69 Lazy Headlight Operation
Thread Starter
Drifting
Joined: Apr 2002
Posts: 1,720
Likes: 19
From: Manhattan Beach Ca
69 Lazy Headlight Operation
For 6 yrs my vacuum stuff has worked perfect. Lights, wiper door, heater vents etc..
Without touching anything now my driverside light takes 30-45 seconds to come up or down. Obviously it's a vacuum thing but what/where?
Hoping someone has had this exact issue. THX
Without touching anything now my driverside light takes 30-45 seconds to come up or down. Obviously it's a vacuum thing but what/where?
Hoping someone has had this exact issue. THX
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Does '69 have a single headlight relay or a pair? Mine have a pair.
If you have a single you can rule it out since the one side works properly. That leaves possibly binding moving parts, or a bad actuator.
If you have a single you can rule it out since the one side works properly. That leaves possibly binding moving parts, or a bad actuator.
Team Owner
Joined: Sep 2006
Posts: 31,200
Likes: 4,287
From: Westminster Maryland
Hi S69,
If you have a vacuum source you can connect the source hose directly to the front and then rear actuator nipple, while blocking the opposite nipple. The headlight should move 'smartly' up and down as you move the hose if the actuator is functioning properly. Vacuum on the front nipple moves the light up and on the rear nipple moves the light down.
It sounds to me like the leak is on the up side since there is vacuum to hold the light down but it takes time to build the vacuum to pull the light up. Good Luck!
Regards,
Alan
If you have a vacuum source you can connect the source hose directly to the front and then rear actuator nipple, while blocking the opposite nipple. The headlight should move 'smartly' up and down as you move the hose if the actuator is functioning properly. Vacuum on the front nipple moves the light up and on the rear nipple moves the light down.
It sounds to me like the leak is on the up side since there is vacuum to hold the light down but it takes time to build the vacuum to pull the light up. Good Luck!
Regards,
Alan
Le Mans Master
Joined: Aug 2006
Posts: 7,419
Likes: 1,555
From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
2019 C3 of Year Finalist (appearance mods)
Slow headlights
The most common problem is the seal in the actuator going bad,
www.riksvet.com part #HDL173.
Here's a link to a troubleshooting guide http://www.corvette-101.com/vacuum.htm the text is good but the diagram is not for your year and is wrong at the headlight and pull down connections. PG
www.riksvet.com part #HDL173.
Here's a link to a troubleshooting guide http://www.corvette-101.com/vacuum.htm the text is good but the diagram is not for your year and is wrong at the headlight and pull down connections. PG
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
I'm thinking Surfer has a hole in the actuator diaphragm.
Surfer with the engine running headlights on and both headlights in the up position-remove the red hose on the rear nipple of the drivers side actuator-now put your finger on the actuator nipple and feel for vacuum-if you feel vacuum building on your finger the diaphragm is bad.
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
