Winterization ? Need your feedback

[Aadudley]

Before the snow flies and temps drop I thought it wise to get feed back on winterization of our 25SC Volvo Penta 150. As of today I've winterized the water system, air conditioner, generator, waste water system, and lastly the engine. On each of these systems I used the appropriate marine anti freeze undiluted. In each system I closed the sea cock and ran the system until antifreeze exited the hull outlets. I left each sea cock closed but will open them once the boat is put away. I also winterized my bilge, toilet, sinks, changed filters, oil, and filled tanks in addition to additive for long term fuel storage.

Where I'm somewhat concerned is the engine. Since I've always had inboard v8's to winterize, the Ranger system seems much easier due to the anti-freeze coolant system. I made sure the engine was up to temp, shut the engine down, closed the sea cock and connected 6 gallons to the inlet side. Started the engine and ran it until I had anti freeze coolant coming out the hull outlet and then shut down the engine. Entire process took a little over 5 gallons.

Having read as much as I could find I'm smart enough to know what I don't know. Here's my question, have I missed something? On my V8's I would always drain my blocks after all of this. I will open all the seacocks and make sure the bilges are dry once I put up for the winter next week.

Sure would like to have some feedback from those of you diesel owners that have done this time and time again. Sorry for the lengthy message.

Al
True Blue R-25SC

 

[Brian B]

I have the 25SC with the Yanmar engine. I have followed this guide for the past 4 years,
viewtopic.php?f=7&t=762
Did you drain the hot water heater before adding the antifreeze to the fresh water system? Very important or the antifreeze will be diluted. You can also by-pass the heater, drain it and leave the drain valve open. I run 2 gallons of the antifreeze through the engine by pouring it in the sea strainer. I first remove the lower engine zinc so the seawater drains from the engine then reinstall it, the antifreeze will not be diluted. I leave all seacocks closed for storage, why let the antifreeze drain out of the systems?
Make sure the antifreeze in the closed loop of the engine is adequate, you can get an automotive antifreeze tester to test it.

 

[captstu]

Before i permanently winterized by moving to Florida, I did just what you did and then removed the engine zincs with new ones ready to go in at springtime. Helped keep the heat exchanger clean.


Stuart Bell
Ranger 25: Shearwater
(561) 352-1796

 

[YukonRon]

We have the Yanmar 180 in our R25sc, and I have done all of things as mentioned above. I don't think you have missed anything, Al.
First winter I just ran lots of cheap RV antifreeze through the entire fresh water system. Big mistake. It took all summer to get the taste out, and I worried all winter about the hot water tank freezing with the antifreeze being diluted. Now I bypass and drain the hot water tank, blow out the lines, and leave it open. I bought a fitting at the local RV dealer to match the freshwater pump intake, put a short hose on it into a jug of antifreeze, and pump antifreeze through the system that way. No more antifreeze taste in the fresh water tank. My only worry now is if a small amount of water left in the fresh water tank might collect in the outlet fitting and freeze there and break the fitting. Anyone know the shape/configuration of the outlet, and which end of the tank it draws from? I typically crank the trailer up high at the bow to get good bilge drainage. I might rethink that if the water tank outlet is at the aft end of the tank; since the boat is stored under cover anyways.

 

[S. Todd]

Al: I too have a 25SC (2015) with a Volvo. There is no zinc to drain the block on the Volvo. If you purchase the non-toxic antifreeze with engine corrosion inhibitors (the stuff I always purchase is blue/green rather than the pink I used in the fresh water system) I believe it is better to leave it in the block. I always left it in the engine blocks on my Mercruisers for the 32 years before we purchased the Volvo. I have had no negative issues over 35 years leaving the antifreeze in the block. Just did mine on Monday in the hottest temperatures I have ever winterized in.
Todd

 

[YukonRon]

Al: I too have a 25SC (2015) with a Volvo. There is no zinc to drain the block on the Volvo. If you purchase the non-toxic antifreeze with engine corrosion inhibitors (the stuff I always purchase is blue/green rather than the pink I used in the fresh water system) I believe it is better to leave it in the block. I always left it in the engine blocks on my Mercruisers for the 32 years before we purchased the Volvo. I have had no negative issues over 35 years leaving the antifreeze in the block. Just did mine on Monday in the hottest temperatures I have ever winterized in.
Todd

Just to clarify; the zincs on our Yanmar engine are on the seawater cooling side of the block. I do change those, but I do not drain the engine antifreeze from the closed loop coolant system in the block.

 

[knotflying]

My only worry now is if a small amount of water left in the fresh water tank might collect in the outlet fitting and freeze there and break the fitting.

When I had to winterizeI usually put a small amount of RV antifreeze in the tank and drew it up so the fitting has some in it. Then in the spring I put a small amount of water in the tank and flushed it out. I would do this a few times and then after that no odd taste in the water.

 

[rheimb1]

Here's something that I didn't know about RV antifreeze. It has some differences from radiator antifreeze and the most import is that the RV antifreeze will in fact freeze. If you don't believe me put some in a cup and throw it in the freezer. I called the manufacture about this and they said "yes" that is what it does however the trick is, that, it doesn't expand and that's what breaks things.

They had a word of caution with me and that is if you mix the antifreeze with half water (accidently of course) you don't go from -50 to -25. They said you might have freeze protection to 25 maybe 20 and that's above. So they suggest that you do a very good job at flushing, draining and using lots of "pink" juice and you should be good. And they suggested that if you really want to be free of problems, use the 100 below! I have used all "pink i.e. -25" for a couple of years but switched over to the -100 last year on the engine only, it costs 3 times as much ($10/gal) but I have peace of mind. What I do with the engine, is push the pink first and when it comes out I throw in the 100 below for about 4 gallows worth and work a gallon or so through the head as well. Granted, I have never read on Tugnuts that anyone has had a problem with just the pink alone. Over kill? Probably. Am I crazy? Maybe. Do I sleep well? Yep.

 

[YukonRon]

Biggest difference between the RV and radiator (Propylene Glycol) antifreeze is that the rad stuff is toxic. Do Not put it in your fresh water plumbing.
The RV stuff also has 2 types. Cheap stuff is alcohol based, better stuff is Ethylene Glycol based. Alcohol dries out rubber pumps and seals. The EG stuff leaves less yucky taste.
I'd use the -100 if I could too, but can't find it here. Good so far down to -40C but I do worry. I do have to be careful not to dilute it.