Coolant Flush on a Yanmar 2GM20F

My newly acquired boat had an engine with rusty looking coolant and pasty globs floating in it. I had to flush 10 times to clean it up. In this video I go through the steps in coolant replacement.

[@nathanreedmitchell9507]

Thanks for the video! Can you recall the temperature range you were looking for?

[@trailsandsails2722]

That's a great question, I should have mentioned that. The Yanmar service manual for the 2GM20F shows the temperature switch normally off at 187F and comes on above 193-202F and the thermostat fully open at 185F. So based on that I was looking at 180 as a max temp since I was looking at the surface of the engine.

[@nathanmitchellmph6606]

@@trailsandsails2722 "The Yanmar service manual for the 2GM20F shows..." Or as I was told in high school: "If all else fails, read the instructions." Thanks for humoring a lazy sailor 😊 And thanks for the succinct video!

[@taiduong8374]

This the most bizarre desmonstration why distilling water but not the real antifreeze just fews dollar a gallon? Just thinking

[@trailsandsails2722]

Thanks for your comment and my apologies for not making this more clear. I was using distilled water to flush out old antifreeze/coolant. It took several flushes with running the engine each time for several minutes to clear most of the old coolant. Perhaps there is a more aggressive flush than distilled water but I could not find anyone to recommend one. After the last flush, I filled the engine with a diesel engine coolant.