After my last repairs at the car, the right headlight door did no longer close properly. Only if I wiggled on the vacuum hose on the actuator which is responsible for opening the door (the green hose), the door would eventually close. So I thought that the actuator was shot and I ordered one from a 1969 Camaro RS which looks almost identical with the only difference being the rod ends which are completely different on the Camaro. The original mounting pins on the Eldorado are screwed on and can be removed pretty easily from the rod, which has a thread on the end. On the Camaro actuators, the rod end is pressed in place and the rod has no thread at all... So one would have to find a way to switch the rod ends and modify the reproduction actuators...

The instructions on the reproduction part mentioned that one could use silicone spray to lube the internals of the actuator through the vacuum inlets - this would also make the rubber parts in there soft for a better sealing. So I thought it might be a good idea to spray something in my old part and really soak it...
I had the impression that the rod was easier to move after application. I also put some gasket sealant around the vacuum inlets, just to make sure that there is no leak anywhere.
So I installed the old unit once again and it still did not work properly - but it worked fine if I only installed one vacuum line at a time. Suddenly it rang a bell. There are some T-connectors which also act as a valve going to each actuator. They do vent the system on one side when the doors are operated.
I cleaned the connector valve and reinstalled one hose going there and suddenly everything was back in working order! It now works like it should again!
Looks like I bought the new actuator for nothing... It cant hurt to have a spare though, as they are pretty fragile and even failed when new in 1967... In the meantime I might also find a way to install the original rod ends... Let me know if you have an idea!

If you are looking for a vacuum diagram for the Eldorados headlight doors you can find it on my website.

on the left the original actuator - on the right the reproduction unit from a 1969 Camaro RS


The different rod ends - the original one on the left - the headlight door mechanism is installed in the center of the rod end with a pin.
On the Camaro unit one could probably install it on the side using a bushing.
I have heard that this worked fine for some Eldorado owners as you can see on the picture below.


This is how it worked for another Eldorado owner - he installed some bushings on the new unit.
I found this picture on ebay at the auction for a 1967 Eldorado recently.

Update November 2014:

I have been in contact with Mark Maromonte who found this post on my website and replaced his bad OEM actuator with the 69 Camaro RS unit. He did some modifications and sent me some pictures to share here. Thanks Mark! I´m sure its helpful to others as well:
Mark wrote (all pictures below were provided by © Mark Maromonte):

I bought an actuator for a 1969 Camaro  RS. I removed the two pins that held the attachment to the end of the rod. Then I cut 3/8 of a inch of the rod off, so the rods were the same length. Then I beveled the end of the rod on a grinding wheel, for about a ½ inch at the end of the rod. This was done so that I could start a ¼ tap on the end of the rod. After the tap was done. I threaded on the Eldo clevis pin. Done! 20 minuets, $76 vs $245. Works fine. Thanks again for suggesting that in your post. Take care, Mark

The 1969 Camaro RS headlight actuator is slightly different from the original Cadillac actuator. It can be made to fit though.


The original Cadillac OEM actuator on top and the Camaro RS actuator below. You can see the difference on the mounting. Also the air outlet is slightly curved on the Camaro. There is a thread on the Cadillac actuator and a clevis pin on the Camaro rod end.


The original Cadillac OEM actuator on top and the Camaro RS actuator below. You can see the difference on the mounting. Also the air outlet is slightly curved on the Camaro. There is a thread on the Cadillac actuator and a clevis pin on the Camaro.


Mark beveled the end of the rod on a grinding wheel, for about a ½ inch at the end of the rod.


Mark cut a thread onto the Camaro shaft so that the original Cadillac clevis would fit.


Finished- works perfectly. The modification is done.

Tags:1967, Eldorado, 1967 Cadillac Eldorado Repair Tip, Headlight Actuator, Headlight doors, Restoration, Camaro RS, Vacuum hoses