Winter Antifreeze methods for 5.0MPI

[JASinIL2006]

Sometimes those methods work, sometimes they don't. When they don't we often see the boat owners here the next spring asking about why their engine oil is milky.

I can drain the engine block, PS cooler and the hose feeding my circulating pump in about half the time it takes to put antifreeze in that kiddie pool. I'm glad I don't have to deal with one of those single-point drain systems or any of its infernal variations.

 

[Scott Danforth]

I addition to AD's comments in post 20 about post 18

a raw water impeller will not draw from a pool like that. it needs to be submerged to be primed. to submerge the raw water impeller in an alpha drive, the anti-cav plate needs to be 4" under the level. in a crank mounted bravo unit, nearly the whole outdrive needs to be submerged.

some dealers have a large tank that they back the whole boat into, others have a set of muffs and a pump in a giant catch pan, then they run the motor for about 20 minutes to ensure adequate mixing and they test the specific gravity of the AF.

if you can drain all the water, the contraption in link 16 works. however it requires either all the water drained from the block.

The dilemma is you cant easily drain the block

 

[RaceCarRich]

There is no way I would follow post 18 for 2 main reasons. A EFI motor is not fogged with oil, this will mess up the sensors. The block was not drained prior to adding AF

That immediately jumped out at me too but not the first time I’ve seen someone recommend fogging an EFI setup.

That guy’s deal was to let the output water flow onto the ground until it turned pink then capture it for recirculation. No real way to know dilution ratio but my thoughts are that if a block and hoses hold X volume and you use 3X volume antifreeze and let it keep mixing and recirculating for a half hour, you should have a 75% antifreeze mix even if nothing drained. Right or wrong?

 

[RaceCarRich]

I addition to AD's comments in post 20 about post 18

a raw water impeller will not draw from a pool like that. it needs to be submerged to be primed. to submerge the raw water impeller in an alpha drive, the anti-cav plate needs to be 4" under the level. in a crank mounted bravo unit, nearly the whole outdrive needs to be submerged.

Guy was using a pump to pressurize feed to muffs so shouldn’t have priming issue.

 

[Lou C]

To paraphrase Dirty Harry "Do yah feel lucky"

if you don't drain the raw water before sucking in the af, its all a matter of how much the thermostat opens, because using this method THAT is the only way raw water can exit the engine. If you think you can tell when the thermostat opens, it can work. On my engine with the OMC/Volvo style stat housing, the way you can tell is....at first the hoses from the stat housing feeding the manifolds will be cool, because the stat is closed, and all the raw water is going out the exhaust. When they start to get warm, that is a sign that the stat opened, and raw water is now exiting the engine via the intake manifold water passage. BUT, there can still be some raw water in there, you really can't guarantee how much exits one way or the other. Not only that, using the -50 or -60 AF this way is especially risky because it is not that strong of a concentration of PG antifreeze, and more likely to be diluted. Using the -100 which is much more expensive would put the odds more in your favor.

This just brings up the main problem I have with I/O boat manufacturers, and I/O engine marinizers...they don't really care about mechanics or maintenance, all they want to do is make it cheap and pretty and push it out the door. If they cared they would:
1) make the engine accessible, you REALLY don't need those stupid steps that take away 1/3 of the engine compartment space, and seating next to the engine can easily be made removable, it just takes a little more time and thought.
2) these are GM automotive engines, they were designed for a pressurized cooling system with antifreeze in it. All inboards, no matter if I/O or straight inboard, should be closed cooled. That would eliminate all this risky foolishness taking short cuts, etc. Outboards are designed for raw water cooling, inboards are not....they are slightly modified car engines...imagine running your Chevy V8 in a car on raw water and having to run out every time it dipped to freezing to drain it, what a stupid system!

Most people who use these methods don't really understand how raw water cooling works, and if you've never had a problem, well then either you've been extremely lucky or it really does not get that cold where you live....

here we have to prepare for occasional dips to zero degrees....

 

[muc]

I have never seen "pink" non toxic anti-freeze that's suitable for winterizing a marine engine.
So............... anytime you see a you tube or anybody who recommends pink......... you know they don't know what they're talking about. And you should take any advise they give with that knowledge.

 

[RaceCarRich]

Got it. What if the stat were removed?

I’m gonna do my best to get to the block drains. At minimum perhaps shoot air up the hoses that lead to them until the dam breaks and water gushes out (assuming they are clogged).

Lou, regarding your point 2, I agree but thinking differently. If these were purpose build marine engines (clean slate design), they’d be designed differently. They’d be more expensive but based on the recent cost of aftermarket engine blocks these days, the cost would be offset by lowered maintenance bills. Perhaps they’d have block drains on the front of the block, perhaps they’d have a dummy head bolt that would take a sample from the water jacket for testing, etc. Wish there was a screw in sensor that could screw into the block drains and remotely display the coolant strength (like a refractometer). If we all boated in distilled water, we could probably have a site glass with density balls. We can only dream.

Regarding all these DIYers getting lucky, I guess ignorance is bliss. That one guy Eddie has a whole series of boat maintenance videos and is usually pretty good. When he pulls his blue drain plugs, the water just rushes out.

 

[RaceCarRich]

SMH... now pink is not good enough? It’s the number one seller around here and what I’ve used in my boat sink system in past years. Okay what’s wrong with pink and what should be used?

 

[Lou C]

Purpose built marine gas engines = outboards!
purpose built marine diesels have closed cooling

a purpose built inboard marine gas engine we aren’t likely to see given economics and how the market is going—->pleasure boats are going outboard.
Pink vs blue etc? Look at the actual freeze temps the -50&-60 (that’s burst temp not freeze temp) start getting hard a few degrees above zero. I used -100 for years (freeze temp approx -55*F) keep in mind the concern is dilution if some water is left in the engine. I now mix up 50/50 Sierra PG antifreeze with water. Freeze temp is -26*F.
they say that the -50 and -60 don't expand but I'm not putting something in my engine that gets hard in the jug at zero degrees (tested this once)....

Standard closed cooling is really the best simplest solution to this problem, not foolish drain systems that clog or taking shortcuts.
If you want to suck in AF and are going to drain first what's the point? It's easier, you use less AF and are not likely to burn an impeller if you simply drain and back fill which is what I've done for nearly 20 years.
Sucking in AF can really only work (without draining) IF...you already have closed cooling, or you have a tub under the drive and a bilge or livewell pump to pressurized the AF flow, this way it gets heated by the engine, is re-circulated and stays hot enough for the stat to stay open. Even though, this would take a LOT of AF to work, I know shops use that or a trough, but they winterized hundreds of boats. For one guy winterizing one boat, manually draining and back filling is really your safest bet.

 

[Lou C]

Engines use -100 with corrosion inhibitors or mix up 50/50 Sierra PG antifreeze with water or 60/40 if you get really cold winters