Sixty9

When I turn on the wipers, the door lifts a little on its own and I lift it w/my hand the rest of the way--have to and yes sux. I've sprayed WD40 on every moveable hinge from the door I can see--helped a little, but did not solve. Is there some enclosed hinge or piston that needs WD40 that I can't see anywhere? Also, when I turn them off, the door closes on the wiper every time and I have to tuck the wiper in there and push it the rest of the way down--that sux too! But right now I'll settle for gettin' the door to open on its own--even though I don't drive it in the rain--come on, you know you want everything on your car to work too! Thanx :D

TNT

A very simple fix. First the actuator rod boot seal is bad. Pull the dust cover back and inspect the seal. It's the canister on the firewall that lifts and lowers the door. Next it sounds like the vacumn switch that mounts in the wiper trough area is bad. It has a plunger that the rite wiper arm presses down on. This part is still avaliable from GM. Hope this helps. Thad

69Rat

You might want to check the vacuum canister, and make sure you don't have a vac leak. I did that to mine and found it by spraying a stream of soapy water around the vac hoses. I also had a similar problem witht e wiper door hitting the wipers as it closed too fast. I found a crack in one of the vac hoses that connects to the clothes safty switch.

Just some ideas. :cheers:

Diode

Do you have a hand vacuum pump to help trouble shoot the problem? You need to connect it directly to the "can" and see if you can get it to work that way. The diphragm might be shot. Will it open if you pull down the "service" switch under the dash? Vacuum leaks...bad switch...bad hose(s)?

Sixty9

Thanx for all the ideas and troubleshooting help--I'll scope all those areas out. Diode--no, I don't have those tools--pump, etc...Another vacuum problem I have is the light switch. I've always had to use the service switch to raise the lights--the light switch just turns the lights on--whats up w/that? :confused:

Diode

Most often it's the light switch itself, but again, it could just be a popped off or badly leaking hose to/from the switch. At least since the service switch works you know it's not the expensive stuff like headlight actuators. A hand vacuum pump is well worth the money (~$35-$40) for finding and fixing problems on a Corvette. Every damn thing on the car is vacuum operated! You can save a ton of money on repair costs with one of the pumps and a good diagram. I'm thinking of selling color coded diagrams of C3 vacuum systems showing all of the hoses and connections…what do you think?

69 LT1

If you have an early 69 your actuator will not have a seal, (link on bottom shows early actuator)
When you test your wipers you need to wet down the windshield so your wipers will go to there furthest travel points,
The passenger wiper needs to close the wiper control enough to open the port all the way, If your wiper is stopping short due to dry windshield this could cause a problem,
If your wipers stop short with a wet window theres four nuts that can be used to adjust the travel of the arms, they attatch the wiper transmission arms to the wiper motor, take the grill off and you will see them,

Headlights> start the car and build up the vacuum, shut the car off and pull the headlight switch listen by the switch for any vacuum leaks,
If theres no leaks, Pull the headlights up with your fingers (not the manual pull) start the car build the vacuum and pull the headlight switch, See if the headlights drop, if they do the hoses are backwards.
http://www.ecklers.com/product.asp?p...LU6Q0V7H1S9M28


[Modified by 69 LT1, 9:56 PM 8/4/2003]

Sixty9

Thanx again for the thoughtful responses--I will troubleshoot this tomorrow. Diode--where can I get this troubleshooting pump from and yes go for it on the diagrams---I sure forum members will ****** them up. :D

Diode

The pump I have is brand name "Mightyvac" and it came with a gauge and a bunch of hoses and adapters and even a sealed cup to use it for bleeding brakes. I got it from a SnapOn tool truck, but they're pretty popular and available in most auto parts stores. Since it has the gauge, you can use it to measure vacuum at various points with the engine running, or pump the line down by hand and see if the questionable actuator or diaphragm is working as well as watch the gauge to see if there is a leak.