So Close--Wiper Door Question
Thread Starter
Drifting
Joined: Jun 2006
Posts: 1,327
Likes: 43
From: Vernon CT
So Close--Wiper Door Question
OK, so my 71 LS5 is close to the complete vacuum system working.
Lights pop up quickly and go down as they should.
Wipers work and park correctly.
However the wiper door opens on startup and does not go down. (i think in the distant pass it would go up then go down after a minute on startup..?)
Anyway it goes up and stays up, it won't go down until the car is shutoff and I have to manually ease it down. (Cabin over-ride is NOT pulled down)
I last year removed the Wiper Door Vacuum Control Solenoid and cleaned it out, it was plugged. The door worked for a short while , then stopped working again.
Theres no vacuum at the door actuator. I have to be close...
Lights pop up quickly and go down as they should.
Wipers work and park correctly.
However the wiper door opens on startup and does not go down. (i think in the distant pass it would go up then go down after a minute on startup..?)
Anyway it goes up and stays up, it won't go down until the car is shutoff and I have to manually ease it down. (Cabin over-ride is NOT pulled down)
I last year removed the Wiper Door Vacuum Control Solenoid and cleaned it out, it was plugged. The door worked for a short while , then stopped working again.
Theres no vacuum at the door actuator. I have to be close...
Drifting
Joined: Nov 2016
Posts: 1,957
Likes: 576
From: Pittsburgh PA
I had the exact same problem with my 68.
unfortunately I have no idea what i did to fix it!
Seriously though, I was trying to troubleshoot my system and I pulled the lines off the vacuum canister for the door and then bam all of the sudden it started working
one thing I did read is that the wiper door staying open is a safety feature. when the system has low vacuum, the door defaults to open to ensure you can use your wipers. so maybe there is a leak somewhere?
unfortunately I have no idea what i did to fix it!
Seriously though, I was trying to troubleshoot my system and I pulled the lines off the vacuum canister for the door and then bam all of the sudden it started working
one thing I did read is that the wiper door staying open is a safety feature. when the system has low vacuum, the door defaults to open to ensure you can use your wipers. so maybe there is a leak somewhere?
Safety Car
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Sounds like the small leak became a big one.
You could maintain external vac via a miti vac on the control line,
small black line on top of relay.
Start the car and see if the door closes.
Most likely the relay. (Drivers Side Firewall)
Try it and post your results.
Marshal
You could maintain external vac via a miti vac on the control line,
small black line on top of relay.
Start the car and see if the door closes.
Most likely the relay. (Drivers Side Firewall)
Try it and post your results.
Marshal
Last edited by marshal135; Apr 11, 2017 at 04:43 PM.
Drifting
Joined: Aug 1999
Posts: 1,451
Likes: 84
From: Round Rock TX
I have been dealing with same issue. When start the car the door opens, if not already, and doesn't go down. I had a hole in the red hose the goes from the wiper valley to the override switch. It also seems the "new" wiper valley switch also has failed.
In short term, I plugged the white and red hose together in wiper valley with a coupler. After doing this the door opens and closes with the wiper switch. The timing is off and the door will close on the wiper arm.
The valve by the master cylinder on the firewall controls the door. If the top hose has vacuum the door will close, if not it will open. Ensure the hose on front of the actuator also isn't leaking. If not leaking at actuator (front plug must be in place as well) put vacuum to the canister on firewall by the master cylinder. If closes the issue seems to be either the wiper valley, if join together and works, or the hose to inside the car.
In short term, I plugged the white and red hose together in wiper valley with a coupler. After doing this the door opens and closes with the wiper switch. The timing is off and the door will close on the wiper arm.
The valve by the master cylinder on the firewall controls the door. If the top hose has vacuum the door will close, if not it will open. Ensure the hose on front of the actuator also isn't leaking. If not leaking at actuator (front plug must be in place as well) put vacuum to the canister on firewall by the master cylinder. If closes the issue seems to be either the wiper valley, if join together and works, or the hose to inside the car.
Team Owner
Joined: Sep 2006
Posts: 31,213
Likes: 4,301
From: Westminster Maryland
Hi 72/86
The wiper door actuator is controlled by the vacuum relay mounted behind the right side wheel well.
