies.

Wow, @tpenfield , those are awesome diagrams. I daresay they're sticky worthy, @GA_Boater

Thanks for the tickle, Mike.

Many stickies got fouled up when migrating to the new XenForo forum, so VB stuck it to us one more time. I put "Verified" at the end of working stickies or those I've fixed. It's gonna be a while. If any of you guys happen to run across a lost stickie, either PM a Mod or flag the post. Any and all help is greatly appreciated. Thanks, folks.

 

[Lou C]

You can use the Camco style kit if you have closed cooling as long as the flow is pressurized with a bilge pump or similar, it will fill the raw water side of the heat exchanger & exhaust system (manifolds + elbows if half system, elbows only if full system) with antifreeze, if you are in an area that gets down to or below zero I'd use -100 instead of -50 or -60.

Why you should NOT use the Camco kit with raw water cooling...with this system you are depending on the engine thermostat to open fully to allow the raw water in the block to exit the engine via the exhaust system. On a cool fall day, idling on the water hose this may not happen. So the only safe way to use this kit is to drain the engine first. If you're going to do that might as well forget the kit and just backfill with the right antifreeze. I'd done that for all the time I've had this boat but if I repower it I will add a half closed cooling system and use the tank with a pump to pressurize the flow.

 

[nola mike]

Seems like a huge waste to do anything on a full system. What are you protecting? Risers? Hx? Even a ½ system I really doubt you'll be extending manifold life significantly with a/f vs. just a fresh water flush.

 

[QBhoy]

Seems like a huge waste to do anything on a full system. What are you protecting? Risers? Hx? Even a ½ system I really doubt you'll be extending manifold life significantly with a/f vs. just a fresh water flush.

100% protects the block internals against cold corrosion, when filled with AF. No doubt about it.

 

[nola mike]

100% protects the block internals against cold corrosion, when filled with AF. No doubt about it.

The internals that are already bathed in antifreeze?

 

[Lou C]

Seems like a huge waste to do anything on a full system. What are you protecting? Risers? Hx? Even a ½ system I really doubt you'll be extending manifold life significantly with a/f vs. just a fresh water flush.

and that's the $64,000 question.....does it really protect cast iron? Apparently Merc thinks so because they either recommend or require that the seawater side of the cooling system be filled with marine antifreeze. Never seen a test of this though. I do know that if I keep spraying my trailer leaf springs with corrosion x or similar they last much longer....

 

[QBhoy]

and that's the $64,000 question.....does it really protect cast iron? Apparently Merc thinks so because they either recommend or require that the seawater side of the cooling system be filled with marine antifreeze. Never seen a test of this though. I do know that if I keep spraying my trailer leaf springs with corrosion x or similar they last much longer....

Just chemistry really. Reduce the oxygen and reduce the corrosion. No brainer for me. My boat has had this since new and not a sign of any flakes of rusted metal to block the drains.