For most of her life Silver Maiden had a raw water cooled Palmer P-60. Last winter/spring that was swapped out for a Yanmar 1GM10 which I put together a fresh water cooling system for. I have a heat exchanger from an old diesel generator, the raw water pump goes into one end of the heat exchanger and the other end goes to the exhaust fitting on the Yanmar. The cooling loop through the engine is filled with Dexcool and powered by a small electric pump.
I keep the boat in the water all winter. I sometimes like to go out in the winter. With the palmer I would suck antifreeze into the system when the weather got cold and if I went out after that I would just open the sea cock and go (used bio safe antifreeze).
I am wondering what folks do with the raw water side of their heat exchangers. I am thinking that I could easily drain the water out of the raw water intake line and the pump as well. Looking at things today I do not see an easy way to drain the heat exchanger. There is a valve on it, but mounting considerations forced it to be put someplace that is less than useful for draining and I am not sure if it is functional! The heat exchanger was a cast off at the boat yard.
Should I be looking at making sure I can drain it well, perhaps use my compressor to force water out, or should I suck antifreeze into the raw water side just as I did when I was raw water cooled? My other option is of course a some heater tape around the heat exchanger or an electric circulating heater in the fresh water side to both preheat the engine and keep the heat exchanger warm. I do not really like the idea of being dependent on electricity to keep my heat exchanger from bursting.
I keep the boat in the water all winter. I sometimes like to go out in the winter. With the palmer I would suck antifreeze into the system when the weather got cold and if I went out after that I would just open the sea cock and go (used bio safe antifreeze).
I am wondering what folks do with the raw water side of their heat exchangers. I am thinking that I could easily drain the water out of the raw water intake line and the pump as well. Looking at things today I do not see an easy way to drain the heat exchanger. There is a valve on it, but mounting considerations forced it to be put someplace that is less than useful for draining and I am not sure if it is functional! The heat exchanger was a cast off at the boat yard.
Should I be looking at making sure I can drain it well, perhaps use my compressor to force water out, or should I suck antifreeze into the raw water side just as I did when I was raw water cooled? My other option is of course a some heater tape around the heat exchanger or an electric circulating heater in the fresh water side to both preheat the engine and keep the heat exchanger warm. I do not really like the idea of being dependent on electricity to keep my heat exchanger from bursting.