I made an automatic pop door for my coop using the Add-a-Motor D-20 as the engine to lift the door. It worked great for about seven months.
(Construction image)
![](https://www.backyardchickens.com/content/type/61/id/5389901/width/350/height/700)
(Switch that turns the porch light on when closed and off when the door is open)
![](https://www.backyardchickens.com/content/type/61/id/5389902/width/350/height/700)
(Construction image)
![](https://www.backyardchickens.com/content/type/61/id/5389904/width/350/height/700)
(Finished)
![](https://www.backyardchickens.com/content/type/61/id/5389905/width/350/height/700)
Yesterday morning I noticed the porch light I set up on the coop was still on at 8:00 am.. that means the pop door was still closed; very strange.
I tripped the manual switch on the timer & the motor just continued to run.. that meant the "on/off" switch in the motor wasn't being activated..
So after reading the warranty, shaking my head & laughing to myself. I opened the unit & noticed the gear that is used to operate the "fingers" that trip the "on/off" switch that stops the motor and reel from spinning was bouncing around loose in the case. I noticed right away that the plastic post that held the aforementioned gear in place snapped off .. I still haven't determined the cause though.
After digging through my tool box I found a steel 3/32 ejector pin from my machinists days that was very close in diameter to the plastic post that had snapped off.
I just drilled a blind press fit hole where the broken plastic post had been. Cut the pin to length and using some JB Weld I set the new steel pin in place.
Reassembly was straight forward. The D-20 is operating as well as before.
The tip of the screw pointing to where the plastic post was.
![](https://www.backyardchickens.com/content/type/61/id/5389892/width/350/height/700)
The gear and broken plastic post.
![](https://www.backyardchickens.com/content/type/61/id/5389893/width/350/height/700)
The 3/32 ejector pin and after I drilled the blind hole for the pin.
![](https://www.backyardchickens.com/content/type/61/id/5389894/width/350/height/700)
The short piece of ejector pin epoxied in place with JB-Weld
![](https://www.backyardchickens.com/content/type/61/id/5389895/width/350/height/700)
I hope this helps should anyone else encounter problems with their D-20 motor.
(Construction image)
(Switch that turns the porch light on when closed and off when the door is open)
(Construction image)
(Finished)
Yesterday morning I noticed the porch light I set up on the coop was still on at 8:00 am.. that means the pop door was still closed; very strange.
I tripped the manual switch on the timer & the motor just continued to run.. that meant the "on/off" switch in the motor wasn't being activated..
So after reading the warranty, shaking my head & laughing to myself. I opened the unit & noticed the gear that is used to operate the "fingers" that trip the "on/off" switch that stops the motor and reel from spinning was bouncing around loose in the case. I noticed right away that the plastic post that held the aforementioned gear in place snapped off .. I still haven't determined the cause though.
After digging through my tool box I found a steel 3/32 ejector pin from my machinists days that was very close in diameter to the plastic post that had snapped off.
I just drilled a blind press fit hole where the broken plastic post had been. Cut the pin to length and using some JB Weld I set the new steel pin in place.
Reassembly was straight forward. The D-20 is operating as well as before.
The tip of the screw pointing to where the plastic post was.
The gear and broken plastic post.
The 3/32 ejector pin and after I drilled the blind hole for the pin.
The short piece of ejector pin epoxied in place with JB-Weld
I hope this helps should anyone else encounter problems with their D-20 motor.