Originally Posted by JohnRPollard
Another question that comes to mind if the boat is on the hard when you do the winterization:
On the raw water cooled engines, wouldn't the engine need to be run long enough for it to warm up and for the thermostat to open? If the engine is cold when you run the anti-freeze through the system, won't the antifreeze largely bypass the engine block because of the closed thermostat?
I suppose you could bypass the thermostat by temporarily removing it.
In a system equipped with a heat exchanger, you only have to worry about filling the intake lines, exchanger, and exhaust with anti-freeze, since the engine block already contains it.
For this reason, I normally winterize the engine before end of season haul-out. The first season with this boat however, it was hauled out and brought inside for barriercoating the bottom - prior to winterizing the engine.
After bottom work was completed she was moved back out to sub freezing conditions. So, using a 5 gal pail with a hose leading from it to the raw water strainer, a long garden hose was then led from the same pail to a boatyard water tap. After filling the bucket with the garden hose I started the engine with the hose's nozzle adjusted to the water pump's draw rate, and ran it for several minutes to reach operating temperature.
I then shut off the hose nozzle when a couple gallons of water was left in the pail while pouring two gallons of undiluted antifreeze into the bucket - killing the engine when the antifreeze was seen ejecting from the wet exhaust. My engine is fresh water cooled, but this process assured me of the proper 50/50 mix and a total fill, of the raw water sections of the engine.