Heater Core

<body topmargin=0 leftmargin=0 marginheight=0 marginwidth=0> <table cellpadding=0 cellspacing=0 border=0><tr> <td valign="top" colspan=2 height=90 BGCOLOR="#006633" TEXT="#F7F7FF" bgproperties="fixed" background="079005a0ddvuru.png"> <div> <A HREF="http://www.vernco.com/index.htm" TARGET="_top" TITLE="http://www.vernco.com/index.htm"><U><B>home</B></U></A><B>     |     </B><FONT SIZE="5" COLOR="#FFCC66" FACE="Arial" ><B>Vern</B><B>co.com</B></FONT></div> <div> back to<B>  </B><A HREF="index.htm" TARGET="_top" TITLE="Harrison Heater"><U><B>Harrison Heater</B></U></A></div> <bR> <div> <A HREF="http://www.vernco.com/id173.htm" TARGET="_top" TITLE="http://www.vernco.com/id173.htm"><U><B>Site Map</B></U></A></div> <div> </div> </td> </tr><tr> <td valign="top" width=150 BGCOLOR="#669966" TEXT="#080000"> <div> <B>Heater Core</B></div> <div> <A HREF="id583.htm" TARGET="_top" TITLE="Paint and Decal"><U>Paint and Decal</U></A></div> <div> <A HREF="id582.htm" TARGET="_top" TITLE="Fan Motor"><U>Fan Motor</U></A></div> <div> <A HREF="id584.htm" TARGET="_top" TITLE="Installation"><U>Installation</U></A></div> <bR> </td> <td valign="top" height=390 BGCOLOR="#FFFFFF" TEXT="#080000"> <div> The heater case is made of two stamped sheet metal halves joined by small screws around the perimeter.  This first view is from the back, showing the angled coolant lines that pass through the firewall.  Note the two louvers below the heater core that direct some of the warm air towards the driver's side.  A protruding mounting stud on the back is broken, which seems to be a common problem with these heaters:</div> <bR> <div> <A HREF="id588.htm" TARGET="_top" TITLE="Backside View Bottom"><U><IMG SRC="994af460.jpg" border=0 width="175" height="70" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></U></A></div> <bR> <div> Here is a top view of the back side.  The fan draws air inward and pushes it out the bottom:</div> <bR> <div> <A HREF="id589.htm" TARGET="_top" TITLE="Backside View Top"><U><IMG SRC="996af410.jpg" border=0 width="175" height="65" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></U></A></div> <bR> <div> With the case halves separated, the core is readily visible.  Two small screws at each end secure the core to the outer case half:</div> <bR> <div> <A HREF="id587.htm" TARGET="_top" TITLE="Heater Exploded Core in Case"><U><IMG SRC="998af4f0.jpg" border=0 width="175" height="79" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></U></A></div> <bR> <div> One of the core's mounting brackets was loose and was soldered back in place:</div> <bR> <div> <A HREF="id591.htm" TARGET="_top" TITLE="Soldering Core Bracket"><U><IMG SRC="99a96580.jpg" border=0 width="150" height="88" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></U></A></div> <bR> <div> The outside of the core needed a good cleaning, as there was much debris blocking the airflow.  Anything that gets inside the heater case will end up sitting on the core.  Low pressure compressed air made quick work of the cleaning.  Numerous fins were found bent, also blocking airflow.  A small pair of pliers and a fine awl were used to straighten the fins:</div> <bR> <div> <A HREF="id590.htm" TARGET="_top" TITLE="Straightening Fins"><U><IMG SRC="99c7d750.jpg" border=0 width="125" height="117" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></U></A></div> <bR> <div> If new paint is needed, don't just glob on whatever paint is handy.  Most paints are too thick and will slow the heat transfer.  Use radiator paint, available at good auto parts stores.  For an online source, order part #10040Z at <A HREF="http://www.eastwoodco.com/" TARGET="_blank" TITLE="http://www.eastwoodco.com/"><U>Eastwoodco.com</U></A>.</div> <bR> <div> A leak check was performed with very low pressure compressed air.  Don't hook this up to shop air or you will severely damage the core from too much pressure.  I capped both lines and drilled a small hole in one for a basketball pump.  I filled up the bathtub with water and looked for bubbles from any leaks:</div> <bR> <div> <A HREF="id592.htm" TARGET="_top" TITLE="Core in Tub"><U><IMG SRC="99eaf4c0.jpg" border=0 width="175" height="76" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></U></A></div> <bR> <div> Should you find leaks, any radiator shop can repair the core.  They could also chemically clean the inside to remove any built-up scale.  If your heater's core is too far gone, a good radiator shop could custom build one to match.</div> <bR> </td> </tr></table></body>