Vacuum line unknown

[Stoffauge]

Hey guys ,

Can’t tell where the third vac line is going to get attached in the engine compartment . Vac diagram doesn’t show a third line going into the eng compartment .

On pic: upper one on vac reservoir
And the one below to the heater valve . But where does the third go to ?


71 sport fury 383 with AC

 

[ceebuddy]

Not sure but I think it attaches to the low-temperature cutout switch (or whatever it is) located on the outside of the HVAC housing in the engine bay.

 

[Stoffauge]

Hvac housing is the big black one on the fire wall right. Do you know where on that housing the nippel sits ?

 

[CBODY67]

Not sure if this is relevant to this issue, but on my '70 Monaco Brougham, I discovered a vac line with a piece of stranded wire in its end, coming through the firewall just above near where my right foot would be if I was sitting in the passenger seat. Seems like it had a green tracer on the black silicone-content hose. I was puzzled by it as it had nowhere to go, just laid there near the top of the carpet for the rh footwell. Wasn't hurting anything, but just nothing even close to it nor anything "uncapped" where it might need to be. The wire in the end puzzled me, too. Nothing was inoperative, either.

One day I was looking in the FSM and found a hvac picture of that area, with the two vac lines located just where they were on my car. The one with the "wire end" was labelled "Vacuum Bleed". The wording in the FSM explained it was a vacuum bleed (for a circuit i don't recall), which explained the stranded wire rather than solid. I guess it was an inexpensive way to engineer a very slight vac bleed situation. So I did not worry about it again as it was apparently as it should be.

Hope this might help?
CBODY67

 

[3175375]

Not sure if this is relevant to this issue, but on my '70 Monaco Brougham, I discovered a vac line with a piece of stranded wire in its end, coming through the firewall just above near where my right foot would be if I was sitting in the passenger seat. Seems like it had a green tracer on the black silicone-content hose. I was puzzled by it as it had nowhere to go, just laid there near the top of the carpet for the rh footwell. Wasn't hurting anything, but just nothing even close to it nor anything "uncapped" where it might need to be. The wire in the end puzzled me, too. Nothing was inoperative, either.

One day I was looking in the FSM and found a hvac picture of that area, with the two vac lines located just where they were on my car. The one with the "wire end" was labelled "Vacuum Bleed". The wording in the FSM explained it was a vacuum bleed (for a circuit i don't recall), which explained the stranded wire rather than solid. I guess it was an inexpensive way to engineer a very slight vac bleed situation. So I did not worry about it again as it was apparently as it should be.

Hope this might help?
CBODY67

It is indeed a vacuum bleed.
I went through the hvac system on my 69 Plymouth Fury III convertible and I used the FSM and a couple of other things including a YouTube video.
Look for my post on replacing vacuum actuators and the mode control switch.
I’ll respond later with the information when I come up for air.

 

[3175375]

Here’s the thread where I went through the mode control switch, time delay relay, actuators and the like:

Rebuilding the ac/heater control switch