Topic: '70 vacuum hoses
in Forum: C3 General Discussion
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Manteca, CA - USA
Joined: 11/20/2005
Posts: 3623
Vette(s): 1978,two tone,Metalic Rootbeer & gold
1975 L48 4 speed
OSSW1 and myself got together recently and installed a new vacuum hose kit (w/diagram) for the headlight, w/w door actuator on one of his '70s. We covered all the bases but when you turn on the headlights the wiper door opens also and neither will close. We plan on teaming up on this again this week to correct it. Does this phenomena sound familiar to any one. Any hints might shorten our diagnostic process. I thought I remember the headlights on my '78 doing this before when I nocked a hose loose without knowing.
Jimmy B.
Just can't wait to get on the road again.
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I recently did the same but haven't tried the system yet. My kit came with a diagram as well, but I looked at many others from different internet sources.
All over the web, there seems to be confusion about the connections at the light switch.
My conclusion for the light switch is that "white" is near driver and "blue" is towards engine. See if that what you have. I also have quite a bend at the bypass switch (really wish that vacuum line would have been 2 inches longer). See if you have one bend.
I don't have a vacuum door, so can't help you much here. Regardless, you know it's the subset of the system where your headlight & vaccum hoses cross a t-connector or a bypass valve.
Good luck!
All over the web, there seems to be confusion about the connections at the light switch.
My conclusion for the light switch is that "white" is near driver and "blue" is towards engine. See if that what you have. I also have quite a bend at the bypass switch (really wish that vacuum line would have been 2 inches longer). See if you have one bend.
I don't have a vacuum door, so can't help you much here. Regardless, you know it's the subset of the system where your headlight & vaccum hoses cross a t-connector or a bypass valve.
Good luck!

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Duncanville, TX - USA
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Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/
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Perhaps the diagram isn't right, or ya just missed/crossed a couple of hoses. The only place that the wiper door and headlight vacuum hoses even come close to each other is at the over-ride knob/pulls under the steering column....that's where I think I would start..
Joel Adams
C3VR Lifetime Member #56
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Check the wiper door actuator by the brake booster..it sounds like you swapped one of those big hoses..I assume since you say none will go down you are including the wiper door..if you have a vacuum leak for the wiper door it shuts down the system..mine did something similar..wiper door went up and down and headlights..drive me nuts..was like that for at least 12 years..isolate the wiper door by pinching off the vacuum to it..or disconnect and plug it..see if your problem goes away..I got this system in my head pretty good..if you want my number I can talk ya thru it..my car is a technical 70..
Rich
Rich

My first parade at Carlisle 2010

Manteca, CA - USA
Joined: 11/20/2005
Posts: 3623
Vette(s): 1978,two tone,Metalic Rootbeer & gold
1975 L48 4 speed
Thank you gentlemen for the quick response. It's 85 mi. between us so it's not that easy to get together. Your info will give us confidence before going in and I'm sure we'll be successful. If not we'll give you a PM Rich. We're meeting on Thurs. We'll let you know how things go.
Jimmy B.
Just can't wait to get on the road again.
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Equinunk, PA - USA
Joined: 10/31/2007
Posts: 2480
Vette(s): 1972 conv, 4-speed, 350, 200hp, numbers match, rally wheels, war bonnett yellow w/white top. good condition, nice driver.
I had a slight problem with mine as well. Found out the lines were reversed at the manifold and PVC connections.

Manteca, CA - USA
Joined: 11/20/2005
Posts: 3623
Vette(s): 1978,two tone,Metalic Rootbeer & gold
1975 L48 4 speed
Success ! Yes, the headlight hoses were inverted (pre existing
), but we had to pull out the dash and console to ID and correct everything and replacing those is no walk in the park
. More tinkering to do to get everything back right, and to think, I have this job to do on at least 2 of my cars
. Let the good times roll. Thanks for your help brothers.



Jimmy B.
Just can't wait to get on the road again.
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Yeah, but at least your cars don't have wiper doors!

Barry

in Forum: C3 General Discussion
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