Its been over 100 degrees lately and inside a 1954 Sun Valley on a sunny day it can get mighty warm.  The left vent is open and on my last cruise I was feeling below the dash for cooler air and realized that there was HOT air coming through the heater, even though it was supposedly off.  The right hand air/heater control cable is broken but the other cables and controls are operating correctly.  I have manually closed the right hand air intake so there is no air coming into the heater nor into the cabin.  The vacuum operated water control valve on the engine is new as well as the vacuum line to the heat control switch.  The heater hose from the water control valve goes to the top tube of the heater at the firewall.  The heater hose from the water pump goes to the bottom tube.

Question 1:  Are these hoses at the heater reversed?  Logic suggests that water should flow from the water pump to the top of the heater core and the return flow should go out the bottom and back to the control valve.  But if that were the case, hot water would always be in the heater.  So, Captain Obvious would say that the water flow is from the intake back to the water pump which apparently would be an inlet rather than a discharge.  Maybe I solved this myself which brings me to question 2.

Question 2:  How do I check the heat control switch?  Mechanically it functions with the control cable which is supposed to route vacuum to the water control valve.  What should the vacuum be at the control switch and at the control valve?  And, how can I determine that the switch is controlling vacuum, how can I tell if the water control valve is working, and how can I tell if water is not flowing to the heater when the heater control levers are in the OFF position?  Darn, that even confused me ! !  Any help?

Question 3:  I mentioned earlier that my heat/vent cable (right side) is broken.  Does anyone have one they would part with?    FDC 700 1890 A    approx. 79 3/16 long - 1954 only