Author Topic: Manual climate control right side levers 'sticky'  (Read 62 times)

Diesel 617

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Manual climate control right side levers 'sticky'
« on: 08 April 2019, 09:19 AM »
Thank you Casey your thread was a help: https://forum.w116.org/interiors-and-exteriors/manual-climate-control-operation/

Short version: Right side climate control levels, heater gets stuck when clicked into place and air flow goes down about 90%. Heater lever makes loud bang when getting unstuck. Tighten all bolts, and helped a little. No obvious obstructions. Any thoughts? Left side 100% operational.

Detailed:
The left side of my manual climate control levers operates without a hitch. The right side not so much. The air flow lever goes down about 90% of the way and refuses to go down the remaining 10%. There is an elastic like resistance, I can force it down but then it goes back to 90%. On the same side with the heater lever I can move it all the way up and down, however at the top when it 'clicks' into place it gets stuck and it requires moving the lever moderately fast downward to get it unstuck, accompanied by a loud bang as it gets unstuck. I opened up the passenger side, and I confirmed that it is the lower flap on the heater box that is getting stuck, upon closer inspection the lower flap refuses to close 100%, even when the heater level is 'clicked' into place. I would say about 90-95% closed. I believe the two symptoms are directly related. I have tighten all the nuts as they were loose, I can't see anything visibly hampering the movement, anyone have any ideas?
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tcj

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Re: Manual climate control right side levers 'sticky'
« Reply #1 on: 08 April 2019, 11:08 AM »
sounds like the big job: remove the heater box and replace the missing foam material on the flaps.
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Squiggle Dog

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Re: Manual climate control right side levers 'sticky'
« Reply #2 on: 08 April 2019, 01:14 PM »
sounds like the big job: remove the heater box and replace the missing foam material on the flaps.

Yes, I think that when the flaps on the inside of the heater box are missing foam, they jam into place because it throws off the geometry. I found the design of the manual climate control heater box interior flaps insane, so when I converted my car from automatic climate control to manual, I used the automatic climate control box and forwent the interior flaps, as they seemed overkill anyway--and this allowed the sliders to move with little effort. It also allowed me to retain the larger heater core that the automatic climate control cars had.
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1967 W110 Universal Wagon, Euro, Turbo Diesel, Tail Fins, 4 Speed Manual Column Shift, A/C
1980 W116 300SD Turbo Diesel, DB479 Walnut Brown, Sunroof, Heated Seats, 346,000+ Miles