Wiper Doors

77CVT · May 14, 2007, 01:12:35 PM

Anyone got info on how to adjust the wiper door for early C3's?

MADLT1 · May 14, 2007, 04:52:53 PM

MADLT1 · May 14, 2007, 04:56:56 PM

as you can see there are a few area's were you can adjust and shim the door out or in,also the holes on the firewall are elongated ,so you can adjust up and down,allso when you take the door off check the nylon bushes as they were.

69 DIRTY RAT · May 14, 2007, 07:16:29 PM

Go electric!

77CVT · May 15, 2007, 08:36:36 AM

;42

The door goes down when the wipers are on fast and then things get ugly from there.

I haven't had much to do with early C3's so I am sure I'll be bugging you all frequently.

69VETTE · May 15, 2007, 08:38:59 AM

QuoteOriginally posted by 77CVT
;42

The door goes down when the wipers are on fast and then things get ugly from there.

I haven't had much to do with early C3's so I am sure I'll be bugging you all frequently.

There is suppose to be a safety switch under the door near the wipers to not allow this. Maybe this swtich has dunn its nanna...;27

M;36

Chromie · May 15, 2007, 03:20:44 PM

Hi 77CVt;42

Your problem of the wiper door closing when wipers are in operation sounds like the interlock valve, which is located at the right wiper arm, assuming that all your vacuum hoses are routed correctly.;27
This interlock valve senses the position of the arm and if it thinks that your wiper arm has parked it will allow the closing of the wiper door.;50

77CVT · May 15, 2007, 04:15:41 PM

Thanks Chromie. I think I'll be replacing vacuum hoses where ever I can.

RHD.68.l89 · May 15, 2007, 05:07:03 PM

Does the door try to close immediately you switch to high? Could be the vacuum solenoid is losing it's electrical signal when you switch to high and the safety interlock (as mentioned earlier) is faulty.
A common fault is the door opening under wide open throttle as the vacuum signal disappears but there is still vacuum in the tank to operate the door. Not related to your fault but common anyway.
Congrats on the purchase!

MADLT1 · May 15, 2007, 05:57:02 PM

there is a guide called troubleshooting,the 1968-1982 headlight and windshield wiper door vacuum system.it is available at mid america and is a must for all c3 owners.the vacuum system on these cars is complex,but simplified in this guide;42

Cameron 77C3 · May 15, 2007, 07:32:05 PM

Here is the llink to what MADLT1 speaks of:-

Click This Pic

69VETTE · May 15, 2007, 09:43:17 PM

QuoteOriginally posted by RHD.68.l89

A common fault is the door opening under wide open throttle as the vacuum signal disappears but there is still vacuum in the tank to operate the door. Not related to your fault but common anyway.
Congrats on the purchase!

Yes, i remember i had this problem with my C3 because the vacumme hoses on the light switch on the console were incorrectly placed... you could also hear a suction sound when ever you turned your lights on..

Im sure its a common simple error....

Oh... Thanks Chromie for helping us out with the explaining ;42

M;36

77CVT · May 16, 2007, 12:38:45 PM

QuoteOriginally posted by RHD.68.l89
Does the door try to close immediately you switch to high? Could be the vacuum solenoid is losing it's electrical signal when you switch to high and the safety interlock (as mentioned earlier) is faulty.
A common fault is the door opening under wide open throttle as the vacuum signal disappears but there is still vacuum in the tank to operate the door. Not related to your fault but common anyway.
Congrats on the purchase!

Not sure yet. It may be a while before I hit WOT! ;-)

cosmicvette · July 09, 2007, 07:06:34 PM

Replacing all the vacuum hoses is a good place to start (I am sure they are all overdue for replacement) and follow the troubleshooting guide mentioned.

I got a vacuum hose kit from: http://www.docrebuild.com/

It was a perfect copy of the original (even had correct colours on the hoses and were shaped correctly)