5.7 Bravo Winterization

tpw99

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Jul 6, 2008
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I have a 5.7 357 Magnum 2012 Bravo. I'm located in a cold weather climate and I store it on a lift for the winter. In the past I've always had the marina come over each year and do the engine winterization but the marina recently closed so I'm probably going to do it myself this year. I have always winterized the water & head system myself in the past but since the engine was under warranty I wanted the let the marina do it. So I read the manual which came the re-maunufactured engine and it said the engine is a 3 point manual drain system. Remove the 3 blue plugs; 1 on the bottom port front and 2 on the starboard side in the raw water pump. It says to a. make sure boat is level b. let drain completely for a while while you do other work c. And, if you want, replace plugs and fill with anti-freeze. ( assume you do that by taking the hoses off in the upper front and pouring in fluid) I guess my question is: IS THAT IT?? It's all about the 3 blue plugs?? It also tells me to check all drain holes in outdrive to make sure they are clear.
 

DeepBlue2010

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What type of cooling system you have, open or closed (in other words, raw water or antifreez)? Manuals has - sometimes - generic instructions for different configuration of motors which may or may not apply to you. If you don't know the answer for this question, just post an overall picture of your engine
 

Starcraft5834

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IS THAT IT?? It's all about the 3 blue plugs??. = yup..

raw water cooled Mercruisers, whether its a 3.0 like mine or 5.7, or any other is all about removing the water from the block and manifold. drain it.. as Bondo says' "air don't freeze". drain your outdrive oil and replace that too. treat your gas.. let is sleep all winter EMPTY. don't waste your time with antifreeze which by the way can freeze.. air wont
 
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DeepBlue2010

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No, that is not it.

You need to drain the exhaust manifolds as well or it will crack if frozen. You have a Bravo drive so your raw water pump is on the engine itself. Remove the upper hose (the inlet hose from the transom) and the lower hose (to the oil cooler if equibed) and drain the water by pushing them as low as you can in the bilge.

Your engine is 350 mag and very recent year, check the manual and see if you have air activated drain system. basically a hand pump to push air inside the blocj and drain the system out. If not, make sure you insert a small wire or screw drive inside the hols to get them to open and drain. Sometimes debries build up and prevent water from draining.



While air sure doesn't freez, corrosion doesn't stop either. The correct mix of non corrosive antifreez could help preventing the engine from inside but this is just my opinion. If you want leave the block without antifreez, I would give it a good flush with Salt Away before winterizing. I do this anyway eventhough I have a fully closed system but I am a pain in my own az.


Our experts on the site (Bono, AllDodge, Chris, and multiple others) probably forgot about engine mechanics and correct procedures more than I will ever learn. So if any of them tells you differently, ignore what I am saying and follow thier advice.
 
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alldodge

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I have a 5.7 357 Magnum 2012 Bravo. I'm located in a cold weather climate and I store it on a lift for the winter. In the past I've always had the marina come over each year and do the engine winterization but the marina recently closed so I'm probably going to do it myself this year. I have always winterized the water & head system myself in the past but since the engine was under warranty I wanted the let the marina do it. So I read the manual which came the re-maunufactured engine and it said the engine is a 3 point manual drain system. Remove the 3 blue plugs; 1 on the bottom port front and 2 on the starboard side in the raw water pump. It says to a. make sure boat is level b. let drain completely for a while while you do other work c. And, if you want, replace plugs and fill with anti-freeze. ( assume you do that by taking the hoses off in the upper front and pouring in fluid) I guess my question is: IS THAT IT?? It's all about the 3 blue plugs?? It also tells me to check all drain holes in outdrive to make sure they are clear.

:welcome: back tpw99, been a long time no hear from, how ya been, don't be gone so long next time :D

Change your oil

The part that gives me concern is your 3-point drain system. If they work correctly, then easy peasy, but if they don't then there could be problems in the spring. The issue is all those different drain hoses and how they come together. Each one of those fittings can cause some issues. The problems with these are just starting to show up, guessing because they have been out long enough for sand and dirt to start causing issues.

The 7-point systems are real easy to make sure all water comes out. So for your question: You shouldn't need to bother with your power steering cooler because its on top the flywheel and water will drain to lower point. Pull the plugs and after she drains put a wire up inside the holes and see if anymore comes out. Next pull the hoses leading to the block from item 9 in ink below. Blow some air up those lines, not a lot but then see if more water comes out.
http://www.mercruiserparts.com/Show...ooling+System+(Bravo),+Air,+3+&+7+Point+Drain

Next pull hoses off bottom of exhaust manifolds item 3. Look for any hose which might be high and move it around to make sure it drains. If all this goes good you should be fine. Store the drive in the down position or as close as full down as you can.

If you want to fill with antifreeze, your boat, your choice, same goes with any of the other stuff out there being advertised to take some of your money
 

tpw99

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Jul 6, 2008
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7
How do I drain the manifolds? Is that from draining the hoses you are refering to? I don't think I have an oil cooler so we are talking one hose.
My motor does not have the pump. It is the manual 3 point drain system. Do I need to worry about taking out the thermostat at all?
Thanks!
 

alldodge

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You should have power steering oil cooler unless yours is an inboard. If it is an inboard and have full hydraulic steering, there will just be a tube where the power steering cooler would be. Don't bother with the Thermostat

3 point drain.jpg
 

thumpar

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Jun 21, 2007
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After an oil change I remove the plugs, the hoses from the seawater pump and the big hose off the circulation pump. Once drained I pull the lanyard switch to off and kick the motor over for half a second to make sure the water in the pumps is kicked out. Mine is a little older so I have the brass plugs at the bottom of the block. It is the same concept though.
 
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