windshield wiper motor synch
nitro25
09-23-2008, 09:19 PM
on the 2000 pontiac montana, does anyone know how to synch the wiper motor and wiper motor crank arm. I took it off accidentally while doing the struts and now i cant get my wipers to park correctly and when i put on intermittent they pause vertically instead of horizontally. Also on the back of the crank arm is a small lever thing that i am not sure where to put...Any help would be greatly appreciated!!!
1999montana
09-29-2008, 07:37 PM
Welcome the the Forum, a place where you can find a solution for just about anything the needs fixing on these vans.
Here's what I did to get the motor and arms back in synch.
Remove the screw in the top of the eccentric on top of the motor shaft and remove the eccentric, arm and all.
Then, turn on the wipers and let the motor go through a number of cycles before turning it off. The motor should return to the parked position.
With the wiper arms down at the cowl (nearest the hood), re-attach the eccentric and re-insert the screw and tighten down securely.
Have someone turn the wipers on, but be ready to turn the wipers off at the ignition key, not the switch if something doesn't look, act or sound right.
If all goes well, the wipers should go through their cycle and at least attempt to park. If they don't park, but stop at the 'A' pillar examine what is happening with the eccentric when the motor attempts to park.
How do I know when the motor is attempting to park you say?
The motor will cycle, and then momentarily go into reverse. This is important. When the motor goes into reverse a small metal spring on the bottom of the eccentric will connect with a stationary post on the wiper assembly. This causes the eccentric to go off center, causing the wiper arms to park at the cowl. When the motor is in run mode, the eccentric is centered.
If you observe that the mechanism is not parking properly, you can take it apart and clean, grease and oil it by removing the screw on top and disconnecting the eccentric and rod it is attached to. I used brake cleaner on mine and even carefully removed the one-way clip that holds the eccentric assembly together so I could clean inside as well.
Once everything was clean, I used a film of high temperature wheel bearing grease to lubricate the inner and outer parts and then followed that with 10w30 motor oil once the eccentric was re-assembled and the one-way clip was adjusted for a tight fit, then pressed back on with a 6-point socket and a vise as a press.
Hope this helps.
Here's what I did to get the motor and arms back in synch.
Remove the screw in the top of the eccentric on top of the motor shaft and remove the eccentric, arm and all.
Then, turn on the wipers and let the motor go through a number of cycles before turning it off. The motor should return to the parked position.
With the wiper arms down at the cowl (nearest the hood), re-attach the eccentric and re-insert the screw and tighten down securely.
Have someone turn the wipers on, but be ready to turn the wipers off at the ignition key, not the switch if something doesn't look, act or sound right.
If all goes well, the wipers should go through their cycle and at least attempt to park. If they don't park, but stop at the 'A' pillar examine what is happening with the eccentric when the motor attempts to park.
How do I know when the motor is attempting to park you say?
The motor will cycle, and then momentarily go into reverse. This is important. When the motor goes into reverse a small metal spring on the bottom of the eccentric will connect with a stationary post on the wiper assembly. This causes the eccentric to go off center, causing the wiper arms to park at the cowl. When the motor is in run mode, the eccentric is centered.
If you observe that the mechanism is not parking properly, you can take it apart and clean, grease and oil it by removing the screw on top and disconnecting the eccentric and rod it is attached to. I used brake cleaner on mine and even carefully removed the one-way clip that holds the eccentric assembly together so I could clean inside as well.
Once everything was clean, I used a film of high temperature wheel bearing grease to lubricate the inner and outer parts and then followed that with 10w30 motor oil once the eccentric was re-assembled and the one-way clip was adjusted for a tight fit, then pressed back on with a 6-point socket and a vise as a press.
Hope this helps.
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