hey guys, well I have been trying to figure out the headlight problem and found that the relays needed to be replaced, so I did that and when I was testing the headlights to go up and down, only the passenger side goes up and down fluidly, and the drivers side creeps up 1/4th of the way up and then slowly goes back down. Would this imply that I need a new actuator or a new seal? I tried to lube the grears a bit and it didn't help much. Any ideas are appreciated!

 

any headlight and vacuum experts out there?

 

Have you tested your vacuum system for leaks? There are a lot of places the vacuum can leak out and you lose things like headlights and breaks. A $30 vacuum gun from Autozone will help you test your systems at the carb and headlights.

 

If you have access to a vacuum pump, a vac gage, and some time you can test each part of the system.
You replaced the relays, so start by checkingto see that the vacuum lines are fully installed on the relays. Then check to see they are seated fully on the actuators and not leaking ecause sometimes just moving the hoses around breaks the seal and causes problems.

It sounds like you have a bad actuator though.
to test using the engine as your vacuum source. Start the car and let it idle
1. disconnect the primary vac line from the carb or intake manifold.

2. connect the vac gage in it's place and take a reading. This will tell you your max available vacuum. Depending on your cam it could be <5 to >15 inches of Mercury

3. reconnect the primary vacuum line to the source

4. disconnect the RED vacuum hose from the back of the actuator and measure the vacuum to that hose with the headlight switch on. It will be a little less than manifold vacuum number, but it shouldn't be a lot less. If it's a lot less there is something leaking between the manifold connection and the headlight. Work your way backwards one hose at a time until the vacuum increases to near manifold vac number.

5.reconnect the RED hose to the back of the actuator

6. disconnect the GREEN hose from the headlight RELAY and measure the vacuum on the front of the headlight actuator with the headlights on. It SHOUD BE ZERO or near ZERO
If you have vacuum on the front side, you have a bad headlight actuator. The diaphragm is torn.

 

Thats a good method Tom. Thanks.. I personally want to meet the guy/guys who decided to put these Vac. systems in the Corvette's so I can kick them square in the nuts..

 

the problem isn't really with the design of the vacuum system; it's the age of our cars. things get worn out. Think about how many times the headlights have been turned on/off in the last 30 to 40 years.
The rubber bits are just past their useful life expectancy.
The real PITA is that we have to but several hundred dollars worth of replacement assemblies instead of ten or twenty dollars worth of parts.

 

I don't mean to highjack this thread.
I posted a poll in the C3 parts forum to gauge interest in whether or not to create and market a cheap healight relay repair kit
please take the poll. If there's sufficient interest, I'll have tools built and start selling kits to save us all some bucks.

 

A friend recently bought two new relays from Ecklers and found that they only operated the headlights twice before they stopped working. It seems that in both relays the center valve froze in place and would not move. They both appeared to have some lubricant on them, but they just would not move.

He was able to free them up by using some synthetic motor oil on them. Unfortunately because they were both new ones, he wasted a lot of time troubleshooting before he came back to the new relays.

One additional thing regarding relays, they come with a small square foam filter in the open end of the relay. This is to help keep debris out of the relay. Since it has vacuum on it whenever the engine is running, it will want to pull air around the seals. If your filter(s) are gone, just cut a small piece of foam to put in there to help keep dirt out and make them last longer.

Good luck... GUSTO

 

Another member (Tommy Samuels) provide this link. Check it out, it has a diagram and very detailed instruction. It helped a lot. http://www.corvette-101.com/vacuum.htm

 

I don't think it's a vacuum leak, but I didn't really go over the entire system, nor did I use a vacuum gauge. I was presuming that since I was getting vacuum at both the relays and I followed the lines to make sure there weren't any visual cuts or anything in the hoses that it must be the actuator. But again, I'm no technician. I appreciate all your comments you guys, this place has been really helpful in fixing my vette. Tom - thanks for that procedure, I'll do that before I get a new actuator to make sure.