Pulling up headlight doors without eng. running?
Melting Slicks
Joined: Mar 2005
Posts: 2,094
Likes: 298
From: Midlothian VA
You can raise / lower them by hand. If you need them up you should be able to reach under/behind the headlight and pull the support into the locked position.
Melting Slicks
Joined: Mar 2007
Posts: 2,520
Likes: 11
From: Hinckley OH
Yep, you can move the linkage from under the car. Just be careful that your fingers don't get caught.
Thread Starter
Melting Slicks
Joined: Jun 2011
Posts: 2,096
Likes: 15
Hi alc,
Even with the engine off IF the vacuum hoses are still connected to the actuators (large green and red striped hoses) you should still feel some 'push back' as you open and close the doors by hand.
This is an indication that the system is still 'sealed', but the operating vacuum is low.
On a properly sealed system after you've opened the first door, as you begin to close it the other door should at least try to open to some degree. This is because the little bit of vacuum created when you opened the first door is being forced to the other actuator (it has to go somewhere as the internal diaphragm moves) as you close the first door.
Pushing the doors open and closed with the hoses still attached to the actuator is hard on the seals on the diaphragms in the actuators.
If you don't feel a difference in the effort required to cycle the doors with the hoses on or off it's an indication of a seal problem.
Regards,
Alan
Even with the engine off IF the vacuum hoses are still connected to the actuators (large green and red striped hoses) you should still feel some 'push back' as you open and close the doors by hand.
This is an indication that the system is still 'sealed', but the operating vacuum is low.
On a properly sealed system after you've opened the first door, as you begin to close it the other door should at least try to open to some degree. This is because the little bit of vacuum created when you opened the first door is being forced to the other actuator (it has to go somewhere as the internal diaphragm moves) as you close the first door.
Pushing the doors open and closed with the hoses still attached to the actuator is hard on the seals on the diaphragms in the actuators.
If you don't feel a difference in the effort required to cycle the doors with the hoses on or off it's an indication of a seal problem.
Regards,
Alan
Melting Slicks
Joined: Mar 2005
Posts: 2,094
Likes: 298
From: Midlothian VA
Thanks Alan yep it does exactly what you decribe so that's pretty normal then I take it?? Now when I first start the car the headlights will go up about an inch then retracts back down and my understanding is because the vacuum is lost. Is that right?? When the car is running the operation is fine and works good. I do have reproduction actuators and when checked with a mighty vac they do bleed down but very slowly. Is there such a thing as perfect actuators?
Thread Starter
Melting Slicks
Joined: Jun 2011
Posts: 2,096
Likes: 15
Thread Starter
Melting Slicks
Joined: Jun 2011
Posts: 2,096
Likes: 15
Hi alc,
If the problem doesn't prove to be the check valve I'd test the relay's operation and the connections at the relay next.
The system is designed so that on a normally operating system even if all the vacuum is lost while the engine is not running, upon start-up the doors should stay exactly where they are. They shouldn't "dance" or "wink".
This is because the 'control' side of the system (switch, relay, small hoses), requires less vacuum to operate than the 'servo' side of the system (actuators, large hoses).
Regards,
Alan
If the problem doesn't prove to be the check valve I'd test the relay's operation and the connections at the relay next.
The system is designed so that on a normally operating system even if all the vacuum is lost while the engine is not running, upon start-up the doors should stay exactly where they are. They shouldn't "dance" or "wink".
This is because the 'control' side of the system (switch, relay, small hoses), requires less vacuum to operate than the 'servo' side of the system (actuators, large hoses).
Regards,
Alan
I have checked the system and the headlight switch, check valve, canister and relays all held vacuum. It was until I checked the actuators which bled down so I'm assuming that's where the problem lies but wanted to get your guys professional opinion
Drifting
Joined: Jul 2006
Posts: 1,259
Likes: 154
From: Deplorableville Nebraska
If you have a Mityvac you should test the entire CONTROL side as a unit. Connect the small hose at the check valve to the Mityvac. Make sure the headlight switch is pushed in off, and the override is also pushed. This creates a closed circuit from the vacuum source to the top control chamber of the relays. If there is any loss of vacuum here, it would create the problem you are having. You will have to pump for a little bit to get the circuit evacuated.
How fast do the actuators leak down?
How fast do the actuators leak down?
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Thread Starter
Melting Slicks
Joined: Jun 2011
Posts: 2,096
Likes: 15
If you have a Mityvac you should test the entire CONTROL side as a unit. Connect the small hose at the check valve to the Mityvac. Make sure the headlight switch is pushed in off, and the override is also pushed. This creates a closed circuit from the vacuum source to the top control chamber of the relays. If there is any loss of vacuum here, it would create the problem you are having. You will have to pump for a little bit to get the circuit evacuated.
