Headlamp door not operating properly - RS 1969

[lemarin]

I had my car restored last winter. All the piping/valves are new for the headlamp door operation. I recently bought an NOS switch no 1995191. Now when the switch is pull out completely, headlamps+Fog lamps switch on, but the doors close, when I push the switch to OFF position, then the headlamp door opens.

What can be wrong ? I tried to exchange both vacuum pipes behind the headlamp switch, it doesn't work, then I tried to exchange both red and green vacuum pipe on the relay/valve under the hood and it doesn't work either.

Any idea ?

[rich69rs]

Got to be something with the vacuum routing to the relay valve and down to the canisters that open the doors.

A few years ago, when I had the front of the car disassembled, I changed out the original canisters (kept the originals and put them away) for new aftermarket.  The new canisters operated backward from the originals.  I had to swap the vacuum hoses at the canisters to make everything work properly.

[lemarin]

I understand that the new canister were built differently, I'm just trying to figure what's the difference between swapping the hoses directly at both canister, or swapping the hoses like I did, at the output of the relay valve ?

[Mark]

There are some wrong installation diagrams out there, including possibly the AIM.  The valve on your vacuum tank should have the red line on the top connection, yellow hose to the vacuum tank on the middle connector, green hose to the back of the actuators on the bottom connector.  Under the dash the hose from the engine (orange striped one) on the barb closest to the firewall, and the other one to the top of the actuator valve next to the vacuum tank on the one closest to the dash.  When you pull the headlight switch out vacuum is supplied to the top of the actuator valve which pulls the valve slider up, which connects the center port to the red hose which pulls the piston in the actuator forward opening up the headlight doors.  When the headlight switch is pushed forward the vacuum is cut off and vented from the actuator valve, and the spool returns to its normal position with vacuum connected to the green lines at the back of the actuator which pull the headlight doors closed.  Should work the same way if you put the manual slide on the actuator valve in the open position.  Doors should open with that lever pulled out, and closed with it pushed back in.

Colors of hoses attached to the valve in this post are backwards, Green goes on top, Red goes on the bottom - leaving original text in place since it is clarified in a post below.

[lemarin]

You resume exactly what I have under my hood. There's only behind the canister that I can't access and see if its properly connected.

I used this diagram to check my system, and it's exactly the way it is routed/connected

[lemarin]

But Mark, can you confirm that on the Vacuum relay valve, if you swap the red line and connect it at the bottom, and connect the green line to the top keeping the yellow line at the center, then when you pull the switch to ON, the covers should be close, and act opposite of what it should be ? Right ?

[Mark]

If the hoses between the valve and the actuators are swapped (at either end) then the system will operate backwards, the doors should close when you pull the manual override out, and open with it pushed in.  Same with the headlight switch, head lights off, doors will open, headlights on doors will close.

[camaroboy68ss]

I agree with the others, swap the lines on the valve first, I installed a new valve last summer and found that that it worked backwards of the one I replaced, had the same issue you had, with the switch pushed in to off the doors opened and when I pulled on the headlights they close.

[Mark]

This was a post of mine from 2008 over at Camaros.net when I replaced my original actuator with a repro one and I had the same backwards operation issue.

"The repro headlight relays are labeled backwards. The green hose goes on the top connection and to the back of the actuators, the red hose goes on the bottom and connects to the front of the actuators. With the car running and the headlight switch off vacuum is connected to the top of the headlight relay which pulls up on the diaphragm moving the relay shuttle up and connecting vacuum to the green hoses (back of actuator) which pulls the actuator rods back into the actuator can and pulls the doors closed. When you pull the headlight switch out vacuum is cutoff and vented from the top of the headlight relay and the shuttle moves down (by spring pressure) to connect the red hoses to the front of the actuator which extends the actuator rods and opens the headlight doors.

When you put the override switch into the open position you are plugging up the vacuum connection to the relay which allows the relay shuttle to get pushed down connecting the center vacuum port to the red hoses which opens the headlight doors. If the valve is off the car you can check it by blowing thru the center port, air should come out the bottom port. Apply vacuum to the top of the actuator and air should come out the top port. Make sure the shuttle moves in the relay valve. Push upon the bottom of the shuttle with a 1/4" drive extension, or small dowel. It should move up about 1/4" to 3/8" and then spring back down when you release it. Old ones have a tendency to collect grit and grease and jam up as they draw air up thru the bottom. Clean out to inside with some brake or carb cleaner, and then lube it with some silicone, or dry graphite lube.

My post (Reply#3) above is wrong, the green hose goes on the top, red on the bottom (assuming the green is on the back of the can, and red is on the front) and Yellow in the middle.  I believe the repro actuator valve bodies are (or were) the same ones used for the C3 corvettes and they are labeled opposite the ones used in the Camaro.  They have the R on top, Y on the middle and G on the bottom.  So if you have a repro actuator, the letters on the valve itself are backwards.

[lemarin]

It works great now ! I was not enough patient to have the pressure to built in, so I taught it was not working. Just swap the green and red hoses on the relay valve, and it works the way it should be.

Thanks to all, sometime the owner's skill is the problem !