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defroster won't work?
https://www.slantsix.org/forum/viewtopic.php?t=31479		 Page 1 of 1
Author:  plymouthhillsidehemi225 [ Fri Oct 03, 2008 9:07 pm ]
Post subject:  defroster won't work?
I removed my A/C compressor on my 78 Volare, redneck style and just cut off and plugged the hoses, just to get that junk out of my way, but now my defroster won't work... ???
Author:  THOR [ Fri Oct 03, 2008 10:23 pm ]
Post subject: 
What exactly do you mean by defroster? Simply that the air isn't directed to the top vents? Is it the fan that won't come on? If the fan works, I would suspect that you have disconnected (plugged) the vacuum line(s) that turns the vents to the "defrost" position.

The "defrost" selector on the panel should also deactivate the A/C compressor, so I would start tracing the hoses from the defroster selector, and follow them using a manual. Even a Haynes manual should have the schematics for vacuum hose routing, for A/C and non-A/C cars. You would obviously need to follow and hook up according to the non-A/C schematic.


~THOR~
Author:  '74 Sport [ Thu Oct 09, 2008 11:40 am ]
Post subject: 
If your Volare has a water control valve like my Dart and Duster, make sure it works properly. The vacuum line from the heater control switch will operate the water valve, allowing circulation of hot coolant through the heater core. Otherwise, the blower fan will only circulate cool air, not conducive for clearing fog.

Jerry
Author:  plymouthhillsidehemi225 [ Thu Oct 16, 2008 7:42 pm ]
Post subject: 
ok, I'm really not smart at figuring this type of thing out but my fan works just fine, heater works, I just can't get it to come out the defroster ducts when I push the defroster button... I just got done super sixing it and not all the vaccum hoses had a place to hook up to so...
Author:  '74 Sport [ Fri Oct 17, 2008 6:28 am ]
Post subject: 
Sounds like the door in your heater box that is supposed to redirect the heated air is not working properly. You either have a leaking (or missing) vacuum line, faulty A/C-heater control switch in the dash, or faulty vacuum actuator (?) that has a diaphram pod and link arm attached to the defrost door.

Anyone have a '78 Volare vacuum line routing diagram he can look at? I would start by checking all around the A/C - heater box for cracked, loose, hanging, or missing vacuum lines. Then trace all the lines you do see all the way back to the control switch in the dash, making sure they are all hooked up. Sometimes the switch may have some of those little plastic nipples broken off where the vacuum lines attach.

All of this is, of course, assuming the controls are vacuum operated. If they are cable operated, instead, then forget everything I just said. :roll:

Jerry
Author:  volaredon [ Fri Oct 17, 2008 6:41 am ]
Post subject: 
thats strange, as the "default" mode in every vehicle I have ever had is defrost; leave off the vacuum line from the engine that goes inside the dash, and no matter which buton is oushed (other than "off") thats the ONLY place the air will come from. And "off" don't change the position of the air doors in the plenum, just kills power to the blower motor. If the vac is unhooked from the control in the dash, or that switch goes bad (I've had a few) it still defaults to defrost mode, maybe SSDan can chime in and add to that thought.
Author:  plymouthhillsidehemi225 [ Fri Oct 17, 2008 7:57 am ]
Post subject: 
ok I did some looking and found a what I think the vaccum hose is (a really small pink tube coming through the firewall in the general area of the heater controls) and I'm pretty sure that's the problem, but I don't know what its supposed to hook up to in the engine compartment?
Author:  Charrlie_S [ Fri Oct 17, 2008 9:34 am ]
Post subject: 
On these cars the heat/defrost actuator is double acting, there is no "default" position. It can be in either heat, or defrost, if vac is lost. There should be two small vac hoses in the engine compartment. One (gray) goes to the hot water valve, the other is the vac supply. It sounds like this is not connected. This should be violet, and connect to the to the vacumm tree in the number 6 intake runner. There is supposed to be a small (about the size of a dime in diameter) check valve in series with the violet hose and the intake manifold. The hose between the manifold nipple and the check valve is black.
Author:  plymouthhillsidehemi225 [ Fri Oct 17, 2008 11:12 am ]
Post subject: 
ok that's what I figured where its supposed to hook up to, but the problem is is that that nipple on the intake that also goes to the master cylinder is now just a simple one going to the brakes... without a little nipple for this hose... is there a different place I could hook it up to obtain vaccum?
Author:  plymouthhillsidehemi225 [ Fri Oct 17, 2008 4:32 pm ]
Post subject: 
ok, I just figured it out, I took and teed into the little vaccum hose coming off the carb going to the air cleaner with my little pink hose from the heater controls... now everything works fine... thanks for the help
Author:  THOR [ Fri Oct 17, 2008 8:20 pm ]
Post subject: 
Yup... that's what I would have done. Depending on the carb there may be another spot you can hook it up.. if you so desire.

~THOR~
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