Heater Control Valve--which hose?

[69 Rustang]

I am trying to prepare my 73 to get the A/C functional again and have installed the heat control valve in the heater hose. I can still feel some heat coming out of the vents with the temperature setting on "cool".

My question--which hose going to the heater core does the control valve need to go in or does it even matter? Or maybe a better question is which line off the engine should have the valve in it? If it helps--I am running a 351C.

Thanks for any help!

 

[bnickel]

i need to find this one out myself.

 

[grainboy]

The hose hooked to the water pump would be the pressure line. That would be the one to put the valve in. The other would be the return, and shouldn't draw much heat.

 

[69 Rustang]

One of my Christmas presents answered my question for me. According to the 1969 shop manual, all the V8's show the control valve in the hose from the intake/top of the block to the heater core, not in the line from the water pump. FYI to anyone who cares.

 

[Max Power]

The hose hooked to the water pump would be the pressure line. That would be the one to put the valve in. The other would be the return, and shouldn't draw much heat.

I believe it can actually be used on either hose. It's a simple on/off butterfly valve, and warm coolant won't flow through the core unless it is open. The valve is not controlled by heat, it is controlled by cable or vacuum line from the heater controls inside the car.