I am in Seattle and am laying up the boat until April. Sea Ray with 496Mag.
I have pumped out the water out of the heat exchanger using the hand pump and put fuel stabilizer in the tank.

How important is fogging the engine?? If I dont do it, is it totally critical?

Thanks,

YES, you do want to do 'fog' the 496

First, pumping out the sea-water is not good enough. Even though the manual and many folks say its all good; I trust my mechanic and run antifreeze out of the motor. There are pockets of water in the system that the air system will not get out. The manual also states that you need to remove the ends of the heat exchanger to get all of the water out. However, the oil cooler still has some water in pockets as well; that will not drain with the air pump system or by pulling the blue freeze plugs. Its MUCH MUCH MUCH better to be safe, rather than sorry in the spring. Also, if you have merely air in your system, you are actually promoting rust. Keeping the surfaces wet with antifreeze, especially an antifreeze with rust inhibitor is the best way.

Second, fogging is very important. You CANNOT spray fogging oil into the throttle body. Don't even think about it. You need to remove the fuel/water separator/filter, pour out 1/2 of the gasoline, and fill the now empty half with 2 cycle oil. This is the only way to properly fog the 496 (or any EFI for that matter).

The small amounts of fuel left in the fuel rails, injectors, lines, and such are MORE susceptible to gelling over the winter than the fuel in the tank, so having stabilized fuel as the last fuel run through the engine is very important too. Having this last bit of fuel run through to be half/half fuel/2 cycle oil is also better for the system.


No offense, but don't half-ass your winterization. You will pay for it BIG time in the spring if something gets FUBAR.

I have a pair of 496HOs, and I live in VA. I am fairly certain you will be colder this winter than I will, and I have already done the above as described.

Wally made an ALL ENCOMPASSING winterization checklist some time back. Do a search. It is full of priceless information.

I also use an oil additive that enables the oil to stick to the internals of the engine, to promote better lubrication in spring as well: Lucas Oil Treatment. Its worth the investment; about $9-15/quart.

Merc recommends a 12:1 gas/ 2 stroke oil mix (not a half and half mix) with some stabilizer added run through the engine either from a remote fuel tank or the water seperator methods works too. Make sure you kill the engine before you start drawing pure gas again or unhook/turn off the main fuel tank. Every mechanic lovesss anti freeze so they can charge you to do the work, you don't need it.

Thank you for the valuable information.
I need to spend the time and money and put it away for the winter correctly. It is a new motor so this is the 1st season.

If the engine is full of a antifreeze mixture I assume it would reduce a dry start on the impeller in the spring as well.

There are so many Lucas Oil products- which one do you use for your 496?

Thanks again for the data- I really appreciate it.
R-

Your only dumping half the fuel out of the filter, and putting in some 2-stroke, by the time the system re-pressurizes and mixes with all the fuel it's not really 1:1... If you were mixing it up and running it in a 5 gallon can then yes, measure out the appropriate amount for 12:1...

I use Mobil1 15w50 Synthetic, so I buy the Lucas Oil Synthetic additive. It comes in a pointy 1-quart bottle with a black label OR in by the gallon. ( OldSchool says the bottle has many uses once finished. )

The label says to mix it as 20-25% of your entire oil capacity, but I only go with 1 quart of Lucas to 7 quarts of Mobil 1 per my mechanic's instructions. I did this on my HP500EFI and my 496HOs. I cut open my oil filters on occasion and they are in perfect condition.

i remove the fuel line from the fuel filter replace filter and run the mix that way but i have been told that going there the fuel/water seperature is one way of doing it to.

You'll burn that gas out of your fuel filter in a heartbeat, I use an outboard gas can, connect it to the intake of the fuel filter and let it burn for a while. The merc trained master mechanics at my marina use a 5:1 ratio of Merc two stroke oil in the gas can. Antifreeze (pink stuff) like everybody else says. You won't burn your impeller next spring if your start it up on the hose.

that the way. i forgot to mention the gas can and 5:1 is what i was told as well.

does anyone else pull the plugs and spray fogging oil in the cylinders