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DarkMantle

Winterizing a 496

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This is the first year I'll be in an unheated storage facility so I want to make sure I get this right.  I have the closed or at least semi closed cooling system with the Merc central drain system.  I assume the antifreeze which I think is the dextron type for the engine is good for the winter.  I want to confirm that I just use the air pump to dump the water out of the left and right side, hook up the muffs and flush with clean water for a bit, then just run straight antifreeze through it?  I'll be pulling the drive once all that's done.  Do you have to run on water for a while until the thermostat opens?

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When the shop does mine, they just run antifreeze threw it. It takes a while for it to get threw the heat exchanger. The air inlet on the heat exchanger blows out the two little lines to the impeller housing.

 

 

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5 hours ago, DarkMantle said:

This is the first year I'll be in an unheated storage facility so I want to make sure I get this right.  I have the closed or at least semi closed cooling system with the Merc central drain system.  I assume the antifreeze which I think is the dextron type for the engine is good for the winter.  I want to confirm that I just use the air pump to dump the water out of the left and right side, hook up the muffs and flush with clean water for a bit, then just run straight antifreeze through it?  I'll be pulling the drive once all that's done.  Do you have to run on water for a while until the thermostat opens?

You have a closed system that is more like your car. So the T-stat is on the heat exchanger side. Meaning, its in the flow of the AF not the raw water. So, "no".

What I would do, and thats me. Buy one of those winterizing kits that you can hook up to muffs or some engine like Volvos have a hose. https://www.defender.com/product3.jsp?name=camco-do-it-yourself-engine-winterizing-kit&path=-1|2285701|2285713&id=15648

Just fill it with AF, run it though the engine until it comes out the exhaust. It takes about 30 seconds and your done.  I don't open anything up to let air out, but opening anything will stop the pump from sucking up the AF. Unless I am missing something?? I have done this for years with no problems. Your pushing the water out and leaving AF behind.

I would leave the AF in the engine. The other train of thought is, that AF will slow down the rust from forming. So your removing the air.  

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Did my 496 and a friends for a decade now. Pump up drain to purge water. Release pressure so drains close. Run on antifreeze until it comes out the exhaust.  Done.

i use a submersible pump in a five gallon bucket and connect the pump outlet to the muffs with a 5’ hose. Perfect system.

496 will take almost 5 gallons pink to fill the raw water side.

As far as the engine coolant, get a tester and verify it is good to whatever temperature you expect the coldest day to be. You can draw it out of the resevoir.

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On 10/7/2018 at 10:47 AM, DarkMantle said:

 Do you have to run on water for a while until the thermostat opens?

No,  no need to wait for engine thermostat to open, as the antifreeze only  goes threw the heat exchanger, then out.

 

 

.

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Martin, question: i use a proper and tested fogging mix but what i find curious is that smoke from exhaust only appears to come out when the engine is up to normal running temp. Initially i thought the new mixture takes THAT long to reach to cylinders (old non-mixed gas in the fuel pump/system, etc) but today when i winterized, i had the engine up to temp first time (smoke showed up only when engine was hot), and then i ran it again on AF instead of water and once again, smoke only appeared 3-4 minutes into it, not immediately, even though i did not disconnect the external tank during both runs so the new gas would be well in the system from the get-go. 

not a major issue, but i was just very curious. do you have a clue why? smoke only comes out when engine is hot?? some chemistry stuff here or what?

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7 hours ago, yogi799 said:

Martin, question: i use a proper and tested fogging mix but what i find curious is that smoke from exhaust only appears to come out when the engine is up to normal running temp. Initially i thought the new mixture takes THAT long to reach to cylinders (old non-mixed gas in the fuel pump/system, etc) but today when i winterized, i had the engine up to temp first time (smoke showed up only when engine was hot), and then i ran it again on AF instead of water and once again, smoke only appeared 3-4 minutes into it, not immediately, even though i did not disconnect the external tank during both runs so the new gas would be well in the system from the get-go. 

not a major issue, but i was just very curious. do you have a clue why? smoke only comes out when engine is hot?? some chemistry stuff here or what?

I get water vapor once she is up to temperature, but the only way I know that the fog oil has reached the injectors is from the degradation in idle quality, and a pronounced exhaust odor. It takes quite a while at idle for the fuel in the module to be displaced by the fog oil. At least 20 minutes, and around a half a gallon gone from the fog tank. I let her run until the gallon is almost gone, then change the fluids, drain the raw water system, and hook the muffs up to the Marine/RV tank. I then run her long enough to re-establish oil pressure and suck down about 4-1/2 gallons of antifreeze (about 12 seconds). Just don't let the raw water pump run empty. While all this is going on, I'm pumping out the remaining fuel from the boat's tank, as I store it dry until spring. Next year, fill her up and enjoy the summer. I only change the fuel filter after a first outing so I'm not installing the new filter into a bath of fog oil.  W

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Holy crap, 20 minutes? I have the cool fuel filter module. #%^$&%$, I probably had mine running for a total of 10-15 minutes, but not 20 for sure. Have i NOT been fogging my cylinders all these years??? I though the smoke was the sign of the 2 cycle oil finally reaching the cylinders and burning. Crap. I can't tell how much fuel i've burned because my stupid external tank does not show a measuring scale/window, but even the manual says keep it running for 5 minutes at 1300 RPM so I presume they've measured the exact time when the mixture reaches the entire system , no?  Maybe me running it at 1300 speeds up the process considerably and I am ok?

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Work backwards. 496 burns approximately 3.6GPH at 1300 rpm so 460 ounces per hour. That is 38 ounces in 5 minutes, or more than a quart every 5 minutes. As long as your fuel line from the temporary tank is not too long, you absolutely empty a cool fuel canister and are burning the cocktail in 5 minutes.

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3.6GPH at 1300 rpm loaded or unloaded?  Mine will idle for 40 minutes on a gallon. W

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Good point, the document does not say. At 40 minutes per gallon at idle, that is still a pint every 5 minutes. Spin up to high idle and that would still clear a cool fuel module which appears to be less than a pint every 5 minutes.

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