Vacuum headlights???
Thread Starter
Pro
Joined: Aug 1999
Posts: 749
Likes: 0
From: Perth,Western Australia,Australia
Vacuum headlights???
Just done all the hose work on my car,so have never had the vacuum system working before.Is it normal for one headlight door to come up slower than the other,& go down slower than the other one.
I "wired" the hoses so that both were operated by one relay,but that just seemed to make matters worse.
Appreciate some input on this,Thanks Neil.
I "wired" the hoses so that both were operated by one relay,but that just seemed to make matters worse.
Appreciate some input on this,Thanks Neil.
Intermediate
Joined: Jul 2002
Posts: 46
Likes: 0
From: Stephens City VA
Re: Vacuum headlights??? (Fleetwood)
My '76 does this, especially when the car has not had a chance to warm up. Even when otally warm, the drivers side light is faster to open than the other.
If you find a solution, let me know and I will try it.
If you find a solution, let me know and I will try it.
Drifting
Joined: Jun 2001
Posts: 1,934
Likes: 5
From: Mount Vernon Arkansas
St. Jude Donor '12-'13
Re: Vacuum headlights??? (iveka)
quote-----------------------------------------------------------------------------------
"If you find a solution, let me know and I will try it."
-----------------------------------------------------------------------------------------
:withstupid: Me too!
[Modified by 1SGRET, 8:38 AM 12/29/2003]
"If you find a solution, let me know and I will try it."
-----------------------------------------------------------------------------------------
:withstupid: Me too!
[Modified by 1SGRET, 8:38 AM 12/29/2003]
Drifting
Joined: Nov 2003
Posts: 1,634
Likes: 4
From: Northern NJ
St. Jude Donor '04 & '05
Re: Vacuum headlights??? (Fleetwood)
I too have this same issue w/my 75. I haven't tried it yet but I read somewhere that if you keep both sets of vacuum hoses the same length, thus creating the same "volume" of space, that the two lights should come up at the same time. In theory this makes sense, but I dont know if it actually works. However I will be trying this in the spring when the car comes out of winter storage.
Of course this would work only if all other components are in good working order.
Hope this helps. Would appreciate any feedback on this if any of you try it.
:seeya
Of course this would work only if all other components are in good working order.
Hope this helps. Would appreciate any feedback on this if any of you try it.
:seeya
Melting Slicks
Joined: Feb 2002
Posts: 2,298
Likes: 1
From: Sodertalje/Sweden
Re: Vacuum headlights??? (iveka)
My '76 does this, especially when the car has not had a chance to warm up. Even when otally warm, the drivers side light is faster to open than the other.
If you find a solution, let me know and I will try it.
If you find a solution, let me know and I will try it.
This is kinda wierd..
Thread Starter
Pro
Joined: Aug 1999
Posts: 749
Likes: 0
From: Perth,Western Australia,Australia
Re: Vacuum headlights??? (ACECO)
Thanks for all the replies,I'll test the actuators & check out the difference in hose length as well,glad I'm not the only one with this problem. :yesnod:
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Team Owner
Joined: May 2001
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From: Exiled to Richmond, VA - Finally sold my house in Murfreesboro, TN ?? Corner of "Bumf*&k and 'You've got a purdy mouth'."
CI 6-7-8 Veteran
CI-VIII Burnout Champ
St. Jude Donor '06-'10, '13
Re: Vacuum headlights??? (jac1502)
Yep, my 1980 is the same way. Left then right.
Team Owner
Joined: Dec 2000
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From: Swords Check/Saws Check/Clubs Check/Claws Check/Hatred Check/Anger Check/Murmaid Check/Murder Check
Cruise-In IV Veteran
Cruise-In VI Veteran
Re: Vacuum headlights??? (BSeery)
Yep, my 1980 is the same way. Left then right.
Drifting
Joined: Dec 2002
Posts: 1,861
Likes: 2
From: New Zealand
Re: Vacuum headlights??? (Fleetwood)
........I don't think the hose length has anything to do with it......if there's a leak in the system, then it doesn't matter if the hose is 1" or 5 feet.......the amount of vacuum should be equal throughout the system......
I had the same problem with mine, replaced all the hoses, now it works like brand new........of course it wasn't an instant success......a pinched hose at the headlight switch when I replaced the dash made it a challenge until I routed the hose correctly.......initially, I had a bad signal hose (small white), which made the headlights open one after another and sluggishly......but in reality it could have been any part in the system.......
Instead of combining the two headlights, it would be better to isolate them and work with one headlight subsystem at a time.......you can also bypass the vacuum reservoir and deal with it separately........
just remember.......you should be pulling the same amount of vacuum through each component and hose in the system and you must check these methodically.......Hope this helps...... :cheers:
I had the same problem with mine, replaced all the hoses, now it works like brand new........of course it wasn't an instant success......a pinched hose at the headlight switch when I replaced the dash made it a challenge until I routed the hose correctly.......initially, I had a bad signal hose (small white), which made the headlights open one after another and sluggishly......but in reality it could have been any part in the system.......
Instead of combining the two headlights, it would be better to isolate them and work with one headlight subsystem at a time.......you can also bypass the vacuum reservoir and deal with it separately........
just remember.......you should be pulling the same amount of vacuum through each component and hose in the system and you must check these methodically.......Hope this helps...... :cheers:
Burning Brakes
Joined: Jul 2001
Posts: 853
Likes: 0
From: Foxfield, Co
Re: Vacuum headlights??? (Fleetwood)
Is it normal for one headlight door to come up slower than the other,& go down slower than the other one.
