Wiper Door Vacuum
Thread Starter
Instructor
Joined: Mar 2013
Posts: 103
Likes: 3
From: Pittsburgh PA
Wiper Door Vacuum
Hi I printed out a few vacuum posts and will research more on the forum so I apologize if this is a duplicate. I am just trying to solve my problem quickly.
My 72 wiper door only opens when you pull the override lever. All other vacuum works lights are fine etc. The door opens fine with the over ride and the wipers work fine. I tried replacing the switch behind the tach and that did not resolve the issue.
Any help or advice on what to check next would be appreciated.
My 72 wiper door only opens when you pull the override lever. All other vacuum works lights are fine etc. The door opens fine with the over ride and the wipers work fine. I tried replacing the switch behind the tach and that did not resolve the issue.
Any help or advice on what to check next would be appreciated.
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Did you look at Willcox's site for the trouble shooting guide?
Thread Starter
Instructor
Joined: Mar 2013
Posts: 103
Likes: 3
From: Pittsburgh PA
I ordered that guide and it should be here this week. I am thinking either the switch on the tach isn’t getting juice or maybe I got a leak from the switch to the override? We shall see.
Pro
Joined: Apr 2012
Posts: 657
Likes: 114
From: Picton NSW
OK that is strange, something is connected incorrectly , but that is obvious .
I have the dash out if my 70 model, I'll refresh my mind on where the pilots lines run. Ill be back to you,
one other thing,when you turn the wipers on does the door lift up, or does that happen when you pull the over ride down,
Bfit
I have the dash out if my 70 model, I'll refresh my mind on where the pilots lines run. Ill be back to you,
one other thing,when you turn the wipers on does the door lift up, or does that happen when you pull the over ride down,
Bfit
Last edited by bfit; Aug 7, 2018 at 12:23 AM.
Thread Starter
Instructor
Joined: Mar 2013
Posts: 103
Likes: 3
From: Pittsburgh PA
Thank you. I will be pulling my dash as soon as I make room in the garage for the car to sit apart for a few days. I also need to replace a speaker and the ac duct that goes under the steering wheel was missing when I bought the car.
I am am wondering if my issue could be as simple as the actuator on the back of the tach not getting power when the wiper switch is pushed. I did not think to test that when I had it apart last time.
I am am wondering if my issue could be as simple as the actuator on the back of the tach not getting power when the wiper switch is pushed. I did not think to test that when I had it apart last time.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Did you connect the solenoid switch (behind tach) correctly? The port sticking out the end of the switch is a VENT and should not have anything connected to it. If you connected a vacuum hose to that [end] fitting, that's why it isn't working.
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Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
You can check that switch by connecting 12 vdc to the wiring and attempting to blow or suck through the vacuum hose connections. Turning the unit ON/OFF should allow air to pass or to not allow air to pass. For a function check with it in the car, turn ignition to ON (engine not started) and turn ON/OFF the wiper switch while trying to blow thru the vacuum line connected to it. If the test fails, the problem could be that no power is getting to the switch (check with voltmeter) via the wiper switch OR the new solenoid switch is defective (it happens!).
If that testing is successful and you still can't open the wiper door, you may not have vacuum getting to that solenoid switch OR the safety switch under the right side wiper is the problem (either with its positioning or being faulty). As mentioned above, check out the diagnostic info and vacuum circuit on Willcox site.
If that testing is successful and you still can't open the wiper door, you may not have vacuum getting to that solenoid switch OR the safety switch under the right side wiper is the problem (either with its positioning or being faulty). As mentioned above, check out the diagnostic info and vacuum circuit on Willcox site.