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akps190
11-22-2010, 11:33 PM
I live in Alaska and have a 98 PS190 with LT-1 engine; and no, I dont know Sarah Palin.....

During winterization, I typically run the boat across the lake to the marina where it is stored during the winter, and while the engine is still warm, run antifreeze thru it (thermostat open), and then drain it. I use the Sierra (propylene glycol) because a) dont want to trash the lake next summer, and b) heard that ethylene glycol was bad for the aluminum heads on the LT-1.

My question..... is there a problem draining the engine while it is still warm?? I am concerned about the lack of fluid in the block could cause the block to crack if it drained while warm (or it is actually pretty hot). IE, no heat sink.

On the other hand, doesnt seem like the engine can get any hotter than it is at the time it is drained. No additional source of heat into the engine after it is shutdown. I havent seen a spike on the temp gauge.....

Also, I have used a shop vac with hose on the blower side to blow air thru the engine and out thru the drain plugs to get all the water out. Seems to work pretty good.

Thoughts???

east tx skier
11-23-2010, 12:11 AM
I have never heard of this being an issue and routinely drain warm. The differential is admittedly a bit smaller in my neck of the woods.

Hollywood
11-23-2010, 10:39 AM
I have drained my engine hot many times, haven't had any problems yet. Pouring cold A/F in an empty hot engine could be a problem but the air will not do any damage.

bigmac
11-23-2010, 06:58 PM
Antifreeze of any kind won't harm your aluminum heads as a winterization storage concept so I wouldn't worry about that. Ethylene glycol can harm aluminum heads in prolonged use as a coolant at high, engine-head, temps (phosphate "hot-spot" erosion) but that's a rare condition and not applicable to your engine since you're not using the AF as a coolant. What kind of radiator do you have in your car? Aluminum? Are you using ethylene glycol as a coolant? Has it harmed your radiator?


And you're right that propylene glycol won't harm the environment so you can start it up next spring in your lake without fear. That's a better way to go unless you're prepared to recover all the ethylene glycol in your driveway and dispose of it. Propylene glycol is the primary ingredient in a variety of consumer products from foods to cosmetics to "personal lubricants".

akps190
11-23-2010, 07:31 PM
Thanks for the feedback......

kevkan
11-24-2010, 07:35 PM
A quote from a lengthy diatribe I posted on a similar topic. Curious, does anyone have a scientific reason for the preference of RV over automotive antifreeze?

"
A few facts:
Automotive antifreeze is generally Ethylene Glycol (EG) while RV antifreeze is Propylene Glycol (PG). Concentrated EG is toxic to humans and animals, while similar concentrations of PG are considered safe. However, this does not translate into the overall environmental impact of using either of the two products. Once dilluted, EG is no longer toxic, so the hazard/risk is in leaving a container open, or an undiluted puddle on the ground. Same could be said of gasoline, which I am sure we all use.

Both EG and PG are relatively rapidly biodegradeable. "Ethylene and propylene glycol are the two primary chemicals in antifreeze and both are highly biodegradable in both soil and water and therefore, do not tend to accumulate in the environment or bio-concentrate in animal tissues from contaminated water. The primary health concern for antifreeze, especially one containing ethylene glycol which is more toxic than propylene glycol, is ingestion because it will produce toxic metabolites in the body. Cats, dogs, birds and other animals have died from drinking spilled ethylene glycol antifreeze or coolant containing this antifreeze. Natural rainfall will usually prevent antifreeze components from accumulating on driveways or parking areas. These chemicals can also be easily rinsed from parking areas with a hose. On the other hand, leaks of petroleum products from power steering units, transaxles or engines are of greater environmental concern than antifreeze chemicals because these oil products do not readily degrade and they often contain metals from mechanical wear and corrosion." (http://www.freedrinkingwater.com/wat...-pollution.htm)

I realize that common sense tells us, "a chemical deadly to humans and pets must be murder on a lake", however this is not what science proves at all. In fact, lesser concentrations of PG ("safe" RV antifreeze") are as harmful to marine life as greater concentrations of EG ("deadly" antifreeze). More importantly, realistic concentrations of either EG or PG are not going to be an environmental hazard for any lake, unless a northern climate airport tarmac dumps into it. (Yes, these chemicals are what is sprayed on planes all winter long.)

