76bomb

My Bomb has a headlight issue. When I'm hammering it full throttle (ok its a 160 hp L48 auto) The left headlight opens up, yeah it's gotta be due to vacuum loss. I find it quite amusing and don't really care to invest any money into fixing it. I need a upper radiator hose more.


Hopefully this You Tube video will work. Trying to post directly with out having to "click" on a link.

I took out the gas tank to replace the rubber hoses. So I do work on it just not the silly stuff that isn't really broken.

Let me know if the video link actually works as I have not used one in a long time.

henrikse

video link works. When you have that much power you need the lights on LOL

derekderek

there is a one-way vacuum valve to stop this vacuum loss. 5 buck 5 minute fix once you find it.

63Corvette

Well...................Um, I see that your hood flew off due to the incredibly high speeds that you were running........

ignatz

I'm with you. I used to enjoy watching my wiper doors open and then close when I started the motor. Got lots of curious looks from my passengers - just getting ready to fly, I would say. Kinda like this

sullyman56

I had the same issue with my 77. It turned out to be the vacuum hoses on the headlight switch were reversed. Easy fix zero cost.

flyeri

Not fix something that's broken??? Blasphemy!!!! The rest of us think up things to fix that aren't even broken.

theandies

Rotonda

There are lot's of broken C3's out there. Why take the time to video and post yours instead of using that time to fixing it?

xpoc454

Where did you find your leak at? Mine does the same thing I belive. The wiper door goes up from the closed position at start and than goes back down.

jim

Griff2002

Same with mine, which I assumed is because my engine does not make much vacuum. However it got worse after I hooked the hoses up backwards (and then corrected), so I'm also interested in this.

billcarson

the problem here is very clear,you must leave nj immediately and you will see things more clearly.

derekderek

Switch vacuum lines on the other headlight so when you step on gas one opens, then when you lift up, the other one opens...

Tonio

https://www.corvettemods.com/C3-Corv...SABEgLTj_D_BwE

76bomb

Rotonda, to answer your question why make a video and post it. I guess I have a odd sense of humor.
Then again something good did come from this post. I now know it's a easy fix and Thanks to Chapter2 for the link and others for mentioning the check valve. People such as, xpoc454, Griff2002 and myself we can fix our cars with the simple check valve.

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C3 Corvette 1968-1982 Headlight & Wiper Door Vacuum Check Valve



Thank You Chapter2

Dave J

If you only have 1 headlight opening on a low vacuum condition, you have other issues than just simply a check valve problem. It may be a contributor, but the problem could also be the more common leaky vacuum relay or actuator seal.

The most common issue with the winking wiper door @ startup is an imbalance in the control versus actuating circuits. If you have a leaky control (small hoses) circuit, it takes an extra amount of time for the two circuits to balance out.

See 3

ajrothm

My car does this as well, always has.... and I've NEVER been able to fix it..... It ain't the check valve...

I've replaced EVERYTHING in my vacuum system, some of the parts twice, I still have various leak downs. I even vacuum tested my reservoir and it was tight.

Griff2002

I also confirmed my check valve is working. My engine has an aggressive cam so I think it takes a while to build enough vacuum when you start the car. Once I get going they stay down.