There is a small hose that controls the relay's function and 3 large hoses…
one that is the vacuum supply for the relay, often yellow striped,
a large green striped hose that supplies the vacuum to the actuator to open the wiper door,
and a large red hose that supplies the vacuum to the actuator to close the door.
Have you checked the hose routing to the relay and from the relay to the actuator, and the functions of the relay?
Once you get the door opening and closing you can then attend to have it opening in time for the wipers to start and waiting to close until the wipers have parked.
Check the hoses and relay.
Regards,
Alan
The wiper door actuator is controlled by the vacuum relay mounted behind the right side wheel well.
There is a small hose that controls the relay's function and 3 large hoses…
one that is the vacuum supply for the relay, often yellow striped,
a large green striped hose that supplies the vacuum to the actuator to open the wiper door,
and a large red hose that supplies the vacuum to the actuator to close the door.
Have you checked the hose routing to the relay and from the relay to the actuator, and the functions of the relay?
Once you get the door opening and closing you can then attend to have it opening in time for the wipers to start and waiting to close until the wipers have parked.
Check the hoses and relay.
Regards,
Alan
Last edited by Alan 71; Apr 11, 2017 at 04:51 PM.
Drifting
Joined: Jul 2006
Posts: 1,259
Likes: 154
From: Deplorableville Nebraska
However the wiper door opens on startup and does not go down. Anyway it goes up and stays up, it won't go down until the car is shutoff and I have to manually ease it down.
The trick is to find the reason the control chamber is NOT getting vacuum. The most common issue in this situation is the wiper arm safety valve. When original ones get old, they leak and fail. When new Chinese copies are purchased, they fail right out of the box most of the time as Mr Duntov found out.
If your solenoid is passing vacuum through it now, the next component in line is the override switch. These rarely fail! The next component is the wiper arm switch. A simple test will verify it's condition. Bypass the switch by connecting the two lower hoses together that connect to it (red & white if you look at color). You should now have vacuum to the relay on startup.
This is a simple test. Just remove the wiper grill (not the door). If you do indeed need a new wiper arm safety valve, Willcox sells one that is guaranteed to actually work...........
Thread Starter
Drifting
Joined: Jun 2006
Posts: 1,327
Likes: 43
From: Vernon CT
I had the exact same problem with my 68.
unfortunately I have no idea what i did to fix it!
Seriously though, I was trying to troubleshoot my system and I pulled the lines off the vacuum canister for the door and then bam all of the sudden it started working
one thing I did read is that the wiper door staying open is a safety feature. when the system has low vacuum, the door defaults to open to ensure you can use your wipers. so maybe there is a leak somewhere?
unfortunately I have no idea what i did to fix it!
Seriously though, I was trying to troubleshoot my system and I pulled the lines off the vacuum canister for the door and then bam all of the sudden it started working
one thing I did read is that the wiper door staying open is a safety feature. when the system has low vacuum, the door defaults to open to ensure you can use your wipers. so maybe there is a leak somewhere?
Thread Starter
Drifting
Joined: Jun 2006
Posts: 1,327
Likes: 43
From: Vernon CT
Hi 72/86
The wiper door actuator is controlled by the vacuum relay mounted behind the right side wheel well.
There is a small hose that controls the relay's function and 3 large hoses…
one that is the vacuum supply for the relay, often yellow striped,
a large green striped hose that supplies the vacuum to the actuator to open the wiper door,
and a large red hose that supplies the vacuum to the actuator to close the door.
Have you checked the hose routing to the relay and from the relay to the actuator, and the functions of the relay?
Once you get the door opening and closing you can then attend to have it opening in time for the wipers to start and waiting to close until the wipers have parked.
Check the hoses and relay.
Regards,
Alan
The wiper door actuator is controlled by the vacuum relay mounted behind the right side wheel well.
There is a small hose that controls the relay's function and 3 large hoses…
one that is the vacuum supply for the relay, often yellow striped,
a large green striped hose that supplies the vacuum to the actuator to open the wiper door,
and a large red hose that supplies the vacuum to the actuator to close the door.
Have you checked the hose routing to the relay and from the relay to the actuator, and the functions of the relay?
