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Don’t flush anti-freeze into the canal

Raw water systems, as far as I am aware and is the case with my own boat, draw water from the canal, pump it through the engine to cool it, then the water is exhausted back to the canal. To introduce anti-freeze into the system would be grossly irresponsible and threatening to the wildlife.

To do what the article suggests safely with a raw water system, the hose exhausting the water overboard and the intake hose would need to be disconnected and placed into a container of anti-freeze mixture before running the engine. These hoses would have to remain disconnected and before using the boat again the procedure would need to be repeated with fresh water to flush any anti-freeze from the system.

Should the above be what was intended it certainly didn't explain it very well and could land boat owners in trouble.

Monty Vann
By email

Steve Vaughn, RYA inland trainer, responds:

It is rightly pointed out that no responsible boater would ever allow any
hazardous chemical to be discharged into the canal or river. The article should have highlighted that the anti-freeze mix should not be allowed to drain into the water either at the time of filling or when flushing out the system at the beginning of the next season. Many lighter craft will be taken out of the water during the winter which makes the process much easier than it does for canal craft staying afloat but it can still be done with care. It is difficult with a short article to go into the depth that we would sometimes prefer so this process wasn’t given as much attention as it should. However, all RYA training centres conducting the Diesel Engine Maintenance Course will address winterisation in much greater detail.