PetesPonies Posted September 15, 2017 Share Posted September 15, 2017 Do the non AC heater controls work by cable and the factory AC/heater controls operate by vacuum? ( Again mine is an '82 ) Link to comment Share on other sites More sharing options...
Gary Lewis Posted September 15, 2017 Share Posted September 15, 2017 That's my understanding, although I've never had one w/o factory A/C. Okiehoma is hot in the summer! Link to comment Share on other sites More sharing options...
PetesPonies Posted September 15, 2017 Author Share Posted September 15, 2017 That's my understanding, although I've never had one w/o factory A/C. Okiehoma is hot in the summer! Well my '83 Bronco was a dealer added AC supposedly. It has cables operating the doors. I see this '82 has vacuum. The selector door is not operating . . . so is this common? bad diaphragm or just vacuum split or loose lines? Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted September 15, 2017 Share Posted September 15, 2017 Well my '83 Bronco was a dealer added AC supposedly. It has cables operating the doors. I see this '82 has vacuum. The selector door is not operating . . . so is this common? bad diaphragm or just vacuum split or loose lines? Start with the vacuum line coming from the junction manifold on the cowl into the cab by the heater core. That is the one that gets baked and marinated in fumes in the engine bay (and the one most likely to fall apart) If it looks good then pull the heater control and check for vacuum there. Link to comment Share on other sites More sharing options...
kr98664 Posted September 16, 2017 Share Posted September 16, 2017 Do the non AC heater controls work by cable and the factory AC/heater controls operate by vacuum? On factory AC trucks, the heat blend (hot/cold) door is cable actuated by the upper lever. The other doors (recirc, defrost, floor, and dash face) are vacuum actuated by the bottom lever. Karl Link to comment Share on other sites More sharing options...
kr98664 Posted September 16, 2017 Share Posted September 16, 2017 The other doors (recirc, defrost, floor, and dash face) are vacuum actuated by the bottom lever. This forum software is enough to drive a guy crazy. Having trouble editing my previous post and my second response has gone missing. Re: The vacuum operated doors. There are three of them, not four as I was thinking. A single door (not two) switches between defrost and floor. Recirc Floor/defrost Panel (Dash face) First illustration here has more details: https://www.ford-trucks.com/forums/1486377-how-to-repair-the-ac-vent-door-hinge.html Link to comment Share on other sites More sharing options...
kr98664 Posted September 16, 2017 Share Posted September 16, 2017 I see this '82 has vacuum. The selector door is not operating More details, please. Define "selector" door. There's a single temperature blend door (hot/cold), cable controlled by the upper lever. The bottom lever operates three doors by vacuum: Recirc Floor/defrost Panel vents More details here: https://www.ford-trucks.com/forums/1486377-how-to-repair-the-ac-vent-door-hinge.html Link to comment Share on other sites More sharing options...
PetesPonies Posted September 16, 2017 Author Share Posted September 16, 2017 I see this '82 has vacuum. The selector door is not operating More details, please. Define "selector" door. There's a single temperature blend door (hot/cold), cable controlled by the upper lever. The bottom lever operates three doors by vacuum: Recirc Floor/defrost Panel vents More details here: https://www.ford-trucks.com/forums/1486377-how-to-repair-the-ac-vent-door-hinge.html The selector door is what the door that changes where the air goes is called. You are selecting the position. Link to comment Share on other sites More sharing options...
PetesPonies Posted September 16, 2017 Author Share Posted September 16, 2017 The selector door is what the door that changes where the air goes is called. You are selecting the position. That's a good description of how to remove the hinged door. Mine is defaulted to the defrost, so that is probably the culprit. I'll verify vacuum first. I turned a heater core removal on a Cherokee once, from a 6-8 hour job to about 1 hour . . .but making a couple cuts here and there. Once it was all reassembled, it looked OEM. Link to comment Share on other sites More sharing options...
kr98664 Posted September 16, 2017 Share Posted September 16, 2017 The selector door is what the door that changes where the air goes is called. You are selecting the position. Not sure I'm getting through. Don't mean to insult you, but I don't want you fixing things that aren't broken. There is more than one door in the system. There is NO single "selector" door. Three separate vacuum-operated doors work in series to route air as commanded. A fourth door (cable-operated) controls hot or cold, but let's skip that for now. Here's how air flows. Go to that first illustration at the hinge repair link for more details. Air is drawn into the plenum by the fan. The first vacuum-operated door (recirc) controls whether air comes from outside or inside. In the event of a loss of vacuum, this door actuator is spring-loaded to the outside (fresh air) position. The next step is the temperature blend door. This is the cable-operated door. For maximum heat, all air goes through the heater core. For no heat, all air bypasses the core. The door can be positioned anywhere in the middle for heat control. Next step is the panel vent door. With vacuum present at the actuator, ALL air flows to the four registers on the face of the dash, AND the passage to the defrost and floor nozzles is blocked. With no vacuum at this actuator, it's spring-loaded to send all air downstream to the defrost or floor nozzles, and none to the panel vents. Last step is the floor/defrost door. Remember, the panel vent door actuator must be relaxed for any air to reach this last door. The floor/defrost door simply routes air up to the defrost nozzles or down to the floor. This actuator also has a mid position to route air to both the defrost and floor nozzles. For a loss of vacuum, this door is spring-loaded to the defrost position. You mentioned having only defrost available. That would point to a complete lack of vacuum, as previously suggested. Start there, and make sure you have engine vacuum reaching the dash selector switch. After that, check the vacuum outputs from the selector switch to the individual actuators. Just don't go looking for that one mythical "selector" door, cuz there ain't any such thing. Hope this helps. More details here: EVTM Link to comment Share on other sites More sharing options...
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