Heater controll valve and flow question.

[68fe360]

I have a 1968 F100 360fe with a NP435 from a 1975 f250 that replaced the 3 speed.

My heater controll valve corroded to the point of spraying hot green stuff every ware. The replacement the local parts store had was a plastic repro unit. They asked which direction the flow was. Well like I said mine was crusty. If there was a directional arrow on the outside, it's no longer there. Just a big rusty hole. Lol

I think I ended up with the incorrect one. The directional flow of this replacement valve is towards the heater core. Is this the correct one for a 1968 360fe setup?

Even with the valve closed the heater core is heating up, and the small amount of ventalation air that is normaly allowed through serves as heated air. Which is no big deal when it's -10 outside. I have it on defroster mode all the time in the winter anyway. But during the summer this sucks big time.

A directional valve will leak if installed backwards. Which has lead me to believe that I have the wrong one, and hoping to verrify this. As I hate antifreeze on my hands, and already drained the radiator twice in the last few weeks while installing an aluminum radiator, and fan/shroud combo. If I don't have to do it again so soon, I don't want to!

The bypass that comes from the water pump leads to a T junction that runs to both the heater core and the de-icing spacer under the TBI. It exits the front of the spacer then hits another 2 way connector on the intake the exits towards the heater controll valve. Which exits the valve and enters the heater core on the right side. The valve's directional arrow points towards the heater core. Hope that helps. If needed I will try to get a picture. I did my best recreating the hose areangement. I replaced the hoses while replacing the valve for cheap insurance against future leaks. Maybe I buggered the routing of the hoses, but don't think. The old ones were still in place, and pretty easy to recreate.

[Johnnewc]

Try this part number if this is what your are looking for. (C3UZ-18495-A)

[390FE1972]

Here is some images and diagrams that show the hose set up with the temp control valve:

http://www.fordification.com/images/70explpics/17.jpg (1970 Ford F100 with 358 miles on it, 360 engine)
http://www.fordification.com/tech/image ... tegral.jpg (click to enlarge) (Tech image showing hose set up with temp control valve)
https://www.npdlink.com/product/control ... 0376/50792 (replacement part like OEM from NPD, image shows bottom of temp control valve). It is my understanding that the hot antifreeze goes through the hose to the temp control valve, which you can switch off with the heater select switch in your cab, if you have the temp control switch open to flow, it goes through the heater core and then back to the engine.

Hope this helps

[68fe360]

Great! Thanks for the help guys!

From the pictures it looks like I do have the correct directional valve. Even though it's one of the plastic repro's. Plus I did get the hose routing correct.

What I did notice after taking another look is that I added a few extra inches to outlets hose. Due to the original bracket that holds the houses having corroded, or lost by a previous owner long ago. It is sagging way low and close to the exhuast manifold. This is likely heating the house up. Letting hot coolant to flow back into the heater core due to heat convection. Since there is no valve in the outlet side.

So I will try using some zip ties to hold the hoses up and out of the way, and see if this makes a difference. If not I will assume the cheap plastic repro valve is leaking pretty bad, and replace it with a quality one from D.C. Sometimes a few extra bucks is money well spent.

[68fe360]

Looks like the plastic valve is just crappy and most likely letting hot water through. Even after keeping the hoses out of the way it continues to heat up while the valve is in the closed position. Since winter is coming, I will make it a spring project.

I never like using the heater in car or truck. They make things to hot which puts me to sleep. I just the defroster, and open the window to help controll the temp. A warm day in the winter for us is 35F. So no big deal to wait until Spring,

[390FE1972]

Thanks for updating us on this.

Regards