I just bought a new vacuum hose kit from Ecklers because I am having trouble with my head lights popping up. everything was going good until I got to hooking up the hoses to the manifold. I have all different kinds of connections off my engine that are not in the vacuum hose diagram that came with the kit.

For instance, the main vacuum hose coming from the vacuum tank in the picture goes inside the firewall to the heater and ac control and then out to a metal valve in the engine compartment. My engine does not look like this.

I have to assume mine is jerry rigged so I am wondering if anyone has the correct vacuum hose diagram for a 1979 corvette L48. I have the corvette shop manual and the haynes manual and they are not much help.

 

Will this help? PG.

[IMG]local://upfiles/2883/62FFE112815543C89CC428D4535F576E.jpg[/IMG]

 

PG
Yes it will help. SCHOON helped to, I need to pull the dash and trace two hoses and replace them. They are 2 very small ones that enter the firewall over on the passenger side. They are all brittle and keep breaking.

 

I replaced all the vacuum lines and the lights will still not come up on their own. They need just a little pull and then they pop up and click into place. Plenty of vacuum, not sure what the problem is. Could it be the springs on the lights? They look original.

 

Hi again, here's a few things you can do:
First lets check to see if the "Actuators" work. Disconnect the vacuum system at the manifold and run a line to the front of theleft actuator, start your car and see if the light comes up. Then remove that line and put on the rear port and see if it goes down. If it does than that side is OK.
Then do the same test on the right side.
If there both good than check the relays:
There are 4 connections, 1 at the big part on the top and 3 others.
Connect the test line to the second from the bottom. That should make the light on that side go up. Than connect to test line to the top connection, that should make the light go down.
You can put a little penetrating oil in each relay port, that made mine go a lot faster.
If the tests work but the lights still don't work from the headlight switch than get a vacuum guage and see how much vacuum you have at the manifold and work your way thru the system untill you find the leak. PG.

 

Normally when the lights don't come up, it's the sealing gromet, when they won't go down, it's the actuator. I posted the site; http://www.corvette-101.com which covers this problem.

 

The information in the text it good, however that diagram is WRONG!
At the headlight switch the hose connection closest to the firewall has to go to the bottom connection on the pull down switch. PG.

 

I ment no disrespect. You tried in good faith to help out another forum member, and that's what this forum is about. There are manywrong diagrams on the net, and very few that are correct.

The vacuum system is hard enough to fix, and when we see something published, we assume it will help, unfortunately that is not always the case.

Have a Happy July 4th, PG.

 

pg,
Is the diagram wrong for the year 'Vette that they refer to on that site/ Or for the later year 'Vette? I used the site totroubleshoot my circuit w/ the vacuum pump and the tests were "to the point" and correct. I do understand that if you don't have that year 'Vette, the diagram may be wrong. But from riley'slast post, he was past the diagram.
And going from that first post riley put up on to the second, and third which states that he has vacuum and lights still not coming up,he should go on to test the components, which is what that site goes into.
Sounds like you skipped riley'sthird postor you're tripping onthe diagram in the site which has nothing to do w/ where riley explains he's at after getting vacuum to the lights. His third post sounds to me like he now has vacuum to the lights and still the lightsare not coming up like they should. Therefore I said, "go to "the site I posted" and troubleshoot the components."
Were you "on the rag" theday you posted those two? I hope you're now over it.

 

One hose goes to the heater thumb wheel, the other goes to the headlight switch. I felt that if R6R or SCHOON went thru the trouble to pull the dash apart then they should have the correct diagram.
The diagram I posted is good for 73 to 79 C3's. PG.