View single post by edward_davis
 Posted: 02-27-2007 12:49 pm
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edward_davis



Joined: 07-06-2005
Location: Eugene, Oregon USA
Posts: 162
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 If the heater valve breaks, it's most likely to break in the 'open' position.  It's operated by engine vacuum, and when there's no vacuum, its springs hold it open.  Si if it freezes after a long period of non-operation (Which never happens to Jensens, right?), it will be stuck open.  Also, if the vacuum lines are leaking in some way, it will be stuck open.

Steve, I'm sure you checked this first thing, but I just have to mention it because I've bypassed the leaky heater core on my JH.  Make sure that the PO hasn't bypassed the heater, with a sneaky loop of hose behind the engine; if it is, you might want to go ahead and tear down the console to get the heater core worked on, since it probably was leaking (hence the bypass).  If your hoses check out, and you don't have any blockages like Harkes, you'll probably have to tear it all down to get the heater core out, anyway.  They don't make them anymore, so you'll have to find some old-school radiator person who will rebuild it for you.  That's exactly why I haven't bothered with it yet.  I get enough radiant heat from the engine and exhaust, anyway....

 

Edward