74 headlamp doors
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6th Gear
Joined: Mar 2006
Posts: 6
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74 headlamp doors
When I start my 74 the headlamp doors both raise for a moment then lower on there own. The vacuume check on the light switch checks out ok as does the manual switch and the check valve. Any ideas?
Safety Car
Joined: Jul 2002
Posts: 4,269
Likes: 3
From: St. Charles IL
Cruise-In 5-6-7-8-9-11-12 Veteran
A CI-6 Car Show Winner
Mine were doing the winkies when I shut it down. I would start with a hand held vacuum pump on the headlight actuator ports that face rear. Vacuum will close the doors from there and the actuators should hold vacuum. If they don't hold vacuum the diaphragm is shot and the actuator will need to be replaced. If that checks out, then do the same procedure on the ports facing the front of the car. Vacuum applied with your hand pump will open the dooors, and once fully opened they should hold vacuum. If they fail to hold vacuum you need to replace the seals. Less then 50 bucks to do both, and usually only a couple of hours work. The actuators can be removed from underneath with the valence panel, inner headlight braces, control valves, and possibly the horn removed. Hope this helps.
