In my research I have discovered there is a Vacuum Controlled Heater Core shutoff valve, yeah, it’s gone.
I have surmised the small hose sticking in the big hose in the above pix is the Vacuum Control line for the valve(it has a screw in it). Where does the Valve go? is it bolted down somewhere? or does it just hang there?
If someone would post a correct installation pix with heater hose routing I would sure appreciate it.
Here’s how the heater control valve and hoses are routed:
P.S. I have a lightly used heater control valve and S-hose if you want them for a few bucks+shipping (the ones pictured). But it looks like you have a 69 which is a different style than 67-68s.
Thanks for the Pix, My 69 doesn’t have the bracket that you valve sits on. the pix I’ve found for the 69 valve looks like it just lays on the intake manifold, which seems weird to me.
Still trying to figure out if I need the S tube hose or not.
I see you have the export brace…nice
EDITED: I deleted the attached file it was not correct for the A/C vehicle. The pictures and heater valve below are correct.
The 70 hoses were run as shown below. Can’t guarantee the 69 is the same but more likely than the 68. The heater connections at the firewall match with the 70. I recommend getting the Ford Service Manuals for you year. They can be very helpful. They are available in both hard copy and as searchable pdfs.
The 1969 ( not sure about the 1970, but I would suspect that it did not change ) hot water valve ( cut-off ) in fact does just “sit there” - there is no bracket for attaching the valve to. The valve itself doesn’t have any attachment points in its construction. It is positioned on the hot water inlet line, going into the heater core, approximately 2/3 of the way down the intake manifold side of valve cover. I believe that there is some sort of suspending bracket ( from just under the choke housing ? or coming up from one of the bolts that secure the valve cover ? ) to hold the hoses in position, so that they don’t drop down onto the manifold.
Here are a couple of images of the valve itself.
First is the original, all metal style ( engineering # on the part itself is : C9AA-18495-D
This next image is the Service replacement version ( D4AZ-18495-A / YG-136 ), and it is different in that part of the tube that inserts into the heater hose is now made of plastic.
Here is an image of the engine bay with the hose routing ( 1969 Mustang 351 V-8 ) and you can clearly see the position of the hot water valve and the two S-tubes.
And lastly this is the S-shaped ( molded ) heater hose piece required to connect the heater core to the main hoses. You need 2, one for the inlet and another for the outlet. Part # is C9ZZ–18472-A. Not uncommon, as they come up on eBay regularly ( 40 - 60 $ )
It would appear that the S-tubes are required for the 351 and definitely for the big blocks ( 390 and 428 ) as the clearance is insufficient to allow the heater hoses to dip down the back of the engine, for their connection to the heater core. If you try to force the heater hose down this confined area, you run the risk of kinking and restricting or completely closing off the passage of coolant to the core.
Thank you for the diagrams and the knowledge, deeply appreciated. As to needing two of the “S” hoses, I’m thinking only one, since the heater hose kit from WCCC has a bend in it already and would go on the discharge side of the Heater core.
