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C3 headlight mech question

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Old Mar 28, 2021 | 11:56 AM
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Default C3 headlight mech question

Driver Headlight (1969) will not ‘lock’ open. Over the winter I had the actuators off and rebuilt them ... they passed the ‘plug the hole’ test and appear to be working fine. All new vacuum lines and components so I think it’s mechanical. In AIM I see the three bolts above actuator arm as an option to adjust if they won’t lock, that’s next, but they stayed open just fine before the actuators were removed? Before I get any deeper, do you guys see anything?? In the first picture you can see where the locking mechanism sits when held open, which isn’t engaging in locking position. Photo 2 I removed the tension springs and you see where it shifted correctly into locking position

Headlight being held in ‘up’ position, but not engaging in lock position and will fall right back down.

Removed the tension springs, allowing mechanism to engage in ‘lock ‘
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Old Mar 28, 2021 | 12:06 PM
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Originally Posted by Bremquest
Driver Headlight (1969) will not ‘lock’ open. Over the winter I had the actuators off and rebuilt them ... they passed the ‘plug the hole’ test and appear to be working fine. All new vacuum lines and components so I think it’s mechanical. In AIM I see the three bolts above actuator arm as an option to adjust if they won’t lock, that’s next, but they stayed open just fine before the actuators were removed? Before I get any deeper, do you guys see anything?? In the first picture you can see where the locking mechanism sits when held open, which isn’t engaging in locking position. Photo 2 I removed the tension springs and you see where it shifted correctly into locking position

Headlight being held in ‘up’ position, but not engaging in lock position and will fall right back down.

Removed the tension springs, allowing mechanism to engage in ‘lock ‘
Off the top of my head, if you turn the clevis a few turns more onto the shaft of the actuator, that will effectively shorten the 'throw' of the actuator shaft, and maybe allow it to pull the assembly open to the lock position. Of course, if that clevis wasn't removed and reinstalled as part of the repair, then it's still in it's original position and can't be the cause.
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Old Mar 28, 2021 | 12:14 PM
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Originally Posted by Catfish4818
Off the top of my head, if you turn the clevis a few turns more onto the shaft of the actuator, that will effectively shorten the 'throw' of the actuator shaft, and maybe allow it to pull the assembly open to the lock position. Of course, if that clevis wasn't removed and reinstalled as part of the repair, then it's still in it's original position and can't be the cause.
Nope I did remove it, so I must have spun it on too many turns
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Old Mar 28, 2021 | 12:14 PM
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2019 C3 of Year Finalist (appearance mods)
Default See the actuator NOTE>


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Old Mar 28, 2021 | 12:19 PM
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When you open the headlight and watch the mechanism, you can see it go past center. That is how it locks open.
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Old Mar 28, 2021 | 12:40 PM
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Originally Posted by kodpkd
When you open the headlight and watch the mechanism, you can see it go past center. That is how it locks open.
Right now when I open it up by hand it does not go past center, which is why it falls back down, if I forcefully push the mechanism past center it will lock but wants to close fairly easily. I am hoping I just spun the clevis on too many times. I will spit it back a few times and check again.
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Old Mar 28, 2021 | 02:18 PM
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Originally Posted by Peterbuilt
so it’s not turned on there much at all
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Old Mar 28, 2021 | 10:11 PM
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