One of the most read articles on my website is about how to repair the somewhat troublesome headlight actuators on the 1967 and 1968 Cadillac Eldorado.
After many years they tend to fail for many owners of the 1967 and 1968 Eldorados.
One company has offered a reproduction, but from the experience some people made with it, it was said that it was very poorly made and extremely expensive. I can´t tell anything about it from my own experience though.

But there is a better and much cheaper solution to the problem in the form of a modified reproduction 1969 Camaro RS actuator which is readily available. I´ve written an article a couple of years ago what could be done and I have now updated it, as one reader sent me some excellent description and pictures of how he modified the Camaro actuator to work perfectly on his 1968 Eldorado.
Thanks for the tip Mark Maromonte from Marks Truck and Auto Repair.

Click on the picture to go to the updated article.

Tags:1967, 1968, Cadillac, Eldorado, Restoration, Headlight Actuator, Headlight doors, 1967 Cadillac Eldorado Repair Tip, Vacuum Schematic, Vacuum diagram, Vacuum hoses, Vacuum Valve

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

I brought my 67 Eldorado home from the restoration shop yesterday only to find out that the AC compressor died and leaked the fresh refill it got. Everything is new except the compressor and of course it died at the first usage. The system was pressure tested at the shop and worked like a charm. When they let the car idle with the AC on, the compressor started to leak. They tried to fix it but had no success. So I will need a new compressor and a new charge.
The right headlight door actuator also suddenly no longer works correctly. All hoses are new and it worked perfectly until recently. I can now only make it close if I jiggle on the actuator. Is there any way to rebuild them? A source for new or rebuilt ones? I have heard that the ones from the 1969 Camaro is very similar and only needs some minor modifications to work on the Eldorado as well. So I went ahead and ordered one. But the worst thing was that the freshly rebuilt carburetor made strange ticking noises and sounded like a tractor while accelerating. It worked well though, but the sound was unbearable. Could it be a defective gasket? It was also idling quite badly. Acceleration was superb though, its much more powerful than before, but still something was wrong... The ignition also was completely rebuilt. So I played around with the ignition first, but the ticking sound did not go away, no matter in which direction I changed the timing... Almost sounded like an exhaust leak, but there seemed to be none... It was LOUD! Before I had the carb and ignition rebuilt, it was extremely quiet and idling smoothly but had misses while accelerating.
I got some very valuable tips from fellow Cadillac aficionados and the previous owner of this Eldorado even called me from the USA to give me some tips to solve this issue, and he was spot on with his diagnosis...

With a hose held to my ear and the other end to the carburetor, I was able to locate the source of the noise. It came from the carburetor below the choke assembly. So I took the freshly rebuilt Rochester Quadrajet out again, only to find out that the gasket and the metal shim were installed the wrong way around. This burned a hole into the brand new gasket where the exhaust gases from the heat crossover passage could escape and make this noise.
Of course I did not have a new gasket at hand, so I carefully removed the old one from my spare engine, which was in pretty good shape and installed it.
No more ticking - no more noises, no more bad idling.
The car now drives amazingly good and is silky smooth. It could not be any better.

The shim was installed first and then the carb - thats wrong! The gasket has to go on the intake manifold first - then comes the metal shim.


Here you can see the burnt gasket and the metal shim


Putting everything back together again


Test drive after the repair - perfect!

Tags:1967, Eldorado, Restoration, Carburetor, Rochester, Quadrajet, Headlight doors, 1967 Cadillac Eldorado Repair Tip, Headlight Actuator, AC Compressor, A6

As we had an unusual warm day today with the snow melting in front of the garage, and having a couple of hours of spare time at hand, I decided to drive the Eldorados out of the garage. They both started right up as soon as the fuel pump delivered fuel to the fuel bowl. Both cars idled beautifully and it was a pleasure to see them in the bright daylight again for the first time since last October when I had put them into storage.

While I had the 67 Eldorado out I also turned on the headlights and was once again annoyed by the fact that the right one opened simultaneously, but closed slightly slower than the left one when I turned the lights off. There was a difference of around 1 second in movement between the two headlight doors.
Being a perfectionist I could not stand this, so I began searching for the problem. I already had spent some time in the past trying to fix this, but I did not succeed. The system is driven by vacuum only, so I started to look through the vacuum hoses once again. I had already exchanged a couple of them last year. I found another two brittle ones going through the firewall to the headlight switch from where a slight hissing sound was coming when the lights were on. When I touched them the hissing would become even more noticeable. I then tried to press them onto the connector of the switch and the first hose began to crumble into pieces. So I replaced all the hoses on the switch and rerouted them through firewall through the rubber insulation. There are three hoses . One is the vacuum feed (the one in the middle - I think it was yellow), one is for opening the doors (green) and one for closing (red). I also replaced the red hose behind the firewall going to a T-connector from where the vacuum is fed to the headlight door actuators. I had already replaced the two hoses after the T-connector in the past. With all new hoses in place the doors now perform almost simultaneously and quite fast. So when you run into troubles with your headlight doors, check and replace all the according vacuum hoses first. Its amazing how brittle the hoses going to the headlight switch inside the car can become over the years. It looks like they used a quite different material for these three hoses, as all other vacuum hoses are in much better shape and do not show any sign of deterioration at all.
You can see a video of the headlight doors in action below. On this video they are slightly out of sync. As it looks like they are slightly different every day, depending on temperature and engine idle...

watch on youtube or below

the vacuum diagram for the headlight doors


The vacuum diagram for the headlight doors

While the Eldorados were outside the garage my wife used the opportunity to shoot a couple of pictures she had in her mind, which she is planning to hang into the kids room. Cant wait until the medium format film is back from the photo lab. Below you can see only some digital snap shots I took.
Despite the last two unusual warm and beautiful days unfortunately winter is not over yet here in Austria, as some more snow is predicted for next week and the cars are back in the garage desperately waiting for April to come...

The Eldorado is enjoying some sun rays for the first time this year

Although she is 7 months pregnant, my wife Afra is still climbing ladders to get the best angle for her shots...

The two Eldorados in front of the garage where the snow has just melted away.

Tags:1967, Eldorado, Headlights, Actuators, Headlight doors, Video, Vacuum diagram, 1967 Cadillac Eldorado Repair Tip, Restoration, Vacuum hoses