<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40"><head><meta http-equiv=Content-Type content="text/html; charset=utf-8"><meta name=Generator content="Microsoft Word 15 (filtered medium)"><!--[if gte mso 9]><xml>
<w:WordDocument>
<w:DontUseAdvancedTypographyReadingMail/>
<w:DontUseJustificationAdvancedTypographyReadingMail/>
<w:DontUseHyphenationAdvancedTypographyReadingMail/>
</w:WordDocument>
</xml><![endif]--><style><!--
/* Font Definitions */
@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
@font-face
{font-family:Aptos;}
@font-face
{font-family:"Century Gothic";
panose-1:2 11 5 2 2 2 2 2 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
font-size:12.0pt;
font-family:"Aptos",sans-serif;}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
span.EmailStyle21
{mso-style-type:personal-reply;
font-family:"Century Gothic",sans-serif;
color:windowtext;}
.MsoChpDefault
{mso-style-type:export-only;
font-size:10.0pt;
mso-ligatures:none;}
@page WordSection1
{size:8.5in 11.0in;
margin:1.0in 1.0in 1.0in 1.0in;}
div.WordSection1
{page:WordSection1;}
--></style></head><body lang=EN-CA link=blue vlink=purple style='word-wrap:break-word'><div class=WordSection1><p class=MsoNormal><font size=1 face="Century Gothic"><span style='font-size:9.0pt;font-family:"Century Gothic",sans-serif;mso-fareast-language:EN-US'>JSARCH is correct for many types of modern sprinkler heads, but there are still several types that use one form or another of fusible links. I apologize for being a pedant on this topic (sorry, it is what I do – both being a pedant and design of automatic fire protection systems).<o:p></o:p></span></font></p><p class=MsoNormal><font size=1 face="Century Gothic"><span style='font-size:9.0pt;font-family:"Century Gothic",sans-serif;mso-fareast-language:EN-US'><o:p> </o:p></span></font></p><p class=MsoNormal><font size=1 face="Century Gothic"><span style='font-size:9.0pt;font-family:"Century Gothic",sans-serif;mso-fareast-language:EN-US'>Mandatory Healey content : what is the advantage of draining the water from one’s cooling system if the engine is overheating?<o:p></o:p></span></font></p><p class=MsoNormal><font size=1 face="Century Gothic"><span style='font-size:9.0pt;font-family:"Century Gothic",sans-serif;mso-fareast-language:EN-US'><o:p> </o:p></span></font></p><p class=MsoNormal><font size=1 face="Century Gothic"><span style='font-size:9.0pt;font-family:"Century Gothic",sans-serif;mso-fareast-language:EN-US'>Thanks.<o:p></o:p></span></font></p><p class=MsoNormal><font size=1 face="Century Gothic"><span style='font-size:9.0pt;font-family:"Century Gothic",sans-serif;mso-fareast-language:EN-US'><o:p> </o:p></span></font></p><div><p class=MsoNormal><b><font size=2 color=navy face="Century Gothic"><span lang=EN-US style='font-size:10.0pt;font-family:"Century Gothic",sans-serif;color:navy;mso-ligatures:standardcontextual;font-weight:bold'>Bob England<br><br></span></font></b><font face="Century Gothic"><span style='font-family:"Century Gothic",sans-serif;mso-ligatures:standardcontextual'><o:p></o:p></span></font></p></div><p class=MsoNormal><font size=1 face="Century Gothic"><span style='font-size:9.0pt;font-family:"Century Gothic",sans-serif;mso-fareast-language:EN-US'><o:p> </o:p></span></font></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in;font-size:pt'><p class=MsoNormal><b><font size=3 face=Calibri><span lang=EN-GB style='font-size:12.0pt;font-family:"Calibri",sans-serif;font-weight:bold'>From:</span></font></b><font face=Calibri><span lang=EN-GB style='font-family:"Calibri",sans-serif'> Healeys <healeys-bounces@autox.team.net> <b><span style='font-weight:bold'>On Behalf Of </span></b>JSARCH via Healeys<br><b><span style='font-weight:bold'>Sent:</span></b> November 3, 2025 12:44 PM<br><b><span style='font-weight:bold'>To:</span></b> 'Bob Spidell' <bspidell@comcast.net>; healeys@autox.team.net<br><b><span style='font-weight:bold'>Subject:</span></b> Re: [Healeys] Core plug query<o:p></o:p></span></font></p></div></div><p class=MsoNormal><font size=3 face=Aptos><span style='font-size:12.0pt'><o:p> </o:p></span></font></p><p class=MsoNormal><font size=2 face=Calibri><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'>More often than not, automatic fire sprinklers are activated by a glass bulb filed with a liquid that expands and breaks the bulb which then opens the fire sprinkler head. Bismuth is used in fusible links which that melt at certain temperatures to activate automatic fire doors.<o:p></o:p></span></font></p><p class=MsoNormal><font size=2 face=Calibri><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p> </o:p></span></font></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><font size=2 face=Calibri><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;font-weight:bold'>From:</span></font></b><font size=2 face=Calibri><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'> Healeys <<a href="mailto:healeys-bounces@autox.team.net">healeys-bounces@autox.team.net</a>> <b><span style='font-weight:bold'>On Behalf Of </span></b>Bob Spidell via Healeys<br><b><span style='font-weight:bold'>Sent:</span></b> Friday, October 31, 2025 11:13 AM<br><b><span style='font-weight:bold'>To:</span></b> <a href="mailto:healeys@autox.team.net">healeys@autox.team.net</a><br><b><span style='font-weight:bold'>Subject:</span></b> Re: [Healeys] Core plug query<o:p></o:p></span></font></p></div></div><p class=MsoNormal><font size=3 face=Aptos><span lang=EN-US style='font-size:12.0pt'><o:p> </o:p></span></font></p><p class=MsoNormal style='margin-bottom:12.0pt'><font size=3 face=Aptos><span lang=EN-US style='font-size:12.0pt'>I did a little diggin ... <br><br>Apparently, they are designed to melt if the engine overheats, which would be grounds for voiding the warranty on a re-man. I wonder if the plug is made of bismuth, which is what sets off automatic fire sprinklers.<br><br><a href="https://www.toyotanation.com/threads/mysterious-plugs-in-engine-block.1659464/">https://www.toyotanation.com/threads/mysterious-plugs-in-engine-block.1659464/</a><o:p></o:p></span></font></p><div><p class=MsoNormal><font size=3 face=Aptos><span lang=EN-US style='font-size:12.0pt'>On 10/31/2025 5:08 AM, Simon Lachlan via Healeys wrote:<o:p></o:p></span></font></p></div><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><p><font size=3 face=Aptos><span lang=EN-GB style='font-size:12.0pt'> I saw this on Facebook just now. Just curious….what’s that thing in the middle of the core plug? And, if it’s a good thing, why don’t all the plugs have one? </span></font><span lang=EN-US><o:p></o:p></span></p><p><font size=3 face=Aptos><span lang=EN-GB style='font-size:12.0pt'>Thanks, Simon</span></font><span lang=EN-US><o:p></o:p></span></p><p class=MsoNormal><font size=3 face=Aptos><span lang=EN-US style='font-size:12.0pt'><o:p> </o:p></span></font></p></blockquote></div></body></html>