AC/Heat Control Issues - Figured it out...

[bamachem]

I have an AC truck and was having trouble with the AC/Heater controls. They were very stiff and couldn't get two of them to move much at all. I thought it was the cables. I lubed them up and still no luck. I decided last night to pull my Damper/Coil Boxes to check everything out. Found a couple surprises. I'll let the pics do the talking!

Pretty obvious why this damper won't move... Needless to say, at some point this truck sat for a long, long time somewhere here in the south.



Interesting damper repair by a PO





Another Dirt Dobber Nest preventing a damper from actuating...



On top of all that, someone had at some point to add some extra screws to hold the plastic S-box to the other boxes due to cracking. The screws were protruding into the duct, preventing the repaired damper from being able to actuate more than an inch or so.

Luckily, my truck came with a spare set of AC/Heat boxes so I was able to compare originals to spares and put the best of the bunch back in the truck.

Only problem is that I'm missing the Control Head Vacuum Switch completely. I can't locate it at all. Any help on where to find it would be appreciated, but I think it may be missing.



One more I almost forgot about. I checked all the vacuum actuators. The heater coolant control valve works great. The Recirculated Air Door works OK, but the old stiff gasket causes it to stick and not open all that well. The vacuum actuator for the Outside Air Door works, but the outside air door will not move. I didn't have time to remove the cowl, but I'm suspecting another dobber next and I'm hoping it's not something mechanical or cancer/rust. I'm saving that for another day.