Which heater control valve?

[my5thmopar]

The heater control valve was missing when I got my 72 Dart Swinger with a 318 a/c. It has the vacuum reservoir and the two hoses coming out of the fire wall. Is the valve normally open or normal closed. I haven't got the engine back in yet, so i cant just test to see when the vacuum is there. Anybody know? Also I'm looking here to order one, unless someone has another suggestion. http://bouchillonperformance.com/BPEheaterValve.asp

Craig

 

[Mr Hemi]

Are you talking about the water control valve? it is open with no vacuum to it

 

[my5thmopar]

Yes, I would have thought it would be closed??? I guess I'll wait until the engine is back in and working then I'll test it. It is cold here in TN now and it wont matter until summer anyway. Thanks.

 

[RedFish]

The 67 to 72 water valve has no spring in its vacuum servo so it's really neither N/O or N/C.Thus it's dual direction vacuum supply.
Lack of vacuum and presence of water pressure would result in N/O condition.
The last NOS replacement I saw was 135.00
The simple solution is to use an alternative valve that is spring loaded to N/O position and use a single and correct vacuum supply line to close it. You'll have one extra vacuum line to dead end and tuck away. Or Tee it into the resivoir line might work too.
I've got 2 used water valves and both leak water. They have been stripped down and bead blasted. My plan is to replace the water seals inside.
Soldering the valve back together without destroying the seal wont be easy. I'll probably hire a master plumber with experience in such things.
Hope this helps and good luck. Let us know what works for you.

 

[my5thmopar]

Thanks, I'll put this on my long list of things after the engine is back in.