Winterize 350 Mag

vans

Petty Officer 3rd Class
Joined
Sep 26, 2004
Messages
78
First time with this engine, Merc with 3 point drain system
Problem-It's to easy, I feel I must have missed something, I'm used to pulling plugs from block, pulling hoses etc.
I removed the four blue plugs like manual told me to do, had plenty of water come out, then reinstalled plugs, dumped a gallon of rv antifreeze down tstat housing, removed plugs again to check color-which was pink, reinstalled plugs and dumped 2 more gallons in it, as added protection

Lower unit-Bravo 3, used an old pump up garden sprayer to pump the 3+ quarts of lube in it. Worked like a champ!, my plastic screw in fitting and hose off my quart pump adapted easily to my sprayer.
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
70,465
First time with this engine, Merc with 3 point drain system
Problem-It's to easy, I feel I must have missed something, I'm used to pulling plugs from block, pulling hoses etc.
I removed the four blue plugs like manual told me to do, had plenty of water come out, then reinstalled plugs, dumped a gallon of rv antifreeze down tstat housing, removed plugs again to check color-which was pink, reinstalled plugs and dumped 2 more gallons in it, as added protection

Lower unit-Bravo 3, used an old pump up garden sprayer to pump the 3+ quarts of lube in it. Worked like a champ!, my plastic screw in fitting and hose off my quart pump adapted easily to my sprayer.

Ayuh,... I build 1 of those a few years ago, with a 1 gallon metal sprayer, 'n an ole metal fittin' off an ole thrown away qt. bottle pump,.....

If I were to have 1 of the Merc drain Systems,.....
I'd pull it ALL Off, 'n use plain ole 1/4 pipe brass pipe plugs,....
With yer "System", ya can't poke, 'n prod the Crud outa the block drains,.....

'n of course,.... I store Dry,..... Air just Don't Freeze,.....
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
In 30+ years of boating and mechanicing, including a stint as a Merc dealership owner, the only engines I ever put antifreeze in were 470s....

Leave the block empty and you have no problems.
 

thumpar

Admiral
Joined
Jun 21, 2007
Messages
6,138
I agree with the above about pulling the drain system and putting in regular plugs. I also agree about antifreeze. If you want to use it drain water, put it in AF and drain again. It is kind of a waste of money though. I am on my 9th year owning a boat and never used it.
 

Starcraft5834

Lieutenant Commander
Joined
Jun 2, 2013
Messages
1,677
I drained mine yesterday..changed fluids.. antifreeze is a waste of money..the only extra protection it offers is the misconception...that folks actually think it protects the engine.. air dont freeze..just drain it
 

HT32BSX115

Supreme Mariner
Joined
Dec 8, 2005
Messages
10,083
First time with this engine, Merc with 3 point drain system

That 3 point drain system works really good on a brand new engine the first time you use it!

But once the boat has been used a season or two, the debris and rust flakes will start collecting and unless you completely remove the 3-point plumbing and expose the drains directly so you can poke wire, thin screwdriver, nail etc in the holes, there no way to ensure that all the water is completely drained out of the block.

THEN, adding anti-freeze to the block may not completely mix with the remaining water that didn't drain out of the block.........

T H E N ..........around next APRIL/MAY you're coming on here asking all of us why you have water in your oil!

Just saying.............


Good luck!


Rick
 

vans

Petty Officer 3rd Class
Joined
Sep 26, 2004
Messages
78
I knew it couldn't be EASY, I know exactly what your speaking of regarding debris in drains, I seen it in other boats I've winterized.
 

_vn_

Petty Officer 2nd Class
Joined
Apr 23, 2012
Messages
131
i am also little skeptic about flawlessness of drain system on my Mercruiser 6.2mpi (garbage from lake).
pulling my engine is a 12 hour job last time it happened, i think extra 30 min of my time and few gallons of RV antifreeze won't kill me - just to have a better sleep ;)
i did it last year on my vp175aq by unscrewing raw water intake hose from engine and plugging it into container with antifreeze - worked like a charm, read that doing it with muffs would be worse due to gravity. planning to do same for old boat and newer 6.2mpi engine
last winter temps in upper VT dipped all the way almost to 0F
 
Top