1968 Headlight Switch...Vacuum or no?
Thread Starter
Drifting
Joined: Nov 2013
Posts: 1,572
Likes: 486
From: Loud, Raw and Dangerous 1968 327 4S in Southern California
1968 Headlight Switch...Vacuum or no?
Bought a new headlight switch and noticed that it does not have the vacuum hose connections on the switch. Vendor provided this switch specifically for my 1968 which is an AC Delco / GM part number 19106986. Most all the vendors and the web diagrams show this connection in their pictures and I am wanting to verify I got the right one for my car before I start to take apart the dash.
Thanks in advance for any advice...
Thanks in advance for any advice...
Melting Slicks
Joined: Mar 2005
Posts: 2,095
Likes: 299
From: Midlothian VA
Bought a new headlight switch and noticed that it does not have the vacuum hose connections on the switch. Vendor provided this switch specifically for my 1968 which is an AC Delco / GM part number 19106986. Most all the vendors and the web diagrams show this connection in their pictures and I am wanting to verify I got the right one for my car before I start to take apart the dash.
Thanks in advance for any advice...
Thanks in advance for any advice...
Good info posted here
Thread Starter
Drifting
Joined: Nov 2013
Posts: 1,572
Likes: 486
From: Loud, Raw and Dangerous 1968 327 4S in Southern California
Interesting...my 19106986 switch has 8 pins not 7 as show in the diagrams. I wonder if this extra connection (pin 7 on the part) is for an electrical connection to open a headlight bucket valve. Before I rattle the cage at the vendor I will take out the dash screws, pry the dash open a bit by the door, and look and see if there are any hose connection to the switch. Thanks for the info.
Thread Starter
Drifting
Joined: Nov 2013
Posts: 1,572
Likes: 486
From: Loud, Raw and Dangerous 1968 327 4S in Southern California
What a mess....some vendors show parts with the vacuum ports, some don't have it, some have 7 pins, some have 8 pins, one even had the extra pin 7 and the vacuum ports. At lease 5 different GM part numbers. They all say it fits my 1968 year car however I am seriously doubting at this point that anything without the vacuum port is not going to work in my car.
Le Mans Master
Joined: Jan 2001
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Just go to that Willcox link above and see if your part is as stated there. If not, then return it and get your parts from Willcox. They know what they're doing. http://repairs.willcoxcorvette.com/?...eadlamp+Switch
I ordered my 68 light switch from Mid-America (now mamotorworks) like 17 years ago and I haven't had any problems. Everything hooked right up and it came with all the appropriate vacuum connections. Take a look: https://www.mamotorworks.com/corvett...witch-632005-1
1995166 superseded by the 1995191....which is the part mentioned in the mamotorworks link.
http://gmpartswiki.com/getpage?pageid=23572
I ordered my 68 light switch from Mid-America (now mamotorworks) like 17 years ago and I haven't had any problems. Everything hooked right up and it came with all the appropriate vacuum connections. Take a look: https://www.mamotorworks.com/corvett...witch-632005-1
1995166 superseded by the 1995191....which is the part mentioned in the mamotorworks link.
http://gmpartswiki.com/getpage?pageid=23572
Last edited by carriljc; Jan 26, 2020 at 12:06 AM.
Melting Slicks
Joined: Mar 2005
Posts: 2,095
Likes: 299
From: Midlothian VA
Interesting...my 19106986 switch has 8 pins not 7 as show in the diagrams. I wonder if this extra connection (pin 7 on the part) is for an electrical connection to open a headlight bucket valve. Before I rattle the cage at the vendor I will take out the dash screws, pry the dash open a bit by the door, and look and see if there are any hose connection to the switch. Thanks for the info.
The electrical side of the switch is for the dash lights, interior lights, headlights, markers, and tail lights.
Is my vette stock?? HAHA
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From: Im not allowed to tell you
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Before you buy a headlight switch or a wiper switch for your 68 talk to Ernie at Willcox. He tests his switches and knows what hes talking about. The newer parts manufacturers arent the same as they were 10 or more years ago.
some of the other venders dont test and dont know about 68 only parts. Your switch definitely should have the vacuum ports. Theres a lot of bad switches out there that are bad right out of the box from china so test it before installing it. THe vacuum switches fail, the dimmer part fails and on the wiper switches the whole thing can fall apart after 2-3 uses. I ended up buying a used wiper switch from a vette recycler here on the forum. I have a headlight switch from Willcox in the car now.
