Can i please get some headlight help?
Thread Starter
Burning Brakes
Joined: Oct 2013
Posts: 992
Likes: 28
From: Sutton MA
Can i please get some headlight help?
When we first bought this car, the headlight switch was completely bypassed and I was told that the switch under the steering column was how you put them up and then used the headlight switch to turn them on. I'm trying to right the wrong so I rerouted the hoses correctly but after getting the new engine in I found out the headlight switch would not lift the lights up only turn them on. So we ran the car mostly during the day for the first week, occasionally using the headlights a couple times. Those couple times, we just used the bypass to lift them, and the switch to turn them on.
Then as time went on one night we suddenly lost the headlights, not the light but they suddenly went down. If I pushed the switch in, they would come back up, pulled the switch back out, they would drop, not immediately but shortly after. At that time I could hear a vacuum leak sound at the switch when it was pulled on, the sound would stop when it was off.
So I bought a new switch, changed it out and still have the same issues. The only way to get the lights to open is the bypass, as soon as the light switch is pulled they close immediately. I've checked and rechecked the hoses and they all seem to be connected properly. Any help would be appreciated.
Then as time went on one night we suddenly lost the headlights, not the light but they suddenly went down. If I pushed the switch in, they would come back up, pulled the switch back out, they would drop, not immediately but shortly after. At that time I could hear a vacuum leak sound at the switch when it was pulled on, the sound would stop when it was off.
So I bought a new switch, changed it out and still have the same issues. The only way to get the lights to open is the bypass, as soon as the light switch is pulled they close immediately. I've checked and rechecked the hoses and they all seem to be connected properly. Any help would be appreciated.
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,754
From: Charlotte NC
All I can write is that IF the hoses are correct...the system should work. I do it numerous times in a year. The two hoses that connect to your headlight switch need to be installed correctly.
I also verify that the vacuum switch that is made onto the headlight switch is working before I put it in. I ASSUME NOTHING.
This is also assuming that the actuator relays are good and the aluminum check valve off the intake vacuum is in good condition...so vacuum can be stored as designed.
DUB
Thread Starter
Burning Brakes
Joined: Oct 2013
Posts: 992
Likes: 28
From: Sutton MA
Dub I say seem because it's still not working correctly. According to diagrams the hoses are connected correctly. I guess I'll have to start testing each piece separately , I did find a good article on trouble shooting, i guess it's not as easy as I hoped it would be. Now I know why they bypassed the light switch.
8th Gear
Joined: Sep 2014
Posts: 8
Likes: 0
I have learned that in order to make lights go up you block vacuum to the control valves. According to the paper I received with my new hoses the vacuum supply goes to the back port of the headlight then from front port to the override switch. It does not take much of a leak to give you fits. I also bought a vacuum pump to test the actuators. Hope this helps.
Melting Slicks
Joined: Mar 2009
Posts: 3,126
Likes: 15
Safety Car
Joined: Dec 2007
Posts: 4,229
Likes: 39
From: Beautiful East Texas
Reverse the hoses on the headlight switch... the assembly manual (at least the one I have) shows the hoses reversed from what they really should be.
Went through the same thing on my '73.
mardyn
Went through the same thing on my '73.
mardyn
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Burning Brakes
Joined: Apr 2012
Posts: 1,084
Likes: 96
From: Bowmanville Ontario
I just saw a show on tv about this. They said that the NEW engine did NOT produce enough vacuum to raise the headlights. Maybe this is your problem.
You might need to install an electrical light system that I have seen people post on this forum.
Hope this helps.
Ken
You might need to install an electrical light system that I have seen people post on this forum.
Hope this helps.
Ken
Instructor
Joined: Nov 2013
Posts: 220
Likes: 17
From: Pasadena MD
When we first bought this car, the headlight switch was completely bypassed and I was told that the switch under the steering column was how you put them up and then used the headlight switch to turn them on. I'm trying to right the wrong so I rerouted the hoses correctly but after getting the new engine in I found out the headlight switch would not lift the lights up only turn them on. So we ran the car mostly during the day for the first week, occasionally using the headlights a couple times. Those couple times, we just used the bypass to lift them, and the switch to turn them on.
Then as time went on one night we suddenly lost the headlights, not the light but they suddenly went down. If I pushed the switch in, they would come back up, pulled the switch back out, they would drop, not immediately but shortly after. At that time I could hear a vacuum leak sound at the switch when it was pulled on, the sound would stop when it was off.
