AC Hose to Passenger Vent

[springer12]

I am working on reconnecting the AC on my '78 SC. I have the hoses connected to the driver side vent and the central vent but can't figure out the passenger side. Coming off the evaporator there is a connection that goes into the cabin facing the passenger side but the vent on the passenger side seems to connect from within the trunk. Question is how does the connection going into the cabin get to the passenger side vent?

[DRACO A5OG]

From inside the cab up from the penlum and "Y" into the heat pipe then to the side vents. Yeah really crappy design, was not better improved until '86. The pre86 just whispers cool or hot air to you. Actually my driver side works better, if you can call it that.

[kuehl]

pic a numba

[springer12]

Thanks, PET didn't really help as it doesn't show where or how the line connects.

It shows the line comes off the evaporator and goes into the interior. Draco you mentioned it is meant to go through the interior. Still can't seem to figure out how it goes from inside the cabin back to the trunk to connect to the line on the passenger vent. What am I missing?

[DRACO A5OG]

#43 and #38 (Hoses) connect to #40 (Y) then #44 (hose) connects to P-side Vent.

You may be missing the Y, if so get a copper plumbing Y divertor at your local ACE. There are plastic ones but they do not hold up well to the heat

That hole/port in your frunk pic is not used

[springer12]

Hmm, the hose I have coming into cabin is labeled #13. Looking at hose #8, it connects directly into the driver side vent. I believe #13 must connect directly into the passenger side. Do the small side vents get heat or just AC? If they get both, I don't understand how #13 and #8 connect in to allow for heat. Tempted to just run #13 to the vent and call it a day.

[DRACO A5OG]

You sure can, but no heat will get to that p-side vent.

The diagram shows two methods:

#43-44 connect via 39-40 up from foot blower motor ( 3.2s ), AC, Heat and Fresh air

vs

Just #13, direct feed no heat or fresh air

[springer12]

That is very helpful. I didn't get that the diagram was showing two options so that was what had me confused. I do not have parts 35, 36 or 40 so it must be that mine was directly connected AC only. Thanks for helping me figure this out!

[DRACO A5OG]

You are most welcome, So circa '78 does not have heat at foot wells? Strange.

[OttawaDave]

Originally Posted by springer12

I am working on reconnecting the AC on my '78 SC. I have the hoses connected to the driver side vent and the central vent but can't figure out the passenger side. Coming off the evaporator there is a connection that goes into the cabin facing the passenger side but the vent on the passenger side seems to connect from within the trunk. Question is how does the connection going into the cabin get to the passenger side vent?

Hey folks - apologies for reviving a super old thread, but I'm looking for a bit of info on the tube shown in the OP's second photo in his initial post...in my car, that open tube was capped with a type of clear rubber cap which, after 40 years has basically disintegrated.

My car is an '85 which to my knowledge was unmodified in this space. I don't see any open/disconnected tube anywhere else that this would connect to, so I'm unsure if there is a missing hose here, or if I should just find/fabricate a new cap to keep critters out of that now open passage. Maybe this was set up for some optional HVAC feature?

Thanks in advance!

[EC900]

On a Non-AC car up to 1985 that port would have a hose connected that direct heated air to the small vertical side (window) vents at each end of the dash.
Good to close it off. There are slip-on chair leg caps that would work, available at home depot etc.

[OttawaDave]

Perfect - thanks very much!