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I found the wire that had corroded and seperated and caused my fan to stop blowing. Spliced in some 14ga wire and now it blows, but I think I have a stuck door/flap in the duct work, because the dash vents don't blow air. I only have the defroster and floor vents that cool.

Does anyone have, or know where I can find, a diagram of the ducts so I can check the components inside? Thanks!
 

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check the hoses that connect to the bottom of the dash vents from the heat/ac box first. some of those hoses are cloth/spring, and some were flexible aluminum tubes. the aluminum was real thin stuff. either one is easy to tear/damage (especially being so old) so that the air doesn't flow thru to come out the vents, so check those first.

:poke:
 

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usual issue with no dash vent is no vacuum. Check the vacuum ball under the hood to be sure it is connected, then check the purple line that goes under the HVAC in the engine compartment. They get brittle and break.
 

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still working on it

Under the hood all looks good.BTW,My big ball hass only on hose.The canister next to it has 2.1 to carb one to hvac...The control with all the hoses connected is turning fine...I have the whole dash apart because I'm installing a new dash cap...I can't seem to find where any hoses to the vents are....I really dont see the vent work tubes either...Where exactly is the blend door,if there is one???If I hadn't had the a/c working correctly,I'd think the vents were for looks only..When I took the center trim piece off,I was able to see what I guess is the air tube off to the left,towards the drivers side.Softa comes up to underside of dash but to the left of the vent...The drivers side I can't see anything..The whole vent is out but there is so much stuff I can't see.I have a feeling that my problem is some where on the drivers side...Might have knocked vacuum tube off when taking out parking brake handle.....On the vaccum diagram it shows a blue gong to left..can't find it...any help would be welcome...I'd really like to get this fixed before I put the dash back together....:dontknow:
 

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Behind the glove box, up high on top of the black HVAC unit. You will see where the cable comes from your HVAC control to a pivot bellcrank. Attached to the other arm of that bellcrank is a rod. The other end of that rod attaches to the blend door. As you move your temp cable on the HVAC controls, the bellcrank is turned, pushing the rod in or out. That moves the blend door. The blend door mixes hot air from the heater core with cold air from the HVAC unit.
 

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Might have knocked vacuum tube off when taking out parking brake handle.....On the vaccum diagram it shows a blue gong to left..can't find it...any help would be welcome...:
Don't know if you got this answered yet. You have two vacuum lines that come form the engine to the HVAC unit- one purple and one grey. The purpoe one is your supply of vacuum, which is needed to move the air to the required vents. The grey is vacuum back out to the Heater Control Valve on the Heater lines, to stop the flow of hot water under certain conditions.

Coming off the HVAC contro unit you should have a bundle of about 4 hoses ( different colors). Orange goes to the Recirc Door ( directly behind the glove box) Red, Yellow and Blue all connect on the left (drivers) side of the HVAC, just to the right of the accelerator peddle. You should see two vacuum actuators on that side, one near the accelerator peddle, and one up high. Blue goes to high one, yellow goes in the middle, red to lower connection.
 

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My door has a summertime feature...summertime it works, and summertime it don't....
 

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what a common problem . I've given up on mine several times. Also when the previous owner had changed the intake and carb. and never hooked the heater core back up to the intake and pump which doesn't bother me here in Texas but now that summer is coming again sure will be nice to have A/c blow thru vents again. Any shops in the dfw area anyone would reccommend for this service ? :texas:
 
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there is a flapper valve not opening, remove the center trim piece that holds the 2 middle air registers, reach into the hole and feel for the door inside, if you can't lift it, then it has glued itself in place. there is a duct leading to the door, it is held in with 2 screws, remove it for more room, Find the edge of the rubber seal on the door and work something between the seal and the airbox to free the door. Mine was very hard to do, but once freed up, it works great.
 

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Still fighting with the vents

I have been over this car 3 times...The A/C worked perfectly before I installed a dash cap...Now I have the all too familiar default defroster and floor air coming out....The temp control works fine...Blend door working as it should.All the tubes going to the switch are in tight...I removed the middle panel again to check the door or flap as some call it...It opens and closes manually...How does that door get opened???Simply by the air pushing it up???It seems like a fairly strong spring on it...I velcroed the door open,figuring that the air had to come out with the door held open...Air does come out but,the air is still coming out the defroster and floor vents...The air is very strong out the floor...I'm at the point where I'm thinking maybe the vacuum control switch needs to be replaced(where all the different color hoses attach)...Is there another way of directing the flow manually???The purple and gray and black hoses look right.The orange and yellow are hooked up right...I keep reading to check the ducting at the heater box(SOSA) and check the vacuum...I'm at a loss...Any help would be great...Any mechanics near Myrtle Beach????I'm more than willing to pay to get this fixed....Thanks for letting me VENT...No pun intended...
 
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the flapper is operated by vacuum, it is possible the vac motor is bad. Get a hand vacuum pump and connect it to each vac motor and test them,
 
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