Malfunctioning headlights and/or wiper doors are very common on 1968-1982 Corvettes. Though the system may seem to be very complicated at first glance, it is actually very simple and can be troubleshooted by any “do-it-yourselfer” with basic hand tools and one free afternoon. Usually dry or cracked vacuum hoses and actuator seals are your culprits. If they are original, they have experienced a great deal of heat from the engine over many years. Would you like more information on how to replace your Corvette’s old actuator seals? Read our technical article: “1968-1982 Corvette Headlight Repair“ at Corvette Magazine.com.
To get started read through a 1968-1982 Corvette Vacuum System Troubleshooting Guide that comes with illustrated diagrams and information necessary to diagnose your Corvette’s Vacuum System. The troubleshooting guide goes into great detail about the vacuum system and will eliminate just about any frustration brought on by malfunctioning wiper doors and headlights.
If you get into your Corvette’s Vacuum System Overhaul and have replaced all hoses, valves, seals, etc. and still have issues with the headlights or wiper door not working properly you may have a problem within your Corvette’s vacuum control subsystem. The troubleshooting guide will go into more detail about the control subsystem and operating subsystem, which will help you gain a better understanding of your entire Corvette’s vacuum system. After reading the vacuum troubleshooting guide you will be able to accurately diagnose any problems with your Corvette’s headlight or wiper door vacuum system.
There are six different Corvette vacuum system configurations for 1968-1982 Corvettes. Zip has all six broken down into easy to read diagrams with installation instructions. These come with every overhaul kit we sell, but you can also click below to download the vacuum system diagram you need for free.
|
|
|
|
|---|---|---|
|
|
|
|
Zip’s Corvette Vacuum System Overhaul Kit is great to have while repairing your Corvette’s vacuum system because it includes all components needed to fix the most common vacuum problems. Each kit includes color striped vacuum hoses, a replacement vacuum check valve, vacuum filter, a pair of replacement actuator front seals, wiper canister seal (’70-72 only), and a 1968-1982 Corvette Vacuum System Troubleshooting Guide.
Keep your Corvette’s vacuum system original and buy a complete kit from Zip Corvette with easy to read, accurate diagrams and instructions.
How can I trace down all components to the alarm on my 1976 Corvette? It does not work and I would like to find out why. Any help would be appreciated dearly.
Thanks
Carnie
Carnie,
A 1976 Corvette Assembly Manual will show you all of the components dealing with your Corvette’s alarm system. The assembly manual does not include instructions on repairing or replacing any parts, it just includes diagrams.
Do you have any information on how to detect bad relays for 1968-1982 Corvette head light vacuum?
Mickey,
The 1968-1982 Corvette Vacuum System Troubleshooting Guide is the simplest way to diagnose and fix Corvette vacuum system problems.
I have a 1971 Corvette with some wiper door issues. The wiper system did not operate at all when I first started. I have purchased all of the vacuum line kits, put on new actuators, wiper motor, switch, etc and replaced nearly all the components. My issue is when I start the car, the wiper door comes up. The manual over ride does not effect it either way. When I turn the wiper switch on, the door closes. I obviously have something wrong. I have traced all my vacuum lines and all are in the correct positions according to the assembly manual and the vacuum hose instruction sheet. Any ideas?
Ronnie,
Something is dumping vacuum. You either have a line hooked up backwards or a valve that is bad. Look at the electrical vacuum switch on the back of the tachometer, they are usually the culprit. The system is pretty straight forward as it dumps vacuum to open the door. The first thing to do is to go back over the lines, if you are sure they are hooked up correctly then find someone who has an EVAP smoker. You can hook this up to your vacuum line under the hood and find every leak in the system.
I am restoring a 1969 Corvette big block, 454 with a heavy cam. Thanks for sharing the diagram for the vacuum hose kit which I will soon order. I have two questions on the diagram. First, hose 11, Wiper Arm Vent Hose does not appear to connect from the Wiper Activator Relay to anything, true? Secondly, the Wiper Door Solenoid has two outlets other than the primary line. One connects to the override switch, the diagram does not indicate where the second outlet connects? I do not want to miss anything when I order parts, so your help is appreciated!
Paul,
The lines you are asking about are vents. The wiper relay is under the dash. It should have a filter over it and it is also a vent.
When I try to download a diagram, it trys to download other programs. Why?
Darrow:
You need to have some type of .pdf viewer installed on your computer to view the diagrams. Most people use Adobe Reader. Here is a link to install: http://get.adobe.com/reader/
The Adobe Reader software is free.
I have a 1971 and it has been determined that the vacuum canister will not hold a vacuum. I checked Ecklers and could not find a canister for 1971. Do you know of any sources?
Joe:
This part can only be found used. There is no current reproduction.
Hi ~ I have a 1968 Corvette Convertible..the problem we’re having is the transmission (Auto) will not engage into other gears..we have checked fluid level & it’s full. Any ideas? Someone has mentioned it may be a vacuum issue. Thanks for any help.
Deanne:
There is also a mechanical servo in the back. It sounds as though it is time for a rebuild.