Wiper door open while car is off
Thread Starter
Instructor
Joined: Nov 2019
Posts: 245
Likes: 15
Wiper door open while car is off
Hate to beat a dead horse on this subject, but not sure I saw a thread on the wiper door being open when the car is off. Let me premise with I currently have the console and gauge cluster out to work on the cables. I also have the steering column down and dash loose to work on the light switch that I thought was the issue with the headlights not raising. Before changing out the switch I switched the vacuum hoses on it and solved the headlight issue.....but at sometime the wiper door went up and now continues to stay open while the car is off.
I saw a lot of great threads on the operation of the wiper system , but thought the wiper system is vacuum activated, how can they be open with the car off?
I saw a lot of great threads on the operation of the wiper system , but thought the wiper system is vacuum activated, how can they be open with the car off?
Race Director
Joined: Apr 2011
Posts: 11,183
Likes: 3,336
From: North of Toronto - Ontario
Door should be in whatever state it was when the car was turned off (closed or open)
There is some vacuum left (or however you would say that) in the reservoir that allows it to open once or twice after the car is shut off, same as the headlights.
The door can be opened without the wipers on using the valve under the steering wheel (along with the electric switch to stop the wipers mid-wipe for changing the blades)
If the door is closed and opens on it's own when the car is shut off then there is something wrong (leaking) with the vacuum system or adjustment on the door (usually leaking)
M
There is some vacuum left (or however you would say that) in the reservoir that allows it to open once or twice after the car is shut off, same as the headlights.
The door can be opened without the wipers on using the valve under the steering wheel (along with the electric switch to stop the wipers mid-wipe for changing the blades)
If the door is closed and opens on it's own when the car is shut off then there is something wrong (leaking) with the vacuum system or adjustment on the door (usually leaking)
M
Safety Car
Joined: Apr 2006
Posts: 4,057
Likes: 421
From: BC
Mooser is correct. If you leave the wiper door open it will remain open after all vacuum is gone. It requires vacuum to both signal movement and provide movement. If the door is closed on shutdown and goes up after, then you have a problem but if you leave it open it should remain open. Same as the headlights.
2nd Gear
Joined: Aug 2008
Posts: 2
Likes: 3
I recently had this problem on my 1970. I checked for vacuum leaks on the relay, actuator, and check valve. I found some issues there and corrected them but still had the same issue. So I checked for vacuum leaks from any hoses related to the wiper system and found no issues. Then I checked for vacuum leak in the reservoir by running a short piece of tubing between two of the vacuum nipples and hooked the mityvac to the third nipple. This isolates the tank. Lucky me, no vacuum. Just to confirm there was an issue with the reservoir, I left the short piece of tubing on two of the nipples and put compressed air into the third nipple. I could hear air escaping from the tank. I removed the tank and found three cracks in the metal that weren't visible from the engine side. Once the cracks were welded, I tested the tank both under vacuum (lots of hand pumping with the mityvac) and with compressed air (do this first). If there aren't any leaks, the tank will slightly expand when pressurized with the compressed air. That solved the problem. Good luck.
