Wiper Door Issue
Thread Starter
Drifting
Joined: May 2000
Posts: 1,478
Likes: 38
From: Long Island NY
Wiper Door Issue
Having some problems with wiper lid on my 71. Doesn't close completely and at times when car is running it will raise a bit without wipers on. Also wipers don't synchronize together hitting slightly when turned off to park. Obviously a vacuumed problem together with linkage problem? Just looking for prior knowledge from members that have experience with this.
Drifting
Joined: Jul 2006
Posts: 1,259
Likes: 154
From: Deplorableville Nebraska
Most wiper door issues stem from the safety valve located under the passenger (right) side wiper arm. If your valve is original, it may be able to be rebuilt. To test, remove the wiper grill, and leave the door installed. If you have a Mityvac or equivalent, disconnect the lower 2 vacuum hoses, connect to the middle vacuum port, and block the lower port. Pump it up, and it should hold vacuum. If no Mityvac, connect a short hose to the middle port, block the lower port, and try to blow through it. You should not be able to.
There are other tests you can do, but this one is the most important one, and it will tell us much about where to possibly go next. Report back.
There are other tests you can do, but this one is the most important one, and it will tell us much about where to possibly go next. Report back.
Team Owner
Joined: Sep 2006
Posts: 31,134
Likes: 4,206
From: Westminster Maryland
Hi V,
The wiper arms can only fit on the wiper transmission shafts in one way because of the 'keyway' that's part of the shaft and arm base.
Problems with the wipers hitting are often caused either by improper refills or blades being installed or the wiper 'sweep' not being adjusted properly.
There is a screw on each arm that adjusts the angle of the end of the arm/blade. This adjustment often helps with blades that sweep too far or hit at the center.
There is also some 'linkage' adjustment for sequencing the arms at the center of the linkage near the wiper motor.
Maybe?
Regards,
Alan
The 'key' on the transmission shaft.
The 'keyway' in the arm.
Screw 'A' and how it adjusts the end of the arm's angle.
The linkage adjustment at the wiper motor.
The wiper arms can only fit on the wiper transmission shafts in one way because of the 'keyway' that's part of the shaft and arm base.
Problems with the wipers hitting are often caused either by improper refills or blades being installed or the wiper 'sweep' not being adjusted properly.
There is a screw on each arm that adjusts the angle of the end of the arm/blade. This adjustment often helps with blades that sweep too far or hit at the center.
There is also some 'linkage' adjustment for sequencing the arms at the center of the linkage near the wiper motor.
Maybe?
Regards,
Alan
The 'key' on the transmission shaft.
The 'keyway' in the arm.
Screw 'A' and how it adjusts the end of the arm's angle.
The linkage adjustment at the wiper motor.
Thread Starter
Drifting
Joined: May 2000
Posts: 1,478
Likes: 38
From: Long Island NY
Ok. Thanks for all useful info as always on this forum. I've got the wiper door working as it should. Finally snapping shut. Changed vacuum line check valve and filter. Both were leaking. But.....wipers are not parking completely causing door to close on them. Actually only passenger side top wiper getting nipped. I've tried the adjust screw under wiper as pic above shows but still not parking fully.
Team Owner
Joined: Sep 2006
Posts: 31,134
Likes: 4,206
From: Westminster Maryland
Hi V,
I believe you need to adjust the 2 bolts that position the wiper interlock switch on it's bracket so that the lever that closes the plunger on the switch is further down before the switch signals the door to close.
There should be enough adjustment to do that…. if not you'll need to adjust the wiper transmission arms at the center so the lever pushes the switch when the arms are further down.
Regards,
Alan
Switch adjustment.
Right side wiper transmission arm adjustment.
I believe you need to adjust the 2 bolts that position the wiper interlock switch on it's bracket so that the lever that closes the plunger on the switch is further down before the switch signals the door to close.
There should be enough adjustment to do that…. if not you'll need to adjust the wiper transmission arms at the center so the lever pushes the switch when the arms are further down.
Regards,
Alan
Switch adjustment.
Right side wiper transmission arm adjustment.
Last edited by Alan 71; Oct 28, 2015 at 03:12 PM.
Team Owner
Joined: Sep 2006
Posts: 31,134
Likes: 4,206
From: Westminster Maryland
Hi V,
Are you sure that it's the correct wiper arm, it's not bent, the arm is fully seated on the transmission… did you feel the 'prong 'click'?, and is it the proper blade holder and blade?
Regards,
Alan
Are you sure that it's the correct wiper arm, it's not bent, the arm is fully seated on the transmission… did you feel the 'prong 'click'?, and is it the proper blade holder and blade?
Regards,
Alan
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Thread Starter
Drifting
Joined: May 2000
Posts: 1,478
Likes: 38
From: Long Island NY
Alan. Looking and comparing your pics with my linkage and wiper arms all look to be same. Blades look to be correct also. Possibility with bent arm. Let u know when I make further adjustments. Thanks.