How fast do the actuators leak down?
How fast do the actuators leak down?
Thread Starter
Melting Slicks
Joined: Jun 2011
Posts: 2,096
Likes: 15
If you have a Mityvac you should test the entire CONTROL side as a unit. Connect the small hose at the check valve to the Mityvac. Make sure the headlight switch is pushed in off, and the override is also pushed. This creates a closed circuit from the vacuum source to the top control chamber of the relays. If there is any loss of vacuum here, it would create the problem you are having. You will have to pump for a little bit to get the circuit evacuated.
How fast do the actuators leak down?
How fast do the actuators leak down?
When you say the override is pushed do you mean in override position or normal position?
Thread Starter
Melting Slicks
Joined: Jun 2011
Posts: 2,096
Likes: 15
Well I just checked what you suggested and this is how it went. I connected the Mighty Vac to the small vac line off of the check valve with the headlight sw. in the off position and the override in the normal position. Pulled a vacuum almost immediately and stayed, did not leak down so I now switched to the larger hose coming off of the check valve and was able to bring up the left headlight fairly quick. I continued to pump and pump and the right headlight never came up and gave up since my arms was cramping up. Was the right headlight suppose to come up as well?
Drifting
Joined: Jul 2006
Posts: 1,259
Likes: 154
From: Deplorableville Nebraska
Was the right headlight suppose to come up as well?
Recheck the actuator this way. Remove the actuator vacuum hoses, and manually raise the headlight. Connect the Mityvac to the front port on the actuator and pump it up. It should hold vacuum. This is the side that raises the headlight. If that passes the test, lower the headlight, and connect to the rear actuator port and pump it up. This side should now hold vacuum.
Next check the relay this way. Mark and remove the middle and lower vacuum hoses from the relay. Connect the Mityvac to the middle port. Block the lower port with your finger, and pump it up. It should hold vacuum until you remove your finger.
Let us know how it went.........Dave
Thread Starter
Melting Slicks
Joined: Jun 2011
Posts: 2,096
Likes: 15
Yes, the right one should come up with the left headlight as well. We now know that the control side is vacuum tight. That means the switches (headlight, override, and relay) are good. The only other components to check are the right side relay and actuator.
Recheck the actuator this way. Remove the actuator vacuum hoses, and manually raise the headlight. Connect the Mityvac to the front port on the actuator and pump it up. It should hold vacuum. This is the side that raises the headlight. If that passes the test, lower the headlight, and connect to the rear actuator port and pump it up. This side should now hold vacuum.
Next check the relay this way. Mark and remove the middle and lower vacuum hoses from the relay. Connect the Mityvac to the middle port. Block the lower port with your finger, and pump it up. It should hold vacuum until you remove your finger.
Let us know how it went.........Dave
Recheck the actuator this way. Remove the actuator vacuum hoses, and manually raise the headlight. Connect the Mityvac to the front port on the actuator and pump it up. It should hold vacuum. This is the side that raises the headlight. If that passes the test, lower the headlight, and connect to the rear actuator port and pump it up. This side should now hold vacuum.
Next check the relay this way. Mark and remove the middle and lower vacuum hoses from the relay. Connect the Mityvac to the middle port. Block the lower port with your finger, and pump it up. It should hold vacuum until you remove your finger.
Let us know how it went.........Dave
Ok the right actuator will pull a vacuum on both ports but immediately drops after pumping but can achieve 20" of vac. The relay holds perfectly so that's not a problem. Now just for sh*ts and giggles I did the same to the left actuator and the rear port held vacuum but the front or bottom could not even pump up at all. This sucks cause both of these are new, well new on the car I bought them last year.
Drifting
Joined: Jul 2006
Posts: 1,259
Likes: 154
From: Deplorableville Nebraska
Ok the right actuator will pull a vacuum on both ports but immediately drops after pumping but can achieve 20" of vac. The relay holds perfectly so that's not a problem. Now just for sh*ts and giggles I did the same to the left actuator and the rear port held vacuum but the front or bottom could not even pump up at all. This sucks cause both of these are new, well new on the car I bought them last year.
Thread Starter
Melting Slicks
Joined: Jun 2011
Posts: 2,096
Likes: 15
Looks like you found the source of your problem, or at least the biggest one. Replacing the front seal is relatively easy, you just have to pull the actuator out. I've found that vacuum (or actually atmospheric pressure) commonly follows the path of least resistance, just like electricity. Because you have an open seal, the balance between the control and actuating circuits behaves erratically. Your slowly leaking actuators are continually recharged by vacuum from the engine when running, but the 1 big open leak weakens that signal.
Drifting
Joined: Jul 2006
Posts: 1,259
Likes: 154
From: Deplorableville Nebraska
Yep now if I can get a new one that will hold vacuum. Thanks a million for your help.