I've been going through the many headlight vacuum threads and have made progress on my system but before I take the next step im looking for a little advice. The last owner had pulled one of the relay valves and blocked the hoses so I got a new relay and hooked everything back up.
Before this, I just manually raised and closed the headlights, but now I can only raise them when the manual override switch is pulled. Then I can push the switch and the lights will go down.
I don't have a vacuum pump so before I try to get one and start troubleshooting can anyone suggest a solution to the current problem? Actuator seals? Valves/filters? It feels like I'm so close and that it could be an easy fix. Thanks.

 

If you have good lungs you can suck the headlights up and down to test the circuit, at least that's what I did as I didn't have a vac pump:-)

 

you do have a vacuum pump, just start the engine. You'll need a vacuum circuit diagram. Seem like the actuators work if using the manuel override make them go up and down. check to see if vacuum signal changes at the headlight valve the same when operating the override and the headlight switch. a vacuum guage helps to determine the amount of vacuum you have. the hoses deteriate with age, hose ends split,ect. causing low vacuum and loss of function. Look at the headlight switch to make sure the hoses are attached and routed correctly to and from the override switch.

 

OK, Here goes....

The vacuum pump is the best way to diagnose your system, one component at a time. However, you don't have one, so the next step is to borrow one. The Autozone stores in my area loan these out with a deposit which you get back when it's returned. If you want another way to test the major components, follow along.....

I think I know what your problem is, but first I suggest you start checking in this order. You know how to raise and lower the lights manually, so that's what we will focus on to start. NOTE; All tests are with the engine off.

Pull the vacuum hoses off the actuators front and back. Move the headlights up and down from full down to full lock. Be careful to support with it one hand while the other does the work. Don't slam or get body parts caught anywhere as the lights should move rather freely. Now, with the lights in the down position, plug the back (toward the back of car) vacuum outlet with a small piece of plugged tubing. Try to raise the headlight. If you can with the same effort as not plugged, the actuator is junk. If you cannot raise it, remove the plug and raise the headlight. Repeat for each side.

Put the plugged tube on the front of the actuator to seal that side, and do the same test, only try to lower the headlight. You should not be able lower it. If you can, your actuator may be able to be repaired with a new front seal. You can find them at Willcox. You will have to remove the actuator to do this. Repeat for each side.

Next, test the relays. Disconnect the vacuum hoses and find a clean two foot section to blow through. Connect one end to the center outlet of the relay. Plug the bottom outlet with your finger, and try to blow through the hose. You should not be able to do it.

I have found almost all headlight problems can be diagnosed this way. Try it and report back, we'll go from there.

 

while I'm sure it was wrong on many levels, i used a vacuum cleaner. just enough to check everything. just another method

 

Ok thanks guys, that gives me a place to start before I go find a vacuum pump. I'll try Dave's method since it would be helpful to know if my actuators are shot first. I know the information is out there so thanks for taking the time.