Winterizing engine. Do Antifreeze turns colorless (after 2 days) inside the manifold?

Scott06

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Muc

What freeze point did the af go in at -50? Question Becomes if it was diluted to -20 ? And if so how do you guarantee the water in the entire block is pushed out by AF not just the one point you sample?

Yes if you never have had a crack that speaks for itself do you guarantee in writing to replace freeze damaged engines? Do you detail exactly how you will winterize do the customer can make an informed descion.

And if you read the thread your customer was the first one to suggest asking for his money back so your thanking the wrong person.

And just because I only winterize a handful of water craft annually doesn't make me or anyone else here less of a competent mechanic than you, this site isn't populated by boobs who just bought their first wratchet set.
 

tpenfield

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A few comments here (now that we are all fired up)

I think the OP's initial question about the 'change in color' of the AF is a good one. . . does it ? :noidea:

The answer that the OP got from the shop seems to imply that the AF went in having a color . . . and now is colorless after 2 days. Really ? That seems to have raised suspicion in the OP's eyes, and others on this forum have shared the same suspicions.

I am sure that the folks that do this sort of stuff for a living have winterization methods that provide a very high level of success, otherwise they would also be in the free engine replacement business.

One thing that many first-timer DIY boat owners may not fully understand, and that has been touch upon in this thread, is that pulling in 4-5 gallons of AF into the engine via the earmuffs does not result in the equal 4-5 gallons of water coming out of the engine (assuming they don't pre-drain the engine). To understand that, then one has to ask the question . . . well then if you don't pre-drain, how much AF and how much water remain in the engine, and what is the resulting freeze/expansion point :noidea:

Air don't freeze . . . at least at any temperatures that we have to worry about (for now) :D
 

bruceb58

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Maybe muc can comment on this:

If the shop has a tank with AF in it and recycles it an puts in right back in, doesn't that tank of anti freeze get slightly diluted with the water that is in each engine they are winterizing? Seems like the freezing point of every boat thereafter gets a solution that is getting more and more dilute. Not even going to talk about the other impurities for the exhaust that gets mixed in.

The marina that winterizes boats where my boat is slipped sure doesn't do it this way.
 

Scott06

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Bruce Mucs point was they check for -20 at the block after so any dilution is accounted for. I personally wouldn't trust this is 100% uniform inside the block after only 5 min running. Sample is just that a sample problem is if it is representative of the whole lot.

Obviously if he has indeed done 3 k engines without a failure this must work.

Personally for mixing and ensuring the drains are free of debris I will continue to take my plugs out.

I don't think professionals should get so offended when customers ask questions as we saw here, but this is why I choose to do my own work. Only one guy to bLame if it it isn't right - me
 

Watermann

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I'm just trying to imagine a busy boat repair shop using a highly trained, seasoned and skilled marine mechanic to suck AF out of a tub for 8 hours a day rather than a min wage floor sweeper or boat washer type. :boink:
 

muc

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Wow, this is like an oil thread. I only replied to it because a few posters who have very high post counts (and a lot of their posts are very good and helpful) started to flame Pete104 for posting the truth. I?ll try to address all the replies one at a time. It might take me a few days.
I?ll start with this link to Mercury Marine
https://www.mercurymarine.com/en/us/faq/?category[]=mercruiser-winterization

QUESTION:
Do I need to put antifreeze into the raw-water/seawater section of the cooling system after draining?
ANSWER:
MerCruiser requires the use of propylene glycol antifreeze (with a rust inhibitor for marine engines) in the seawater section of the cooling system. Damage caused by freezing or improper winterization is not covered by the limited factory warranty.

Yes they do use the word ---- requires -----
This is a change from years ago. Is it possible that times have changed?

One more from that page.

QUESTION:
Can I use propylene glycol (RV antifreeze) in my engine?
ANSWER:
Propylene glycol antifreeze with a rust inhibitor is approved for use in the raw water cooling system for cold weather storage purposes ONLY. However, if your engine is equipped with a closed cooling system, you should always use a 50/50 mixture of ethylene glycol antifreeze and water in this system. Even if you don't live in a freezing climate, you should still use an antifreeze/water mixture rather than plain water. Antifreeze mixtures have superior anti-corrosion and boil over protection properties.

Notice the words -------- rust inhibitor-------
 

muc

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I fully understand what you're saying, Muc, and I can understand why a guy who does this for a living (especially if he's conscientious and successful) might take umbrage at the tone of this thread. The problem is that many of us have had more than one bad experience with folks working on our boats who didn't really seem to know what they're doing. From my perspective, it's not easy to tell the difference between the knowledgeable and conscientious guy who winterized my boat sufficiently and some inexperience/careless mechanic who did it poorly, leading to a cracked engine block. I've read lots of threads here where folks took in a boat to be winterized with antifreeze (or who did it themselves that way) only to have a cracked block come Spring. I don't recall reading many (or any) threads where that happened when the block was drained.

Even more to the point, I guess what I don't understand is how what you described is quicker than just draining the engine. I am not the speediest, but draining my block, circulating pump and P/S hose doesn't take much more than 7-12 minutes, and I've only done it 5 or 6 times. Heck, the slowest part of winterizing for me is warming up the engine to change the oil and then wrestling with my awful Moeller oil extractor to get it to suck the oil out. The draining is a snap.

Not meaning to be argumentative, but it really doesn't seem that the antifreeze method saves any time. I don't get any anticorrosion benefits, of course, but I boat only in freshwater and I don't really feel that's a big issue.