If you want a very scientific, 400 page, read on the subject, go to http://www.epa.gov/waterscience/guid...rt/airport.pdf.
In a nutshell "Table 9-1 summarizes aquatic toxicity data from studies that directly compare
ethylene glycol and propylene glycol under the same or similar experimental conditions. In
general, the data show that ethylene glycol and propylene glycol exhibit aquatic toxicological
effects at concentrations within the same order of magnitude. Although EPA does not use such a system, the U.S. Fish and Wildlife Service Classification System for Acute Exposures defines “relatively harmless” as any chemical with an LC above 1,000 mg/L (3). The test results shown in Table 9-1 indicate that ethylene glycol and propylene glycol may be classified as “relatively harmless,” as defined by the U.S. Fish and Wildlife Service."

So why do I like more expensive EG in my engine? Better corrosion prevention. Cheaper PG in ballast? Nothing to corrode, and need more of it. I'll try to get as much out on land, but some of that in the ballast will make its way to the lake, I'm sure. That said, over the years, I have generally used 1/2 gallon of EG to winterize my boat. It got dumped and dilluted on my rural drive, with no storm sewer, each spring. I doubt I have done as much environmental damage as someone dumping 3-5 gallons of PG directly into a lake.

If anyone has a scientific rational for abandoning the use of EG, I will certainly consider it.
"

bigmac
11-24-2010, 11:09 PM
Spill it on the ground, dog licks it up. Not good. No point to EG, not at all superior to marine -100 PG, which does contain phosphates and provided good corrosion prevention.

I acknowledge that it is non-persistent and degrades rapidly. That does not make it less toxic.


.

vision
11-25-2010, 01:22 AM
EG is quite toxic. Fatal for almost all animals, including humans, upon ingestion of relatively small amounts. It is unfortunately sweet, encouraging ingestion.

Why it is still sold when less toxic alternatives are available, is beyond me. I assume solely because of cost.

TallRedRider
11-26-2010, 11:43 AM
EG is quite toxic. Fatal for almost all animals, including humans, upon ingestion of relatively small amounts. It is unfortunately sweet, encouraging ingestion.

Why it is still sold when less toxic alternatives are available, is beyond me. I assume solely because of cost.

I was told that EG has a bit lower freezing point than PG and might be preferred for our friends who are in deep subzero areas. A brief search for me turned up that 100% PG won't freeze until at least 60 below zero farenheit. So I am not sure that is a real issue.

The toxicity to animals who lick up EG is a real issue if you have animals that might find some of it dripping from your intake.

JimN
11-26-2010, 12:26 PM
I live in Alaska and have a 98 PS190 with LT-1 engine; and no, I dont know Sarah Palin.....

During winterization, I typically run the boat across the lake to the marina where it is stored during the winter, and while the engine is still warm, run antifreeze thru it (thermostat open), and then drain it. I use the Sierra (propylene glycol) because a) dont want to trash the lake next summer, and b) heard that ethylene glycol was bad for the aluminum heads on the LT-1.

My question..... is there a problem draining the engine while it is still warm?? I am concerned about the lack of fluid in the block could cause the block to crack if it drained while warm (or it is actually pretty hot). IE, no heat sink.

On the other hand, doesnt seem like the engine can get any hotter than it is at the time it is drained. No additional source of heat into the engine after it is shutdown. I havent seen a spike on the temp gauge.....

Also, I have used a shop vac with hose on the blower side to blow air thru the engine and out thru the drain plugs to get all the water out. Seems to work pretty good.

Thoughts???

