JunkdriverToo

I need help for a 1973! Both headlights popped up and stayed up after starting the car. I have all the diagrams and will be working on it soon. I have read a warning not to put them down manually. Is there a way to put them down with a bypass of any kind? I am not sure if they stay up no matter what the problem, for safety reasons. Does the Override Switch only pull them up? Thanks I'm new at this.

Eddie 70

The override switch will open and close the headlights. Start the car and see if the override switch will close the headlights too. Down should cause the lights to go up and pushing the **** up should pull the lights down.

If you need to let the lights down manually, you can do it, just be careful because you can get your finger caught in the mechanism easily and possibly lose a finger. Just push on the back of the knee in the mechanism and the light should come down. Go easy when doing this and do not force the light down. You can wind up tearing the "witches hat" seal in the headlight.

Alan 71

Hi,
I believe putting the lights down manually is hard on the diaphragm in the actuators. Disconnecting the hoses from the actuators allows the vacuum to bleed off with out putting undo pressure on the diaphragms.
There is a point of pressure in the linkage that must also be over come when you begin to pull the lights closed.
Regards,
Alan

This is the 'elbow' ( lower center in the picture, silver part) you want to pull down on. DON"T pull on the plastic electrical switch... it's easy to break.



Hi Eddie, You beat me to it., I'm a slow typist.

Eddie 70

Beautiful headlight mechanism Alan. That is a work of art for sure.

JunkdriverToo

Thank you both!

JunkdriverToo

A couple more questions before I get started. Because my son (just back from Iraq) said: He cranked the starter and then the lights popped up. Is there anything electrical that could be the problem? What is the location and function of the Vacuum Relay? We only have 2 days together here in GA., so thank you in advance for your help! Also Eddie & Al Thank You!

Mike Ward

Here's a sticky that explains all:

http://forums.corvetteforum.com/c3-t...tem-works.html

Eddie 70

There is nothing electrical that will cause the headlights to come up. When cranking he probably built up enough vacuum to pull the headlights up. Could be that the over ride switch is pulled down. If the switch is pushed up and the lights still pop up you may have a vacuum line crossed somewhere.

jdp6000

Do you hear any hissing? Sounds like a vaccum leak. You basically have a feed off the back of the engine...disconnect the hose there. You should be getting suction. From there the hose runs into the car through the headlight switch and by pass. Headlight switch is hard to reach. But if you disconnect the hoses from the by pass you should feel suction. If you hear a hiss from the headlight switch the hose is leaking there. If all is good inside follow the hose that goes to the front of the car. There is a can mounted between the headlights...at least I think there is in your year and make. Suction build pressure in this can. From there it goes to the distribution valve and from there to each head light. If you disconnect the hose at each headlight actuator you should have suction from the hose. Check this route for suction at each stage. Then entire system works on suction.

You can't screw anything up by disconnecting hoses at each stage.

Jim