It wasn't so much the tone as it was someone getting flamed for being right.

I do understand that there are some REALLY bad boat shops out there and have often thought about writing a post on how to pick a good one. Couple of thoughts on that, don't pick based on $ or the fact they can get you in today.

Couple of reasons it's quicker.
1. some engines are much tougher than yours ---- think twin Bravo's and there is less than 2" between the exhaust manifolds and less than 6" in front of the motors. Don't know anybody who could drain those in less than 1/2 hr. Also remember that most people do the easy 3.0L engine's at home and bring the hard ones to us.
2. The antifreeze is heated so the engine and oil come up to temp a lot faster.

Ran out of time for right now, but I will try to address anti-corrosion benefits later.
 

Scott Danforth

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Last time I checked with the engineers in Charleston, Mossville, Waterloo, Fond du Lac, Chesapeake, Plymouth, Millington, and Little Mountain draining was still required. The last factory manuals I looked at still state drain first, then add antifreeze if you want. (new Merc manuals have 10 pages on draining alone). Recently Mercruiser added the notes PG with Rust inhibitor to the website, however have not updated all the prior service manuals.

and as a power train engineer with a background in cooling systems for Marine, Industrial, and mobile off-highway with a stint manufacturing marine HX's, my personal and professional opinion is drain first.

with a block and manifolds full of water (about 5 gallons) you need a huge tank of a minimum of 8-10 gallons of 100% PG to cycle thru, mix, dilute, etc. to end up with -20F (about a 50/50 mix of PG/Water). and last time I checked, Wisconsin alone had over 30 days of -30 degree weather not to long ago.

propylene-glycol-capacity-correction-factor-table.jpg


Now if that same tub is used on the next boat, without draining, it will further be diluted. I still question any mechanic that doesnt drain first. Even on a large twin or triple set up, while access it tight, it is still best to drain.

Now back to the OP question on PG changing color.... it cant. it can get diluted and the picture in post 1 shows significantly diluted PG. it should be tested for specific gravity with any of the commercially available testers for PG (Thexon, Victor, Prestone, etc.)
 

Rick Stephens

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Puts posters between a rock and a hard place when you compare what a top flight marine shop will do with the equipment to handle dozens, if not hundreds of winterizations a year, with the typical boater who comes here to find out safe practices. I appreciate greatly the world view and assistance given on these forums by those who make a living working on boat engines. They are a godsend and it is incredibly charitable of them to give us their time. I also appreciate all the aggregated knowledge of those who learned safe practices, maybe the hard way, in their own driveway. Thank you all.

The only way I would jump up and state the OP needs his money back is if he can prove the AF protection of the colorless fluid in his engine is not appropriate to the task. Fairly easily determined, at that.

Rick
 

brian4321

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After all the dust settles, all the more experienced people will keep doing it the way they've always been doing it, and the novice's will be more confused than ever...my advice is, either do it yourself by following the mercruiser manual , or have someone do it that does it as the manual recommends...just my 2?
 

ericga

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Replacing the "Your theory on the block must be drained is total BS" by "We use a different method that with the proper tools and equipment allow us to do it faster on difficult configurations" would have make this thread evolve in a much more constructive way.
 

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achris

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Back to the op question. If you have doubts, take a sample from the exhaust manifold. Regardless of whether the engine was drained or not, the exhaust manifolds will carry whatever was sucked up by the flushers. If they say they used pink AF and is pink in the exhaust manifold but clear in the engine, there's a problem.
 

Lou C

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I would take a sample from the block drain in a paper cup and put it in the freezer. If it stays liquid you're fine. If not either drain it or take it back. I always drain and back fill with -100 AF. This is the best way for a guy who only does 1 or 2 engines a year.
The shops that use AF and do not drain have a way to keep the AF hot by re circulating it. Not so easy to do in your driveway. Personally I feel that all of this drama is pure cost cutting on the part of marinizers. These engines were designed to be closed cooled with a pressurized cooling system and that is how they should be installed from new. Look at cooling systems in outboards that were designed to be raw water cooled from the start. Cast iron always builds up a layer of corrosion even in fresh water that impedes heat transfer.
 
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airdvr1227

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A little topic wandering here. I worked in sales at a fairly large marina here in Ohio. They had a method of winterizing I don't hear discussed.

They had a home made setup that was basically a 4 x 4 metal pan with a bilge pump mounted in the bottom connected to a pair of muffs. They purchased what looked to be about a 200 gallon container of something they called "blue pop". They would fill the pan with this blue pop. Back in a boat to be winterized. Hook up the muffs and turn on the bilge pump. Start the engine and let it run. The pan would catch whatever ran out of the motor. They had a clear device they looked through to determine the specific gravity of the mix running through the engine. When they were happy (about 5 minutes) they fogged the motor, disconnected everything and brought in the next boat. That production line winterization went on for weeks. We have some pretty cold winters here on the North Coast and I never heard anyone complain about a cracked anything in the spring.
 
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wrvond

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My freezer is set at only 0?F. Many places get colder than that.

I think he's proposing a simple "go - no go" test. If the colorless liquid freezes in the household freezer, it's water, if it doesn't freeze in the household freezer, then the OP knows it's not water.
 

bruceb58

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I think he's proposing a simple "go - no go" test. If the colorless liquid freezes in the household freezer, it's water, if it doesn't freeze in the household freezer, then the OP knows it's not water.
The problem is of course when it doesn't freeze at 0? and it does freeze at -5?. I would probably do a different type of test.
 
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