1976 280Z vacuum selector valve

[Z Excellence]

When I select vent on panel the heat comes on. All vacuum lines have been replaced. I have traced the problem to under the dash heat/control panel. When I touch the vacuum selector valve it will cause other AC/ defrost / heat doors to open. Is there anybody that has one of these valves? Can’t find one anywhere. Thanks, Tracy

[zclocks]

You might try zKars on this site. He does a lot of work on Zcars and has a big stash of parts.

Ron 

 

[Z Excellence]

36 minutes ago, zclocks said:

You might try zKars on this site. He does a lot of work on Zcars and has a big stash of parts.

Ron 

 

Thanks Ron. I will

[zKars]

ZX part I believe. I have pretty much nothing ZX, just 70-78 Z

[Z Excellence]

No this is 280z with factory air. 1976. The drawing is out of 1976 280Z shop manual. The picture is in my car. 

[Zed Head]

Looks to me like the valve has the hose connection locations cast in to the back.  I would use those instead of the drawing if they don't match.  Looks like one your D hoses is switched with another spot, it's on the "I" position.  Don't lose those pieces of tape.

[Z Excellence]

24 minutes ago, Zed Head said:

Looks to me like the valve has the hose connection locations cast in to the back.  I would use those instead of the drawing if they don't match.  Looks like one your D hoses is switched with another spot, it's on the "I" position.  Don't lose those pieces of tape.

Thanks I will check that out. I see what you are talking about. 

[zKars]

aha! Just not something I’ve seen very often. I only have two 280 hvac control setups, neither were AC unfortunately, so no vacuum switches....

 

[zclocks]

Good catch Zed...

 

I have a 75 and this is what the manuals says . The "T" in the vacuum line  should be connected to the D1 on the vac switch , but is connected to I.

Edited October 30, 2020 by zclocks
photo

[Zed Head]

No comprendo.  Seriously.  Don't know.  When the label is right at the end of the hose, how can it not go there?  Can't hurt to switch them.  There is a lot of stuff in that AC chapter.  I think the 76 FSM chapter might be in better shape than 75.

This part here is odd also, below.  Not sure what it means.  Touch.

8 hours ago, Z Excellence said:

When I touch the vacuum selector valve it will cause other AC/ defrost / heat doors to open.

 

[Z Excellence]

When I pulled out the center console and with one hand I would touch the vacuum selector Lightly with my finger While vent was selected  it would cause air to come out different areas. For instance vent was selected but touching the vacuum selector made air come out of heater doors. I’m also puzzled by the shop manual has different stamping on the selector than my car. I’m the original owner. I was in Houston Tx so I had to put the console back in to drive it home. I agree with you that I should follow the stamping on the valve, not the shop manual. AC and defrost work perfectly. Thanks for your input and help. 

[zclocks]

The D1 and " I " looks like they are interchanged. I'm going to look at mine and mark them with my label maker. This is something else I have never seen. 

I will check mine out tomorrow and take a photo.

Ron

Edited October 30, 2020 by zclocks