Mid years (63-67) had electric motors for the headlights. Also you should know your radiator support, some steering and front end parts are 68 only and are actually 67 parts. There are alot of companies that say 68 thorough 82 and should be 68 through 72 or 68 only so be aware and deal with supply houses that actually know what you need. Paragon and Keenparts have really good parts diagrams as well
some of the other venders dont test and dont know about 68 only parts. Your switch definitely should have the vacuum ports. Theres a lot of bad switches out there that are bad right out of the box from china so test it before installing it. THe vacuum switches fail, the dimmer part fails and on the wiper switches the whole thing can fall apart after 2-3 uses. I ended up buying a used wiper switch from a vette recycler here on the forum. I have a headlight switch from Willcox in the car now.
Mid years (63-67) had electric motors for the headlights. Also you should know your radiator support, some steering and front end parts are 68 only and are actually 67 parts. There are alot of companies that say 68 thorough 82 and should be 68 through 72 or 68 only so be aware and deal with supply houses that actually know what you need. Paragon and Keenparts have really good parts diagrams as well
Last edited by Rescue Rogers; Jan 26, 2020 at 08:57 AM.
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Thread Starter
Drifting
Joined: Nov 2013
Posts: 1,572
Likes: 486
From: Loud, Raw and Dangerous 1968 327 4S in Southern California
Yes...I should have known better. I like the low prices from Rock Auto and have not had any parts problems until this issue. Don't buy the switch from them right now as they will send you the wrong one and want you to pay part of the shipping costs even though it was their mistake.
Last edited by Redvette2; Jan 26, 2020 at 01:40 PM.
Thread Starter
Drifting
Joined: Nov 2013
Posts: 1,572
Likes: 486
From: Loud, Raw and Dangerous 1968 327 4S in Southern California
Le Mans Master
Joined: Jan 2001
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Save/Bookmark this link: http://gmpartswiki.com/query
You can look up old part numbers, trace superseding numbers, and validate and/or check information on parts that you locate elsewhere. Not the most user-friendly thing, but it's actually quite useful after you play around with it a few times.
I have also noticed that rockauto is pretty good a identifying something from a part number....but you have to validate what you find there with something else.
Quite a few chevy/gm parts can be used on c3 corvettes, but when you get into the weird stuff, like the vacuum operated contraptions, you want to go to Corvette specific parts providers.
You can look up old part numbers, trace superseding numbers, and validate and/or check information on parts that you locate elsewhere. Not the most user-friendly thing, but it's actually quite useful after you play around with it a few times.
I have also noticed that rockauto is pretty good a identifying something from a part number....but you have to validate what you find there with something else.
Quite a few chevy/gm parts can be used on c3 corvettes, but when you get into the weird stuff, like the vacuum operated contraptions, you want to go to Corvette specific parts providers.
Last edited by carriljc; Jan 26, 2020 at 04:26 PM.
Former Vendor
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The delco replacement switch doesn't have the vacuum switch incorporated into the switch.... it's a common problem that you'll run into with all suppliers even your local parts store. The interchange number is not correct.
Willcox
Willcox
Thread Starter
Drifting
Joined: Nov 2013
Posts: 1,572
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From: Loud, Raw and Dangerous 1968 327 4S in Southern California
Update: Got the right switch with the vacuum ports and installed it....easy to do. Just removed the two side screws and the three top screws on the dash panel and pulled the panel out a bit. Rod and **** did not want to come out with the button pushed so I gave the rod a small shot of WD-40 from the front (with the switch in the lights on position) and it came right out.
Nice to have dash and interior light control again.
More Info: After first installing the new switch the buckets did not rise....thought I had screwed up. Tracing the vacuum lines forward to the front I found not one but two vacuum lines detached. One at the passenger actuator and one at the center control relay valve (it had been a while since I drove at night). Fortunately plugging them back in everything works again. After looking at the various headlight vacuum system schematics, I realized a PO had removed the filter and check valve. $50 later I will soon receive some new parts to install.
Nice to have dash and interior light control again.
More Info: After first installing the new switch the buckets did not rise....thought I had screwed up. Tracing the vacuum lines forward to the front I found not one but two vacuum lines detached. One at the passenger actuator and one at the center control relay valve (it had been a while since I drove at night). Fortunately plugging them back in everything works again. After looking at the various headlight vacuum system schematics, I realized a PO had removed the filter and check valve. $50 later I will soon receive some new parts to install.
Last edited by Redvette2; Feb 7, 2020 at 10:58 AM. Reason: More Info...