Not good. Maybe

scatgo

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I finally got to winterizing my outboard today and for the first few minutes i ran the engine a brownish sludge formed on top of the antifreeze in the catch pan I use. I ran the engine for about a half an hour and the amount of sludge did not increase but I am freaking out thinking it is engine oil leaking into the cooling system. I only got to use the boat for about 20 hours this summer and it ran great and the oil level on the dipstick looks like it is about the same as it was when i got the boat back in March. Can someone please help me figure out what is going on?sluge.jpg
 

airshot

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Why are you winterizing an outboard motor. ?? They are self draining unles this is something new to me.....?
 

scatgo

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then what is the pump and kiddy pool for?
I used the pump to feed antifreeze to the outdrive via a flusher. The plan was to make sure all fresh water was removed from the engine so it couldnt freeze up and damage the engine.
 

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Scott Danforth

Grumpy Vintage Moderator still playing with boats
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per the manual.

change engine oil and filter
drain the block and manifolds and hoses
you are now winterized

of you want to add antifreeze, use a funnel and introduce to the block/heads/manifolds via the hoses at the thermostat housing
 

Lou C

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Did you wait too long to winterize? Did it freeze before you got to do this?
The reason why that method is risky is that the thermostat functions as a gate valve; it is what allows raw water to leave the block. On a cool fall day often the stat won’t open long enough while the engine is idling on the water hose; it just doesn’t build enough heat with no load. The only way to safely use that method is to drain it first and if you’re going to do that you might as well just manually fill it via the hoses.
 
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matt167

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Because I’ve watched that very video. Your relying on a guess that the thermostat opens long enough to dilute the water in the block enough to prevent freezing. -50 antifreeze works on a 100% concentration only. 50/50 won’t make it -25. Follow the manuals and drain everything
Why would you say that?
 

Lou C

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I’d like to see people who do it that way take a sample from each block drain & then test it with a refractometer & see what you get….I’ll be surprised if you get adequate freeze protection.
 
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I flushed my block with the -50°F anti-freeze & checked the anti-freeze that came out. The water/anti-freeze solution froze in my freezer to a slush at +5°F. My boat is in my garage so I don't think it will get that cold.
 

Lou C

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Interesting…I think anyone who uses the suck up the AF method without draining should test what comes out of the block drains. It will show you if your AF is diluted because not all the raw water exited the block. Then you can decide if this method is too risky to continue doing it that way. And you won’t lose an engine! I think anyone using this method should not use -50 or -60 only -100….but manual drain & backfill is really the best way & is what Merc advises in their manuals…
 

jimmbo

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For 20 yrs, I have just drained the Block, the manifolds, the Big Hose between the Circulating Pump and the Stat Housing, pulled the Ignition Lanyard and cranked the engine to allow the Raw Water Pump to drain any water out of it and the Passages. Put the Engine Cover down, and tarped the Boat. Never had any issues
 

Scott06

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Why would you say that?
because generally these winterization videos with the camco or similar system dont show draining the water out first. While some of my neighbors in upstate NY have used this for years, I wouldn't trust it to fully get freeze protection through out the block. Obviously several ways to skin the cat but i prefer to drain, probe the holes, and backflush with a little AF to ensure any residual water is removed.

I would think what is in the pan is either oil that was in exhaust (new engine may not be fully seated yet or sediment out of water jacket, maybe some carbon if running rich ...
 

scatgo

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Interesting…I think anyone who uses the suck up the AF method without draining should test what comes out of the block drains. It will show you if your AF is diluted because not all the raw water exited the block. Then you can decide if this method is too risky to continue doing it that way. And you won’t lose an engine! I think anyone using this method should not use -50 or -60 only -100….but manual drain & backfill is really the best way & is what Merc advises in their manuals…
When I used the suck it up the outdrive method i did keep an eye on the temperature gauge to make sure it got up to normal operating temp to make sure the thermostat opened. After reading a few posts that suggested it was a bad way to do a winterize because the thermostat might not open i did exactly what you suggested. I pulled every hose off took a sample and they all tested down to zero degrees. The one mistake i did make was I didnt think to pull all of the hoses to drain all of the fresh water out so the AF did not get diluted. I did use standard automotive AF. If there was no water in the engine I would have had -34. Its a very rare occasion if we see 20 degrees around hear so Ill just keep a eye on the temp and if it looks like we might see 0 Ill deal with it. Thanks to you and everyone for the help. Happy Thanksgiving.
 
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tank1949

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Based on what I see, motor will need a tear down. Too much oil in slush. Do compression test first to see if only heads/gasket need replacing. Convert a junk yard 350 to marine. A lot cheaper.
 

tank1949

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I used the pump to feed antifreeze to the outdrive via a flusher. The plan was to make sure all fresh water was removed from the engine so it couldnt freeze up and damage the engine.
On Chevy blocks there is a pipe threaded plug on each side of block under heads. You can use a mirror to see it. I believe it is 3/8" NPT. It will drain excessive water not dumped out by hoses.
 
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