C-3 68-82 Headlight Switch Vacuum Rebuild Step by Step

[Rich P.]

Ok here's the deal. I have completly had it with reproduction headlight switches. Be it C-2 or C-3 or First Gen Camaro I find that I go through 3-4 new switches untill I give up and rebuild the old one. Some of the problems are incorrect terminal slide locations, poor workmanship in assembly or headlight pull rods that won't catch no matter what trick I do. So I have resorted to rebuilding the old switches if and when possible.

One thing I have not tried until today was to rebuild the vacuum side of the headdlight switch. I am assembeling a 69 Camaro pace car and had electical trouble with the repro headlight switch so I cleaned and installed an original switch. That took care of my electrical gremlins but as I was setting up the rally sport headlight system (which runs on the same principals as the corvette headlight system) I found the vacuum side of the original switch to be defective. I was able to rebuild it with the new parts from the repro switch.........so if you guys don't mind I'll post a very easy step by step process of the rebuild. This way some of you may be able to save your original switches.

Rich

[Edward J.]

Re: C-3 68-82 Headlight Switch Vacuum Rebuild Step by Step

Rich, I know where your coming from, being in the automotive trade, I See this all the time, the things is the GM factory headlamp switch its self is a pretty reliable part, Its the reostat that is trouble, and the switch its self is a prettry easy part to take apart and clean the contacts, I do not think the vaccum part of the switch is a big part of the failure for corvettes.

The venders that sell the repro switchs relay on the quality control of the manufacturers, which is not a good thing, and when we do have a part go bad we end bearing the cost to return the part most of the time.

[Keith L.]

Re: C-3 68-82 Headlight Switch Vacuum Rebuild Step by Step

With 3 69 Camaros with RS and two c3s I'm all ears as I used my last nos Camaro switch two years ago. And how would you test the vacuum side of a used one off the car?

[Rich P.]

Re: C-3 68-82 Headlight Switch Vacuum Rebuild Step by Step

Kieth,

at the end of the thread I will have the off car test for the vacuum operation. Any Rat motors or high winding small block with those headlight coverd cars?

Ed,

I agree tha vacuum part does not go often but when it does this can save an other wise bad switch.

Rich

[Clem Z.]

Re: C-3 68-82 Headlight Switch Vacuum Rebuild Step by Step

if it is the electrical contact problems would the old fashion TV tuner cleaner work to clean up the problem without taking the switch apart ?

[Rich P.]

Re: C-3 68-82 Headlight Switch Vacuum Rebuild Step by Step

The vacuum section of the switch is located on the underside and is the rectangular section with the 2 ports.

First thing to do is to pry open the 6 retaining tabs to allow removal of the parts. That is done easily by prying with a flat blade screw driver.

Once the tabs are clear you can remove the pot metal cover plate, the rubber insert, the rubber insert reinforcement, the tension spring and finally the slider/retainer.

On this switch the center tang on the slider/retainer was broken. This did not allow the doors to open or close with the headlight switch. The doors did open and close with the override switch on the top of the relay (on Camaros) The reason the doors would not open is because when the switch is pulled into the on position it allows the air to bleed of in the vacumm line going to the relay and that allows the inner plunget to move from the closed position to the open position.

[John H.]

Re: C-3 68-82 Headlight Switch Vacuum Rebuild Step by Step

With 3 69 Camaros with RS

Keith -

Just one here, but no winky-blinkies on mine; fun, aren't they?

[Rich P.]

Re: C-3 68-82 Headlight Switch Vacuum Rebuild Step by Step

More pictures of both switches disassembled.

[Rich P.]

Re: C-3 68-82 Headlight Switch Vacuum Rebuild Step by Step

Here you can see the slider/retainer that was broken. The center tang is what gets inserted into the slide of the switch terminal that moves the internals and allows the vacuum to go to the proper ports.
Once I removed everything from both switches I cleaned the old dried grease from the original switch and re greased it. I then started to assemble the old switch with the new guts.

[Rich P.]

Re: C-3 68-82 Headlight Switch Vacuum Rebuild Step by Step

To make sure the slider is correctly located in the housing you need to move it fore and aft. At the end of the travel in both directions the slide will stop just before it contacts the switch housing. Next it is time to install the spring

[Keith L.]

Re: C-3 68-82 Headlight Switch Vacuum Rebuild Step by Step

[Rich P.]

Re: C-3 68-82 Headlight Switch Vacuum Rebuild Step by Step

Now time to install the rubber insert and retainer. They have 2 locating tabs and holes respectively that lock them together. Finally time to install the top plate.

[Rich P.]

Re: C-3 68-82 Headlight Switch Vacuum Rebuild Step by Step

Finally time to bend all 6 retaining tabs back on the top plate and test.
in order to test the switch off the car you need a hand vacuum pump. The port closes to the on off pull handle has full vacuum 100% of the time regardless of the pull rod position. So put the test hose on the front port have the pull rod out (headlights on position) then try pump up and see if it holds vacuum. next leave vacuum in the switch and push the knob all the way in (headlight off position) and immediately you will lose vacuum. Re pete the test a few times. If the results are as mentioned you now have a good working vacuum side of the headlight switch.

Any questions please feel free to ask.
Hope this helped, Rich

[Rich P.]

Re: C-3 68-82 Headlight Switch Vacuum Rebuild Step by Step

Keith,

is that a real Z-10? I have a customer who has a 396 Z-10.

Rich

[Terry M.]

Re: C-3 68-82 Headlight Switch Vacuum Rebuild Step by Step

Ok here's the deal. I have completly had it with reproduction headlight switches. Be it C-2 or C-3 or First Gen Camaro I find that I go through 3-4 new switches untill I give up and rebuild the old one. Some of the problems are incorrect terminal slide locations, poor workmanship in assembly or headlight pull rods that won't catch no matter what trick I do. So I have resorted to rebuilding the old switches if and when possible.

One thing I have not tried until today was to rebuild the vacuum side of the headdlight switch. I am assembeling a 69 Camaro pace car and had electical trouble with the repro headlight switch so I cleaned and installed an original switch. That took care of my electrical gremlins but as I was setting up the rally sport headlight system (which runs on the same principals as the corvette headlight system) I found the vacuum side of the original switch to be defective. I was able to rebuild it with the new parts from the repro switch.........so if you guys don't mind I'll post a very easy step by step process of the rebuild. This way some of you may be able to save your original switches.

Rich

Rich,

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Vinnie Peters <restorereditor@ncrs.org>