vacuum headlight problems
Thread Starter
Melting Slicks
Joined: Dec 2003
Posts: 2,487
Likes: 1
From: Sydney
vacuum headlight problems
Hi everyone,
ok have just installed a new dewitts radiator and also hooker headers and side exhaust. The car is running (haven't done the timing as I need to get a timing light). anyway, I was eager to take the car around the block last night...the headlights wouldn't pop up. They did work before (sort of), one headlight popped up, and one needed a little assistance. Anyway, now neither of them would go up, so I manually pushed them up.
They will not come back down! the manual override is off.
I don't know why I suddenly have this vaccum problem. I haven't disconnected anything.
I did a search and found a post that said:
"Your headlight parts may need some oil but they should not be stuck closed, you can reach under your Vette and move them up and down a little. Don't push them up to far or they will stay up! Just move them a little to prove that they do move."
So, relating to the comment posted above, have I done something bad by pushing them up by hand? Why would they 'stay up'? and not come back down.
ok have just installed a new dewitts radiator and also hooker headers and side exhaust. The car is running (haven't done the timing as I need to get a timing light). anyway, I was eager to take the car around the block last night...the headlights wouldn't pop up. They did work before (sort of), one headlight popped up, and one needed a little assistance. Anyway, now neither of them would go up, so I manually pushed them up.
They will not come back down! the manual override is off.
I don't know why I suddenly have this vaccum problem. I haven't disconnected anything.
I did a search and found a post that said:
"Your headlight parts may need some oil but they should not be stuck closed, you can reach under your Vette and move them up and down a little. Don't push them up to far or they will stay up! Just move them a little to prove that they do move."
So, relating to the comment posted above, have I done something bad by pushing them up by hand? Why would they 'stay up'? and not come back down.
Drifting
Joined: Jul 2008
Posts: 1,873
Likes: 27
From: Sonora CA
Even if you push them all the way up, you can still pull them down, BUT ONLY if you reach under and pull on the mechanism that opens them. Never try to push them down by pushing on the headlights themselves. There are springs on the mechanism that keep the lights up by default. Look at the mechanism, study it, understand how it works. This system is not rocket science and IMO is easy to trouble-shoot. A propertly maintained system will still work even with low vaccum
Instructor
Joined: Apr 2004
Posts: 201
Likes: 1
From: Taunton Ma
You will not hurt your headlights by opening and closing them by reaching under the car and tugging on the mechnisum in the correct place. As imariver suggest take a look and you will see how it works. BUt you have a vaccum problem. You had one before you installed the radiator and by replaceing it you probably moved some vaccum line around and either knocked one off or they are so old that they need replacing. The best thing that i did when i first got my car with headlight issues was purchase a vaccum hose kit. This way you have a baseline and you know your hoses are good after that i had to replace one relay and it has been fine ever since.
Intermediate
Joined: Feb 2009
Posts: 48
Likes: 0
Un plug your hoses at the headlight and with a short
length of tubing connected to the rear of canister ( down side) see if you can suck the light down.
Then try the front side (up) . If the linkage can be moved by hand and not rusty you need a seal kit.
All the corvette suppliers have them for about $30.00 .
(for both sides)
Just make sure you get the "retainer ring" too.
Some kits have just the seals.
length of tubing connected to the rear of canister ( down side) see if you can suck the light down.
Then try the front side (up) . If the linkage can be moved by hand and not rusty you need a seal kit.
All the corvette suppliers have them for about $30.00 .
(for both sides)
Just make sure you get the "retainer ring" too.
Some kits have just the seals.
Racer
Joined: Mar 2006
Posts: 366
Likes: 1
From: Houston Texas
Check that you have vacuum at the relay for both the control signal and the main lines. If not, work backwards to the connection you use for the vacuum source.
Team Owner
Joined: Sep 2006
Posts: 31,301
Likes: 4,389
From: Westminster Maryland
Hi CV,
There's an 'knee' shaped part of the linkage that needs to be pulled down to release the headlight mechanism. It locks the headlight in the up position. The vacuum actuator has enough power to overcome the 'lock', but YOU need to pull it to get the headlight to go down by pushing it by hand.
Perhaps you might want to think about getting the GM CHASSIS SERVICE MANUAL for your car, it'll help you with little jobs like this. Wilcox has a lot of vacuum trouble shooting help on this site too, if you search.
Regards,
Alan
There's an 'knee' shaped part of the linkage that needs to be pulled down to release the headlight mechanism. It locks the headlight in the up position. The vacuum actuator has enough power to overcome the 'lock', but YOU need to pull it to get the headlight to go down by pushing it by hand.
Perhaps you might want to think about getting the GM CHASSIS SERVICE MANUAL for your car, it'll help you with little jobs like this. Wilcox has a lot of vacuum trouble shooting help on this site too, if you search.
Regards,
Alan
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Every 2027 Corvette Engine Explained
Joe Kucinski
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette
Verdad Gallardo
10 Ugly Corvettes That We Still Kinda Love
Joe Kucinski
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