So I bought a new switch, changed it out and still have the same issues. The only way to get the lights to open is the bypass, as soon as the light switch is pulled they close immediately. I've checked and rechecked the hoses and they all seem to be connected properly. Any help would be appreciated.
Then as time went on one night we suddenly lost the headlights, not the light but they suddenly went down. If I pushed the switch in, they would come back up, pulled the switch back out, they would drop, not immediately but shortly after. At that time I could hear a vacuum leak sound at the switch when it was pulled on, the sound would stop when it was off.
So I bought a new switch, changed it out and still have the same issues. The only way to get the lights to open is the bypass, as soon as the light switch is pulled they close immediately. I've checked and rechecked the hoses and they all seem to be connected properly. Any help would be appreciated.
Melting Slicks
Joined: Jan 2014
Posts: 2,478
Likes: 254
From: Downers Grove Illinois
When I had my dash out recently the lights worked find before I pulled everything apart in my '77. When I put it all back together I had the same symptoms you are describing and it was due to having the vacuum hoses switched on the headlight switch. If that is not it I believe it is the vacuum portion of the headlight switch is defective.
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,754
From: Charlotte NC
Tooonz,
Your vacuum hoses are not correct. That is what I am betting on.
When you pull DOWN on the override switch...the door open...push it back UP and they close.
IF you removed your headlight switch (for example) and joined the 2 hoses together....you would only be able to use your OVERRIDE switch to raise and lower for headlights.
The ONE thing that you have to remember.... and it is simple.... is that the SMALL hoses that goes to your headlight actuator relays is the CONTROL for raising and lowering your doors. The control of the vacuum is done by the headlight switch or override switch.
When VACUUM is added and taken away on this small hose...it moves a plunger in the relay...which directs the vacuum to the corresponding hose that goes to your actuator pods.
SO...I am betting that you have a vacuum hose routing problem..or a bad headlight vacuum switch.
Check EVERY hose...and ESPECIALLY those at the headlights.
DUB
Your vacuum hoses are not correct. That is what I am betting on.
When you pull DOWN on the override switch...the door open...push it back UP and they close.
IF you removed your headlight switch (for example) and joined the 2 hoses together....you would only be able to use your OVERRIDE switch to raise and lower for headlights.
The ONE thing that you have to remember.... and it is simple.... is that the SMALL hoses that goes to your headlight actuator relays is the CONTROL for raising and lowering your doors. The control of the vacuum is done by the headlight switch or override switch.
When VACUUM is added and taken away on this small hose...it moves a plunger in the relay...which directs the vacuum to the corresponding hose that goes to your actuator pods.
SO...I am betting that you have a vacuum hose routing problem..or a bad headlight vacuum switch.
Check EVERY hose...and ESPECIALLY those at the headlights.
DUB
Thread Starter
Burning Brakes
Joined: Oct 2013
Posts: 992
Likes: 28
From: Sutton MA
I tested the headlight switch last night, because I had just purchased it. It tested fine, The bypass switch tested fine. I tested the check valve and it won't hold vacuum steady, so I will order a new one, but I agree I think something is crossed somewhere. According to what I've read, if the check valve is bad headlights stay up, and ours don't. The check valve is just ever so slightly leaking, it will get replaced but my gut tells me that isn't the monster I'm chasing right now.thanks for all the help so far, it's helping me understand our corvette a little better.
Thread Starter
Burning Brakes
Joined: Oct 2013
Posts: 992
Likes: 28
From: Sutton MA
I reassembled the inside hoses this morning as I wanted to drive it to work, I left the bypass switch pushed up, started the car and the lights opened. pulled the light switch and they closed so no progress yet ( sigh ) I have the white striped hose connected to the white port on the bypass switch, that is connected to the relays. the line from the small port on the check valve is connected to port two on the headlight switch, and the blue port on the bypass is connected to port three. this is all according to a diagram I printed from the Willcox website. Will an iffy check valve be causing this?
Drifting
Joined: Jul 2006
Posts: 1,259
Likes: 154
From: Deplorableville Nebraska
Your headlights are reacting exactly opposite of how they should be. The only component that switches vacuum between the up and down cycle is the headlight relays. If the actuating hoses are reversed, the up and down cycle is reversed also. Double check the hose connections at the relays. Do not pay any attention to the hose color. Simply make sure the bottom hose on the relay is connected to the front of the actuator, and the top hose is connected to the rear of the actuator.