R 21 Impeller Removal?

[BlueDragonfly]

I was just considering the impending (first time) winterization process and taking stock of some of the parts I've accumulated. I remember reading (in tugnuts) someone recommended that for really cold weather, the water impeller should be removed as it would inevitably become brittle and be damaged from the cold. If anyone has done this; wouldn't all the pink antifreeze that you just added seep out in the process? The logic for removal is sound and I want to do this. Can't remove impeller prior to cranking PINK thru, and the relative position of the impeller suggests that I'll loose most of my fluid if I try and remove. Did you solve this?
By the way, I managed to pass 100 hrs on the Yanmar in my first summer! Is anyone else getting these numbers or should I be checking the counter?
Roger

 

[rt11002003]

Two thoughts: Leave the impeller there during the winter, change it during spring commissioning. Second, remove the impeller, pump the antifreeze thru the system with a low pressure pump; put the new impeller in during spring commissioning.

gene

 

[ozoner]

They get brittle with cold, but unless you actually try to turn the engine over while it is bitterly cold (thus rotating the brittle impeller blades), the cold shouldn't do any damage to the impeller if left in place. When it warms up in the spring it should be as flexible as usual.

 

[abcandjrc]

If 100 hours does not seem possible, it is possible you left the key in the "on" position once. Most hour meters are 12VDC driven. But the alarm should have been buzzing if you did. I bet you just forgot that "Time flies when you are having fun!"

Sign that I love seen in a bakery in Marsh Harbour: "Time flies like the wind. Fruit flies like bananas." (As neat a double entendre as you will ever see in your life.)

 

[tuggertoy]

Or, pump the propylene glycol through the system as usual with the raw water pump. Make sure you see enough of the pink stuff being discharged through the exhaust through hull. I find that a gallon is enough if I have first already drained the water out of the raw water system by removing the sea strainer with the seacock open and then draining the Vetus water lift muffler on my 3YM20. There is actually a drain fitting for this purpose at the bottom of the muffler assembly. Then I replace the sea strainer and pump the glycol through the system. After I am satisfied that the system is properly winterized I remove the raw water pump cover and the impeller. Yes, some of the glycol leaks out but this doesn't matter as its purpose is to keep any water in the system from freezing. If there is nothing in the system you would not have to do this at all. My point being that now the lower hose from the pump to the heat exchanger and maybe part of the raw water side of the heat exchanger tank are now empty of any fluid - but there should be no water either so nothing will freeze. I then replace the raw water pump cover loosely so I don't loose the screws and store the impeller in a ziploc bag for the winter. I have seen impellers that are left in the pump for the winter get stuck inside the pump housing which causes them to tear when you fire the motor for the first time in the following boating season.

Eric

 

[BlueDragonfly]

Thanks to you all for your enlightened responses, Very much appreciated! 😀