Vacuum water valve

Wollfen

Old Man with a Hat
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The 1969 to 1971 C cars use a vacuum operated heater control valve that looks like the picture below. I tried opening my service manual on my CD but the CD isn't working so I want to pick the brains of others here in the short term.
Here is the question, does the valve need vacuum to keep it open, or does vacuum shut the valve?

H1949.jpg
 
The 1969 to 1971 C cars use a vacuum operated heater control valve that looks like the picture below. I tried opening my service manual on my CD but the CD isn't working so I want to pick the brains of others here in the short term.
Here is the question, does the valve need vacuum to keep it open, or does vacuum shut the valve?

View attachment 89979

IDK, but based on my experience of newer cars, vacuum would be used to close it so the system could equalize when off. My guess is that means its probably backwards for that one.
 
IDK, but based on my experience of newer cars, vacuum would be used to close it so the system could equalize when off. My guess is that means its probably backwards for that one.
Yep!
Vacuum opens, no vacuum closes.
 
Alrighty, I was really hoping the vacuum shut it off, as while I have a vacuum leak which continues to elude me after much searching, I can say that once that problem is licked,
I can stop the heater cooking me on a hot day!
 
The 1969 to 1971 C cars use a vacuum operated heater control valve that looks like the picture below.
View attachment 89979
What you have there looks like an Everco H1949 to me. It works, but it is not what was used originally (on A/C cars). I also found that with the Everco unit it is not that easy to dial in your desired temperature since mine had more like an "not-yet-not-yet-not-yet--hot-hot-hot" action. At least in conjunction with my Fury's temperature lever.
I'd say the original crackpot valves work somewhat smoother. But we all know they are not cheap and probably won't hold forever.
18-H1949N_WM.jpg
 
You can grab a PDF of your FSM here: MyMopar - Mopar Forums & Information - Service Manuals
Then you don't have to screw around with the CD.

As was posted above, that's an aftermarket valve you show. My experience with them is they last for years and then fail with the valve open.

I found another aftermarket valve on Ebay. Some seem to think the plating on the outside is real gold, so they price them like it is. It took me a while to get one at the price I wanted to pay. In the meantime, I put a ball valve in the heat hose in it's place.

I haven't gotten around to replacing the valve (winter project!). I may leave the ball valve inline just to provide a positive shut-off so my A/C works to full potential.
 
Alrighty, I was really hoping the vacuum shut it off, as while I have a vacuum leak which continues to elude me after much searching, I can say that once that problem is licked,
I can stop the heater cooking me on a hot day!

My Fury had no valve and the heater core was always hot so I stuck this valve in for the time being.
20160625_204712.jpg
 
Where did you get that valve? It looks small enough to not be noticeable.
 
You can grab a PDF of your FSM here: MyMopar - Mopar Forums & Information - Service Manuals
Then you don't have to screw around with the CD.

As was posted above, that's an aftermarket valve you show. My experience with them is they last for years and then fail with the valve open.

I found another aftermarket valve on Ebay. Some seem to think the plating on the outside is real gold, so they price them like it is. It took me a while to get one at the price I wanted to pay. In the meantime, I put a ball valve in the heat hose in it's place.

I haven't gotten around to replacing the valve (winter project!). I may leave the ball valve inline just to provide a positive shut-off so my A/C works to full potential.
Every 1971 fury I have seen has the unit as I have shown in the top picture also,
The Parts Manual shows this, check the pic, I wonder if someone has a totally original unmolested 71 fusey?

H1949-1.jpg
 
My Fury had no valve and the heater core was always hot so I stuck this valve in for the time being.View attachment 90232
I have been thinking that at some time I may convert the vacuum unit to a manual control unit, it wouldn't be too hard as routing a cable can be done discreetly and the lever that actuates the vacuum unit at present could be modified to do a cable so nothing changes in the dash area.
 
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