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headlights won't go down - HELP!

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Old Feb 11, 2012 | 08:19 PM
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Default headlights won't go down - HELP!

The previous owner replaced all the components for the headlight vacuum system on the '69 . I have downloaded the information manual and have been looking at all the routing of the rubber hoses and everything seems to checks out.

When I pull on the switch, the lights will go up and light up. However when I push the switch back in - nothing will happen. I've even replaced the switch itself thinking that was the problem - not so much.

The only way I can get the lights to close is unplug a hose from the switch or pull down on the manual override valve.

Any help would be greatly appreciated - as I can't put my dash together until this problem is fixed.

Thanks.
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Old Feb 11, 2012 | 10:09 PM
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usually it is one light instead of two. I'm guessing both relays are bad sounds strange both would go bad but i had 2 go bad at once so anything is possible. someone will chime in I'm sure
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Old Feb 11, 2012 | 10:12 PM
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My '69 came with one relay only.
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Old Feb 12, 2012 | 12:47 AM
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Originally Posted by KevinG
The only way I can get the lights to close is unplug a hose from the switch or pull down on the manual override valve.
That's really weird, pulling down on the manual override switch should make the headlights go up, not down. Sounds like the hoses are not hooked up right going to the relay.
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Old Feb 12, 2012 | 10:11 AM
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You may have the hose's reversed on the headlamp switch depending on which schematic you used. There are some floating around that are wrong.

The vacuum system is designed to come open if something fails... So lack of vacuum to the top of the small relay makes it open.

So use the schematic below and follow the vacuum. With the light switch and over-ride off you should have vacuum on black with white stripe hose going to the relay.

If you only get vacuum there when you pull the over-ride then you may have the hoses switched somewhere.... So go to the over-ride and see if the blue stripped hose has vacuum when the lamps are off and that it is closest to the **** end of the switch.

If it doesn't have vacuum with the lamps off and is closest to the **** end, then go to the headlamp switch and verify you have the blue stripe hose on the correct nipple. The vacuum supply hose always goes to the nipple closest to you when installing and it is very common to get this connection backwards.


Willcox



Last edited by Willcox Corvette; Feb 12, 2012 at 10:16 AM.
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Old Feb 12, 2012 | 11:01 AM
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Originally Posted by KevinG
My '69 came with one relay only.
You're okay. 68s and 69s have only one relay and have tees in the hoses. Later cars use two relays and no tees.

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Old Feb 12, 2012 | 11:13 AM
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Default I had the same problem

Originally Posted by Willcox Corvette
You may have the hose's reversed on the headlamp switch depending on which schematic you used. There are some floating around that are wrong.

The vacuum system is designed to come open if something fails... So lack of vacuum to the top of the small relay makes it open.

So use the schematic below and follow the vacuum. With the light switch and over-ride off you should have vacuum on black with white stripe hose going to the relay.

If you only get vacuum there when you pull the over-ride then you may have the hoses switched somewhere.... So go to the over-ride and see if the blue stripped hose has vacuum when the lamps are off and that it is closest to the **** end of the switch.

If it doesn't have vacuum with the lamps off and is closest to the **** end, then go to the headlamp switch and verify you have the blue stripe hose on the correct nipple. The vacuum supply hose always goes to the nipple closest to you when installing and it is very common to get this connection backwards.


Willcox


The vacuum lines/switch were installed following the blue GM build book...the headlight switch hoses are incorrect in the book, I made the switch, problem solved.
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Old Feb 12, 2012 | 11:41 AM
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Originally Posted by rbat
The vacuum lines/switch were installed following the blue GM build book...the headlight switch hoses are incorrect in the book, I made the switch, problem solved.
Yep... and for some crazy reason the hoses show backwards in there. The diagram above is correct and I'm hoping will solve his problem.
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Old Feb 12, 2012 | 01:40 PM
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Default how to switch

Just in case you have not done this before... remove the side screws in the door jam, two of the three under the dash (over the steering column and towards the door, pry it open a bit and wedge one of those 3.5" flashlights to hold it open and to provide light...use needle nose to switch the hoses, test and close her back up.

All of this is assuming you check all the other hoses to be connected correctly.

hope this helps.
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Old Feb 13, 2012 | 07:15 AM
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Originally Posted by rbat
Just in case you have not done this before... remove the side screws in the door jam, two of the three under the dash (over the steering column and towards the door, pry it open a bit and wedge one of those 3.5" flashlights to hold it open and to provide light...use needle nose to switch the hoses, test and close her back up.

All of this is assuming you check all the other hoses to be connected correctly.

hope this helps.
Thanks,
But the dash is all apart at the moment. We have not put any dash together until we figure out this headlight issue.

I will take a look at Wilcox's diagram and see if the tubes are routed correctly on the relay
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