Join Date: Jul 2007
Location: Truckee, CA
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Re: Yanmar 4JH-2E using coolant
Possibly a small leak from the coolant piping inside the heater into the fresh water supply? Generally, after the engine warms up there is pressure in the coolant system, assuming you have the filler cap secured. If you taste the hot water and is sweet, it has coolant in it. As the anti freeze is toxic, don't taste too much of it, maybe a drop on the end of your finger? or, as mentioned earlier, use a fluorescent dye in the coolant, safer that way.