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</o:shapelayout></xml><![endif]--></head><body lang=EN-AU link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Times New Roman","serif"'>G’day<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Times New Roman","serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Times New Roman","serif"'>I know the subject of fitting a coolant expansion bottle has been covered before, but this has a twist as it concerns a Healey and not an Austin-Healey.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Times New Roman","serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Times New Roman","serif"'>Our Healey Duncan has its original cooling system that is unpressurised. It’s assisted by an electric fan in front of the radiator, but with our warmer climate it persists is dumping its coolant out through the overflow pipe.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Times New Roman","serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Times New Roman","serif"'>The radiator cap is a screw on type and the overflow pipe exits the radiator header tank separately in front of the cap. Being unpressurised there is nothing to stop the hot and expanded coolant from exiting via the overflow pipe.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Times New Roman","serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Times New Roman","serif"'>I am thinking of fitting a coolant expansion bottle but am wondering if this will work on an unpressurised system. It seems to me that it should not make any difference, because if the coolant cannot escape to the outside world when it expands then it should flow back into the radiator once it cools.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Times New Roman","serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Times New Roman","serif"'>Any opinions?<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Times New Roman","serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Times New Roman","serif"'>Thanks<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Times New Roman","serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Times New Roman","serif"'>Patrick Quinn<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Times New Roman","serif"'>Blue Mountains, Australia<o:p></o:p></span></p></div></body></html>