Once you get the door opening and closing you can then attend to have it opening in time for the wipers to start and waiting to close until the wipers have parked.
Check the hoses and relay.
Regards,
Alan
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Thread Starter
Drifting
Joined: Jun 2006
Posts: 1,327
Likes: 43
From: Vernon CT
Im consulting a Wilcox diagram found in another post however the parts arenot labeled.
Team Owner
Joined: Sep 2006
Posts: 31,213
Likes: 4,301
From: Westminster Maryland
Hi,
Test:
With the plunger pushed in (retracted): the unmarked port should hold vacuum, while the red and white ports are open.
With the plunger out (extended): the port marked white should hold vacuum. The unmarked and red ports should be open.
The red port should remain open regardless of the position of the plunger (extended or retracted).
Check that the plunger return spring is functioning properly and consistently.
Ensure that the ribbed seal is intact and seats in the grooves on the plunger and switch's body.
Regards,
Alan
Test:
With the plunger pushed in (retracted): the unmarked port should hold vacuum, while the red and white ports are open.
With the plunger out (extended): the port marked white should hold vacuum. The unmarked and red ports should be open.
The red port should remain open regardless of the position of the plunger (extended or retracted).
Check that the plunger return spring is functioning properly and consistently.
Ensure that the ribbed seal is intact and seats in the grooves on the plunger and switch's body.
Regards,
Alan
Thread Starter
Drifting
Joined: Jun 2006
Posts: 1,327
Likes: 43
From: Vernon CT
Team Owner
Joined: Sep 2006
Posts: 31,213
Likes: 4,301
From: Westminster Maryland
Hi 72/86,
No it doesn't.
Well, the rubber 'bellows' comes off, but nothing else.
UNLESS you're Dave, and are able to repair it!!!!!!
I know he's reproducing them... I'm not sure if he's repairing originals?
Regards,
Alan
No it doesn't.
Well, the rubber 'bellows' comes off, but nothing else.
UNLESS you're Dave, and are able to repair it!!!!!!
I know he's reproducing them... I'm not sure if he's repairing originals?
Regards,
Alan
Last edited by Alan 71; Apr 12, 2017 at 11:02 AM.
Thread Starter
Drifting
Joined: Jun 2006
Posts: 1,327
Likes: 43
From: Vernon CT
Now I do have a JB Industries DV-6E 6 CFM Eliminator Economy Vacuum Pump C1. Can I use it instead of running the engine?
I still have a 1969 that none of the vacuum system works so the pump would come in handy.
Team Owner
Joined: Sep 2006
Posts: 31,213
Likes: 4,301
From: Westminster Maryland
Hi 72/86,
I don't know if you can use that pump.
It looks like it might be good for running/testing the entire system.
The mity-vac type pump is handy for testing the components' functions because it has a vacuum gauge too.
You can establish a vacuum on a specific component and then watch how long the vacuum is held, and if it leaks, how quickly the vacuum is lost.
Regards,
Alan
I don't know if you can use that pump.
It looks like it might be good for running/testing the entire system.
The mity-vac type pump is handy for testing the components' functions because it has a vacuum gauge too.
You can establish a vacuum on a specific component and then watch how long the vacuum is held, and if it leaks, how quickly the vacuum is lost.
Regards,
Alan
Last edited by Alan 71; Apr 12, 2017 at 11:12 AM.
Thread Starter
Drifting
Joined: Jun 2006
Posts: 1,327
Likes: 43
From: Vernon CT
I removed it from the car. Im guessing this wiper arm safety valve BELLOWS holds vacuum? Well the bellows is broken off the top and bottom so Im guessing its toast? (I ordered another)
Drifting
Joined: Jul 2006
Posts: 1,259
Likes: 154
From: Deplorableville Nebraska
The bellows has absolutely nothing to do with the operation of the safety valve. The top vacuum port is simply a vent for the closed to weather chamber the bellows creates when in one piece and installed. It was GM's way of making sure weather (rain, snow) didn't get into the top of the valve.
The new valves do not come with the bellows. You really do not need it if your car is never driven in the elements very much. As you can see in my video, not needed.
The new valves do not come with the bellows. You really do not need it if your car is never driven in the elements very much. As you can see in my video, not needed.