---------------------------------------------
I kind of like them moving at slightly different speeds, it really kind of catches some peoples attention to something else that makes these old corvettes different than todays newer always perfect no personality cars.
;)
---------------------------------------------
I kind of like them moving at slightly different speeds, it really kind of catches some peoples attention to something else that makes these old corvettes different than todays newer always perfect no personality cars.
;)
Melting Slicks
Joined: Feb 2001
Posts: 2,115
Likes: 0
From: VA
Re: Vacuum headlights??? (greg454)
Is it normal for one headlight door to come up slower than the other,& go down slower than the other one.
---------------------------------------------
I kind of like them moving at slightly different speeds, it really kind of catches some peoples attention to something else that makes these old corvettes different than todays newer always perfect no personality cars.
;)
---------------------------------------------
I kind of like them moving at slightly different speeds, it really kind of catches some peoples attention to something else that makes these old corvettes different than todays newer always perfect no personality cars.
;)
Ron
Drifting
Joined: Apr 2003
Posts: 1,323
Likes: 2
From: Castle Hills Texas
Re: Vacuum headlights??? (Fleetwood)
My '80 headlights pop up quick and at the same time. I do not believe the tube theory is correct. I would bet on actuators being tired. Of course I have not had any problems with mine yet but from all I have gleaned fom conversations from folks smarter than I, this is what I recall hearing.
Le Mans Master
Joined: Mar 2000
Posts: 9,127
Likes: 2,326
From: Pottsville, PA. USA Home Of America's Oldest Brewery Yuengling
Re: Vacuum headlights??? (CVT4ME)
There is a leak in the system. Check the seal in the canister if it is ok, then you have a leaky relay valve.
Instructor
Joined: Dec 2003
Posts: 167
Likes: 8
From: Blythewood S.C.
St. Jude Donor '14
Re: Vacuum headlights??? (Fleetwood)
I ended up changing the boots on both of the vacuam accuators and replacing one of the relays before mine worked ok on my '78. Another trick you might want to try is to enlarge the hole of the inlet fitting on the vacuam cannister,( the long cylindrical cannister underneath the headlights). This fitting is connected to the intake manifold and is located on the top side of the cannister close to underneath the drivers side light. A guy who has been working on Vettes for many years told me of this trick, I tried it and it did help but the boots were just too far gone so they had to be replaced. The rubber boots are only about 10 bucks each and well worth it. The lights still don't come up at exactly the same time every time but neither do some other things. :sad:
[Modified by MGB, 12:41 AM 12/30/2003]
[Modified by MGB, 12:41 AM 12/30/2003]
Thread Starter
Pro
Joined: Aug 1999
Posts: 749
Likes: 0
From: Perth,Western Australia,Australia
Re: Vacuum headlights??? (MGB)
I ended up changing the boots on both of the vacuam accuators and replacing one of the relays before mine worked ok on my '78. Another trick you might want to try is to enlarge the hole of the inlet fitting on the vacuam cannister,( the long cylindrical cannister underneath the headlights). This fitting is connected to the intake manifold and is located on the top side of the cannister close to underneath the drivers side light. A guy who has been working on Vettes for many years told me of this trick, I tried it and it did help but the boots were just too far gone so they had to be replaced. The rubber boots are only about 10 bucks each and well worth it. The lights still don't come up at exactly the same time every time but neither do some other things. :sad:
Can't see how making the inlet hole in the vacuum tank bigger would help in bringing up the light lids at the same time
Le Mans Master
Joined: Apr 1999
Posts: 6,134
Likes: 46
From: Raleigh North Carolina
Re: Vacuum headlights??? (Fleetwood)
The relays wear out internally... and there is a vacuum loss internally. This causes them to operate at different rates.
The best fix I have fouind is to disassemble the relays and cut a groove in the piston where an o-ring can be fitted. Re-assemble with a non-petroleum based grease and they work even and better than new.
New relays seldom have the same reaction time. Rebuilt o-ringed relays tend to operate faster and at a more constant rate.
The job is a little tricky because you have to cut the relay with a dremel to get it apart, and, you have to have a surgeons touch to avoid ruining the piston when you cut the groove in it. Not many people have the ambition/skill/patience to do this job, but when done correctly, it works great.
The best fix I have fouind is to disassemble the relays and cut a groove in the piston where an o-ring can be fitted. Re-assemble with a non-petroleum based grease and they work even and better than new.
New relays seldom have the same reaction time. Rebuilt o-ringed relays tend to operate faster and at a more constant rate.
The job is a little tricky because you have to cut the relay with a dremel to get it apart, and, you have to have a surgeons touch to avoid ruining the piston when you cut the groove in it. Not many people have the ambition/skill/patience to do this job, but when done correctly, it works great.
5th Gear
Joined: Dec 2003
Posts: 5
Likes: 0
From: ft. myers fl
Re: Vacuum headlights??? (Tom454)
I had the same problem on my 76. during inspection i found both actuator
seals were bad so i replaced them. This didnt help much except made the left a lot faster. I then swapped the hoses from the rt. relay to the lft. relay
and the problem folled to the drivers side. Replaced the pass. side relay and problem was solved. They dont exactly open at the same time but close.
My eyes in the morning are the same way one drags behind the other till i get my coffee.
seals were bad so i replaced them. This didnt help much except made the left a lot faster. I then swapped the hoses from the rt. relay to the lft. relay
and the problem folled to the drivers side. Replaced the pass. side relay and problem was solved. They dont exactly open at the same time but close.
My eyes in the morning are the same way one drags behind the other till i get my coffee.