Heater vacuum lines on Zagato

[richarda]

Neither of my heaters worked on my zagatos so I decieded to work on them.

On my 82 I found that the line from the engine into the car was broken, I replaced it and now all seems to work with a couple of exceptions. The flap for fresh air stays open when on defrost, closed at proper time on other settings. Heat works. AC does not but I doubt that the system is up to par, in any case it would be R12 and I can live without.

On my 81 I found that the line from the engine to the inside was not even hooked up, got it hooked up and no line going to the hot water valve, replaced same and got the hot water valve to work. I can not get the flap to work correctly. I think that the yellow line from the that runs from the valve inside is not hooked up, I can blow into it and hear air coming out. But I don't know where this is or how to get to it. Also the fan switch is not working, I changed the wireing to one of the rocker switches so I do have a fan (high speed).

What is not working is the AC, (see note above) when you press the max air it does not seem to want to go in. The flap is not working as it should, all air is coming out of the defroster.


Questions
1) Is there a source for the fan switch?
2) Is there a source for a diagram of vacuum system?
3) On the line that comes from the engine both cars have a T, one going to the switch that allows vacuum to go to the hot water valve and the other going to ????????
4) Where does the yellow vacuum line go? and can one get to it?

Any help is welcome:)

[davidb]

I just went thru this Richard so here goes. Di Fatta may have a
NOS CEAM switch. Unless yours is mechanicaly broken I would
suspect wiring or the fan motor. Your diagram is here in down-
loads: '79 A/C Helper Card. Two fabric coated vacumn hoses:
one from the heater valve [firewall], 2ND from vacumn canister,
both go thru firewall under fusebox. They snake WAYYYY up hi
inside over the heater-A/C box behind where the radio resides.
I replaced both hoses. Your colored hoses should be okay. W/
driver kickpanel removed [figuratively] raise your right foot up.
The vacumn tee is in this vicinity. On your back look straight up
into that mess of wires. The colorcoded vacumn hoses are on the
tee "run". The black hose is on the tee branch [inlet]. Sometimes
the colorcoded hoses are substituted color-wise. Yellow instead of
green, etc. No sweat if things work. Make sure your cold-to-hot
cable bracket [slider bar] above the HVAC pushbuttons is secure!
It LUVs to loosen. That slider bar is vacumn controlled so w/the
engine off [zero vacumn] move it SLOWLY! I could babble on but
this will give you some help [I hope]. W/the A/C Helper Card &
lots of patience you'll make progress. Get back to us.

[OperaHawk]

Along this line, another Q:

I converted my AC to R134, and it's been working quite well until about a week ago - no cold air. I figured that it was probably low on coolant (it takes an old R12 system a couple of charges to hold a 134 setup), so I fired up the engine and placed a hose with a pressure gauge on it. The system is in the red - WAAAAY up in pressure. I tried putting more coolant in, but it won't take it.

So MY questions are:

1) What caused this?
2) Can I just bleed the system and refill it?

SBJ

BTW - Jim, check your personal messages.

[davidb]

I'm of the opinion if you want the A/C to work pull the exchanger
in front of the radiator, flush it w/wood alcohol, blow it out. Gets
rid of all that nasty whiteish/yellow milky ancient crap. Comp-
ressor? New SD-508s are reasonable, $250 something. A new
drier would help too. Hoses for the new compressor too [I for-
got that part]. Lotsa sensors which might have failed too. Jim
will likely differ in his suggestions. Of course pressure test the
clean exchanger before replacing it. I've made that mistake.

[Jim Keller]

If it's way up in the red, it may just need bled down to proper pressures. It has a pressure switch to keep the compressor from operating and seizing up if the pressure gets too low, maybe it also works for pressures too high. Don't forget to use the temp charts when reading your gauge as well, outside temps drastically affect the pressures and gauge readings so you need to make sure it is at the pressures that coincide with the ambient temps

So in other words, yes, you should be able to bleed it down and re-fill to proper pressures, or just bleed it off until you get the pressures lowered to proper settings