Rippem

I did a search and didn't really come up with the definitive info I'm looking for. 496 H.O./O.K....so the block and heads are closed cooled and have anti-freeze in them. So I'm thinking the heat exchanger, seawater pump, coolers, and exhaust need to be drained of FW..correct? Am I missing anything? Is there a blue scew in butterfly plug everywhere that should be drained? We never put antifreeze in anything on the last 2 Gen(s) engines, just made certian they were dry and fogged. Is there any part of the FW circ system on these new motors that are questionable that you get all the water out? If you do the 496's yourself...what's your routine? Thanks.

Eternal Warrior

As far as the fresh water system goes, just use the little hand pump that comes with the engine to flush it. Change the oil, change the outdrive fluid, fog the engine, put stabilizer in the fuel. I think that's it.

Rippem

I've heard not to trust the hand pump to push all the water out? Extended periods of 20+ below zero are not uncommon here. How the hell do you fog F.I. engines? I always just fogged 'em thru the carb...no more! That was nice 'cause you got the top end, not just the cylinders. More help please.

Eternal Warrior

I hadn't heard that about the hand pump. I need to get all the water out as well. As far as fogging goes, there are some threads that talk about it for the F.I. engines do a search and your questions should be answered.

Eternal Warrior

I wouldn't think so. If the hand pump doesn't get all the water out there should be some drain plugs that will finish the job, but I haven't looked at my manual to confirm that.

Wally

iTrader: (1)

OK guys.....when you have a closed cooling system on a boat you still need to follow the same (more or less) procedures as if it were an open system. Granted you dont much have to worry about the engine itself with anti-freeze because its allready got it. But the main concerns are the external parts that are crucial to the engine. Like the sea-water pump, power steering cooler, Oil cooler and the exhaust risers. there are easy ways of doing it i'm sure but i think the easiest would be to just run the engine with a anti-freeze mix till it come out the exhaust. Since you dont have to worry about the thermostat opening you can bypass the whole warming up procedure....but it would be helpfull for changing oil so all the contaminates are suspended in the oil and not sitting ont he bottom of the oil pan waiting for next season!
Go to my Thread on "WINTERIZING-The full way" and in a few days i will have step by step pics on doing a full winterization on twin 500EFI's

HOUSTONPROP

Just bring your boat to Houston And I will be glad to keep the motor flushed all winter!

Darin

Kentz

Yes, that is it, that is exactly how the manual tells you to do it. Only if the pressure system fails, do you need to resort to manual draining. This will be my 4th winter following the manual. That is one of the main sale points merc used when introduced in 01. Leave the system pressurized, "indicators out" all winter.

Fog - 50/50 mix into fuel filter, disconnect fuel line, run until it stalls, have beer