Hot is one thing and overheated is another. If it's at normal operating temperature, it shouldn't be an issue unless the air temperature is extremely low and the outside cools very rapidly. If the motor box is closed after draining and it's allowed to cool, I doubt you'll have any problems.


OK, you don't know Palin but can you see Russia?:D

Abe
11-26-2010, 07:26 PM
I live in Scotland UK, So very cold winters here. I have never put antifreeze in my mc, - I did with my old stern drive. My question is, If you run A/F into the motor then drain it out again, what really is the point of running it thu in the first place. I know its a big question every year at this time, To A/F or not.

I was under The impression if the motor is drained correctly, then there is no water in there to freeze so no damage can be done. - This is what my dealer told me when I purchased my mc. So, what part of the motor retains the A/F after its drained. I,m interested to know what it actually protects IF its drained.

Cloaked
11-26-2010, 07:35 PM
I live in Scotland UK, So very cold winters here. I have never put antifreeze in my mc, - I did with my old stern drive. My question is, If you run A/F into the motor then drain it out again, what really is the point of running it thu in the first place. I know its a big question every year at this time, To A/F or not.

I was under The impression if the motor is drained correctly, then there is no water in there to freeze so no damage can be done. - This is what my dealer told me when I purchased my mc. So, what part of the motor retains the A/F after its drained. I,m interested to know what it actually protects IF its drained.Any miscellaneous low points of one spot or another that may hold a small amount of water. For me, I just drain it without any additional formula.

One place for example on the PCM 351 is a low point just under the drain plugs on the exhaust risers. Every drop may not come out, thus it would be mixed (or not) with AF.

Just think, we'll get to go through this again next winter too... all of the debate and preferences... :D

akps190
11-29-2010, 08:25 PM
I use AF because...... a) I am paranoid, b) concerned about any water that may not drain out, and c) have read about warming up the engine to open the thermostat, so am concerned about the potential of trapped water due to closed thermostat (which may not be valid and takes us back to "a"). The previous owner said he just pulled the drain plugs and hoses and never had a problem.

Comp boats are hard to come by up here, and a lot of them seem to have cracked blocks, which I dont understand cause eveybody that lives here knows its going to freeze.....

Aso, I use the Sierra PG AF because it has corrosion inhibitors, I can mix myself, and I dont trust the RV AF. I use the RV AF in my toilet bowl at my cabin and it slushes up pretty thick at -20F.

TallRedRider
11-30-2010, 03:24 PM
I was under The impression if the motor is drained correctly, then there is no water in there to freeze so no damage can be done. - This is what my dealer told me when I purchased my mc.

X 2.

I think that there are always trickles of water in the engine even when drainged properly. I was told by my dealer in Salt Lake City that properly draining it and blowing out the heater is all that is needed. The small amounts of water left in there will freeze, but have plenty of space to expand and will not be able to do any damage.

Even if RV antifreeze becomes thick at -20 degrees, it does not expand like water when it freezes...so it could freeze solid for all any of us could care.

bigmac
11-30-2010, 08:02 PM
I use antifreeze because it's the way my dealer winterizes my boat, but there's nothing wrong with doing it the way MasterCraft recommends - just drain it completely and leave the lower hoses detached and disconnected, plugs out, etc...you just have to go through all that "de-winterizing" in the spring. For me, with the block/pump and the heater full of -100 PG, I drive it from his shop to my storage garage, plug in the battery tender and two air warmer/circulators (prevent's mold) and forget about it until the spring. Then I just put it in the lake and start it up.

Keeping it "pickled" in AF that way keeps the RW impeller from drying out. Next spring will be my 5th year on this impeller.

Edit: I don't trust just blowing out the heater core. Some water will inevitably remain and will drip drip drip down to the dependent portion of the core where it will freeze and burst the core. I would always pump antifreeze through the heater core before storing for the winter. Only takes about 5 minutes.

Hollywood
12-01-2010, 01:10 PM
The small amounts of water left in there will freeze

or evaporate if you leave all the plugs out for some airflow.

I would fill the heater core with A/F to inhibit corrosion.