Does anyone have a diagram of the bottom of the heater selector valve (280Z with air) as seen looking under the dash? I'm pretty sure the PO got my stuff mixed up and I'm not getting vacuum to the right nipples. I get warm air blowing on every setting, but from different vents. It seems the intake door tube was hooked up to the vacuum **** port?

I made up a logic diagram for the nipples from the FSM, but I don't think the vac valve nipples are laid out the same as the FSM drawing.

thx a lot.

I made up this pic of what I noticed on my car. In the drawing, S and D2 are in the back ( nearest the firewall, and S toward the driver door) and D1 and I away from the firewall (I toward the pass. door.)

BTW, just having one ofthose little vacuum tubes open caused the idle to change, so make sure you get all tyose pesky vacuum leakes fixed!

thx

TomoHawk,

This might help you out some. I believe the connections should be the same up thru 78...You can use it for a wallpaper as well...() as it's in a BMP format...

webdawg1

Vacuum Hose Diagram.bmp

That's the one I saw in the FSM. It's possible that the hissing that's confusing me is a leak in the selector control.

thx

Water valves and vacuum! Just been there. Check that the vac line is connected to the top of the water valve, your problem won't be in the selector, you have somehow pulled a line off one of the vac operated servo's.

Good luck in tracking it down.....

Those old vac tubes were splitting which is why I was replacing them. AFAIKT, there are only nipples on the bottom of the selector, and having replaced all the tubes I could, there is still a hiss, and since I know the water valve is behind there somewhere, it could be that.

BTW- now the fan won't run. The switch has been buggy for a year or so. Switching on full-speed somehow disables the switch temporaily- I think the brushes inside were loose. I opened up the fan speed switch, and cleaned off the green crud from the brass contacts (steel wool & DeOxit 100) and the fan still doesn't go. I will see if I can put power direct to the motor & test that.

De Ja Vu....

Check the connector below the water ****. That had a habit of working loose. No connection and no fan. A good way to check electricals in the wiring loom and connectors in the creature comfort area is to check if you have illumination of the heater control panel. No lights ten you can bet a connector has failed.

HIH

MOM

thx mate.

Yeah, the heater illumination light works, but now the electric antenna has no power. I'll try your idea too. I'

ll even check the fuses...

I had a heater guy check out the vacuum hoses, and he was able to replace the leaky one in an hour, there was also a short in the wiring (PO spliced into the power wires) and I had to replace the 6blade connectorof the fan switch. After disassemnbling the fan switch & reassermbling, the vac tubes & connector, I get all the functions, 3 or 4 times the air from the vents & defrostor, but still get only outside air from the bi-level setting ( which sounds about right.)

thx

........but still get only outside air from the bi-level setting ( which sounds about right.)

thx

I believe that's a cable adjustment IIRC. It's been so long since I fixed that problem on mine.

Thanks, I"ll look into it sometime. higher repair priorities present themselves for now.