68 wiper door last question
Thread Starter
Pro
Joined: Oct 2009
Posts: 604
Likes: 14
From: Harleysville Pa
68 wiper door last question
OK thanks for all the help with my questions. Almost all is working as it should. One remaining problem. The door does not seem to have enough vacuum to close. It opens well, and the wipers work as they should. When we turn them off they go to park correctly but the door will not close. Any ideas on how to fix?
Thanks
Ernie
Thanks
Ernie
Team Owner
Joined: Sep 2006
Posts: 31,266
Likes: 4,355
From: Westminster Maryland
Hi Ernie,
Several things need to happen for the door to close.
The wiper switch must be turned to off so the wipers must move to the 'park' position.
This causes the plunger on the safety valve below the wiper arm to be 'depressed'.
This completes the vacuum signal to the wiper relay which then sends the vacuum signal to the 'close' side of the wiper door actuator….
which closes the door.
You need to test the relay to see if it's getting the signal to close the door and then sends the vacuum to the 'close' side (red) of the actuator.
Is that signal making it to the actuator?
Regards,
Alan
Several things need to happen for the door to close.
The wiper switch must be turned to off so the wipers must move to the 'park' position.
This causes the plunger on the safety valve below the wiper arm to be 'depressed'.
This completes the vacuum signal to the wiper relay which then sends the vacuum signal to the 'close' side of the wiper door actuator….
which closes the door.
You need to test the relay to see if it's getting the signal to close the door and then sends the vacuum to the 'close' side (red) of the actuator.
Is that signal making it to the actuator?
Regards,
Alan
Last edited by Alan 71; Jun 8, 2017 at 01:57 PM.
Former Vendor
Joined: Aug 2006
Posts: 76,656
Likes: 1,852
From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
Wow... from one Ernie to another.. 
68 Didn't use the plunger valve below the wiper arm, it was added to the 1969 production and stayed until the end.
The 1968 motor worked a bit differently than the 1969-1972 system.
My guess is there is an issue with the limit switch plunger on the firewall. When the plunger is pushed all the way in it will cut voltage to the motor. If the plunger is not pushing the switch all the way this would leave 12 volts on the brown wire that only has power when the motor is active and thus keeping the vacuum blocked to the wiper door tach solenoid.... and leaving the door open.
Willcox (Ernie)
68 Didn't use the plunger valve below the wiper arm, it was added to the 1969 production and stayed until the end.
The 1968 motor worked a bit differently than the 1969-1972 system.
My guess is there is an issue with the limit switch plunger on the firewall. When the plunger is pushed all the way in it will cut voltage to the motor. If the plunger is not pushing the switch all the way this would leave 12 volts on the brown wire that only has power when the motor is active and thus keeping the vacuum blocked to the wiper door tach solenoid.... and leaving the door open.
Willcox (Ernie)
Last edited by Willcox Corvette; Jun 8, 2017 at 04:16 PM.
Thread Starter
Pro
Joined: Oct 2009
Posts: 604
Likes: 14
From: Harleysville Pa
68 wiper door
Thanks to all. This has been very frustrating, but with all the help thru this forum and another friend everything is now working as I should. Thanks again.
Ernie
Ernie
Last edited by carlisle61; Jun 9, 2017 at 05:45 AM.
Team Owner
Joined: Sep 2006
Posts: 31,266
Likes: 4,355
From: Westminster Maryland
Hi Ernie (W!!!),
Thanks for the info about the safety valve.
I think I knew that about 68 cars but had forgotten it. I need to write it on my hand to remind me!
Was there another way to prevent the wiper door from closing on the wiper arms before they had reached the 'park' position?
Regards,
Alan
Thanks for the info about the safety valve.
I think I knew that about 68 cars but had forgotten it. I need to write it on my hand to remind me!
Was there another way to prevent the wiper door from closing on the wiper arms before they had reached the 'park' position?
Regards,
Alan
Last edited by Alan 71; Jun 9, 2017 at 06:54 AM.
Thread Starter
Pro
Joined: Oct 2009
Posts: 604
Likes: 14
From: Harleysville Pa
68 wiper door overide light
One more question on this subject. There is a light that goes on with the wiper door . Where does that plug in?
Thanks
Ernie
Thanks
Ernie
Last edited by carlisle61; Jun 9, 2017 at 10:01 AM.
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Team Owner
Joined: Sep 2006
Posts: 31,266
Likes: 4,355
From: Westminster Maryland
Hi c61,
If you look at the electrical schematic Willcox posted you'll see a note 'A' in the upper right corner.
It indicates the wire from the warning lamp in the dash runs to the wiper override switch bracket below the steering column.
It's 'hinted at' but not very clearly shown in the 68 AIM.
Regards,
Alan
If you look at the electrical schematic Willcox posted you'll see a note 'A' in the upper right corner.
It indicates the wire from the warning lamp in the dash runs to the wiper override switch bracket below the steering column.
It's 'hinted at' but not very clearly shown in the 68 AIM.
Regards,
Alan
Last edited by Alan 71; Jun 9, 2017 at 10:49 AM.
Former Vendor
Joined: Aug 2006
Posts: 76,656
Likes: 1,852
From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
Hi Ernie (W!!!),
Thanks for the info about the safety valve.
I think I knew that about 68 cars but had forgotten it. I need to write it on my hand to remind me!
Was there another way to prevent the wiper door from closing on the wiper arms before they had reached the 'park' position?
Regards,
Alan
Thanks for the info about the safety valve.
I think I knew that about 68 cars but had forgotten it. I need to write it on my hand to remind me!
Was there another way to prevent the wiper door from closing on the wiper arms before they had reached the 'park' position?
Regards,
Alan
