Item Subject: cc:Mail Text

     In line with the heater feed hose is a "plastic" valve which gradually
     wears and allows hot water to flow around the valving mechanism.  Easy
     fix from below requires new valve.

     Or it may be that your bowden cable (the wire gizzy that runs the
     valve thingy from that gizmo on the dash) isn't moving the valve.

     Have your pet move the slider while you watch from under the van.

     If the valve is closing all the way and leaking to to paragraph 1.

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