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Headlights Vacuum backwards

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Old Jun 23, 2020 | 01:08 PM
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Default Headlights Vacuum backwards

I am getting into my 76 that had several POs...

In getting into the headlights which didnt work, I checked the vacuum lines, replaced the actuators....
Afterwards the pull down switch raised the lights, but the light switch did not...

I got access to the switch, and have a new one to install....After getting to it, I found the old switch had NO VACUUM PORTS.

In looking at vacuum diagrams, the dash switch seems be just wired series in with the pull down switch..

(Simple enough I thought)

When I turn the lights OFF, they raise, when I turn them ON, they close...
(OK, something is backwards.. Can only be 2 things right)
I switched lines on the pulldown and the switch itself...
No changes...

Lines are faded and I cant make out the stripe colors...

What the heck and I missing?

Should not be this hard... :/

Using this post as reference:
https://www.corvetteforum.com/forums...tem-works.html

Last edited by Gazpar; Jun 23, 2020 at 01:09 PM.
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Old Jun 23, 2020 | 01:42 PM
  #2  
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From: mount holly NC
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Default Hi and welcome!

Try testing the actuators as you may have the big hoses reversed.

The hoses on the switch connect like this:




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Old Jun 23, 2020 | 01:45 PM
  #3  
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Default Does this help?

http://corvette-101.com/
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Old Jun 23, 2020 | 02:29 PM
  #4  
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Default

Originally Posted by Peterbuilt
Try testing the actuators as you may have the big hoses reversed.

The hoses on the switch connect like this:

BINGO!

I knew it was something simple...

I feel like a dumb-a*s, but a dumba*s with working lights
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Old Jun 24, 2020 | 09:01 PM
  #5  
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Default

Just reverse the red & green vacuum lines on either the headlamp vacuum relays OR on the headlamp actuators (not both). The yellow-striped vacuum lines (vacuum feed) go to the center tap on the relays.

P.S. The green-striped vacuum lines are supposed to be at the bottom end of the relays (opposite the diaphragm).

Last edited by 7T1vette; Jun 24, 2020 at 09:03 PM.
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