Re: newbie-Mercruiser 4.3 winterizing issue - hoses need pulled?
Hi Folks: Wondered if taking out the three blue drain plugs on the boat is enough to get safely home or do I need to undue hoses? My Merc Manual simply shows taking out the three (3) blue plugs to drain the water. That's no
biggee up at the lake but where we want to possibly fish more before winter I wondered if any of you know if the manual is a bit weak on the issue of removing the water. Am I missing something? I don't want to freeze and crack this thing. THEN, when I do give it up for the winter do I need to use anti freeze? The manual doesn't say so. I'm just new to this engine. (and not super mechanical) Thanks for your help.
To just drain the water it is simple as the drain plugs, you have one high up on the T'stat housing, also one high that looks like a round hose valve you would have on your house, then one low at the bottom straight down from the round valve handle. turning that round valve will drain it all out, open the blue plug on the top left that is in the tstat housing, that will vent the system allowing it to drain properly, that round blue handle drains through a tube at the bottom just below another drain plug so that is the lowest point, and all hoses are supposed to drain to that, I do pull that lower plug also though, just to be sure. I also then crank my motor over, keep the kill switch off so it doesn't start, and you don't need much, just a short crank to purge any water from the water pump.
Look in your manual, page 104, just above "Preparing Power Package for Storage" you will see a note:
IMPORTANT Mercury MerCruiser requires that propylene glycol antifreeze, mixed to the manufacturers instructions, be used in the seawater section of the cooling system for freezing temperatures or extended storage. Make sure that the propylene glycol antifreeze contains a rust inhibitor and is recommended for use in marine engines. Be certain to follow the propylene glycol manufacturer's recommendations.
Pull off the larger hose on the tstat housing, its kind of a bear to break loose and there isn't much room to pull it straight off because it hits the alternator, but it will go, pour the antifreeze down that hose until you see it come out of the tstat housing. I then put the hose back on, and opened the drain plug on that housing, and using a funnel and a small tube, I added more through the plug hole until the funnel didn't take anymore then quickly pulled the hose and put the plug in, I am sure that was overkill but....
That single point drain is really a great idea, but if they "suggest" you put in antifreeze, why didn't they put a plug at the highest point that you could funnel some in with instead of pulling hoses off.......oh well....
Also.....damage from freezing is not covered by warranty, so if you aren't sure.........pay the pro's cuz I'm not one of them
Here is a pic of my 220 Mercruiser 4.3L MPI Alpha Catalyst in my hurricane SDS. Big circle is the main single point drain, small circle is the drain plug you remove right after opening the drain to vent the system, manual says it must be removed within 30 seconds of opening the drain valve to properly drain the system. Horizontal arrow points to the hose you remove and pour antifreeze down, vertical arrow just shows where the other drain plug is down below.
