Need help with heater hose and control valve install

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Hi tpj71mach

I looked at your original picture. In addition to the valve, you will need the Vacuum Reservoir Canister for the heater part of the system to operate properly. You should have 2 loose vacuum hoses on the firewall under the hood. 1 for the Vacuum Reservoir Canister and 1 for the valve.
Thanks, I have the vacuum tank and the vacuum line installed, I appreciate the heads up.

Mach 1 450a.jpg
 

73CobraJet

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Hi tpj71mach

I looked at your original picture. In addition to the valve, you will need the Vacuum Reservoir Canister for the heater part of the system to operate properly. You should have 2 loose vacuum hoses on the firewall under the hood. 1 for the Vacuum Reservoir Canister and 1 for the valve.
Oh great!! Looks like I might need to find some more parts! Any Idea where to search on the car for these vacuum hoses?
 

351c1971

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There should be 2 vacuum hoses in the middle top of the firewall. One goes to the vacuum canister and the other goes to the valve. These 2 vacuum hoses likely go to the rubber vacuum hose block on the back of the center console ac/heat controller

You will also need a vacuum hose from the intake manifold vacuum tree to the vacuum canister. These hoses show in the under-hood vacuum diagram from Hemi Killer in the beginning of this thread.
 

nursieee

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The heater valve is not attached to anything other than the end of the "S" shaped molded hose from the heater core. See the attached pix. The white nylon clip is a cable clamp from Home Depot.

Hi All,

First off, I'm sorry I originally posted this thread in the concourse section.

I am starting the install on the heater hoses and I have a few questions (here is where my lack of Ford experience kicks in). I realized that I do not know the flow pattern between the heater core and the water pump and block ports. Also, I am trying to buy a heater control valve and NPD has one without a bracket and has arrows indicating the flow can go in either direction for this valve. Unfortunately, this valve has been out of stock for the last month and they told me on the phone they do not know when they will get more in stock. CJ Pony (not my first choice for suppliers) has one but there is only one arrow cast in the case of it which seems to indicate the flow can only go one way, and this valve has a mounting bracket. Can someone please tell me which style of valve is correct for my 71 Mach 1 351C with A/C? If it is the style that NPD offers, does anyone know where I can get that style without waiting for NPD to get it back in stock?

Hemi Killer posted a great diagram (see attached) of the routing in a different post I found on heater hose routing which was very helpful in the routing aspect, but the drawing overlaps the two hoses as they run along the intake manifold. I am unable to determine for sure which hose is which from the engine end to the heater core end. It appears to me that the water pump outlet hose is the one that has the control valve in it and it is attached to the inboard port of the heater core and the hose attached to the outboard port of the heater core runs directly to the nipple in the block, is this correct? If it is, am I correct in assuming the flow runs from the water pump through the control valve and on to the heater core and then returns to the block? If this is the correct flow pattern then it appears that the CJ Pony valve's one way flow is backward to the bracket orientation. Where the bracket could be mounted on the intake the flow arrow points the opposite direction. It does look like the valve and bracket could be swapped around to work though. I appreciate any help I can get regarding the flow and the correct valve style and if anyone has used either of these valves themselves. Thank you

View attachment 70758 View attachment 70759 View attachment 70760 View attachment 70761 View attachment 70762
I dont really see which pipe to attach the hose coming from the right heater core pipe on pic 3.
Does it attach to the right pipe also? (standing in front of car looking to firewall).
 

Hemikiller

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I dont really see which pipe to attach the hose coming from the right heater core pipe on pic 3.
Does it attach to the right pipe also? (standing in front of car looking to firewall).

The outlet tube in the block is connected to the lower of the two heater core tubes. The inlet on the water pump is attached to the upper.

The water control valve is in the return hose according to the diagram.


1675963169356.png
 
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