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| | | | Joined: Aug 2012 Posts: 1,214 Shop Shark | | Shop Shark Joined: Aug 2012 Posts: 1,214 | I'll venture a swag. Inorder for the heater core to stay constantly hot, coolant must flow in and out. Which would seem to indicate one feed could be a suction side. Or at least a return to the pump. By shutting off the pressure or "in" side to the core 1st, The suction or "out" feed "may" draw coolant out before its closed.
What they are probably doing is keeping both sides closed keeping the core bone dry and never using the heater.
I dunno, just a swag. | | |
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