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Discussion Starter · #1 ·
I really suspect this is a mechanical issue, but I thought I'd throw it out to the experts anyway.

My wipers seem to work fine in low speed. When I put the switch on high they seem to start off fine, but within less than 1 revolution the arms slow almost to a stop and begin moving in short little jumps. If I switch back to low, the blades slow even further and continue the jumping motion. When I try to restart them in low speed they sometimes still only move in little jumps until I get out and manually "assist" them through a few revolutions. After doing this though they don't always park properly. I can usually force them back to park to line them back up and they work ok in low again.

I suspect the nylon gear is worn although when I disassembled the gear drive mechanism the teeth looked ok.



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Rod

67 396
SS clone

Daddy's Red Car
 

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Does the wiper transmission move freely? I had the pivot area below one of the wiper blades freeze up and bind up. Motor wasn't strong enough to drive the transmission. It sort of acted like that.
 

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Discussion Starter · #3 ·
If I move the arms by hand with the motor disconnected it doesn't seem to have any restrictions. Low speed seems to work fine and high speed initially seems fine but before the first stroke is complete the arms start jumping and it sounds like there is binding in the motor gearbox. The nylon gear looks alright, maybe there is some lateral movement which allows the gear to start slipping teeth? I looked at the bronze bushings the and couldn't see excess wear, but I don't have a mic small enough to verify clearances. Doesn't seem to be any slop though with the box reassembled however it still slips.

I wondered if there could be an alignment problem with the wiper transmission since the "park" position seems to move once the arms start to jump.

I tried turning on the switch with the linkage disconnected and then turning it off to allow the motor to park before I reattached the linkage, that should have prevented any alignment problems but didn't seem to help.

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Rod

67 396
SS clone

Daddy's Red Car



[This message has been edited by rthlc (edited 05-26-2002).]
 

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Sorry
I can't offer much more help. Last time I had a motor problem I just picked up a rebuilt through Kragen.
 

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Did you try to adjust the set screw at the top of the long armature that has the gear on it from the motor. It drives the big round nylon gear. sounds like your armature is moving to the side a bit and the teeth are jumping. I was told to loosen the nut and tighten the set screw enough to put tension on the armature. That keeps the whole gear set steady, and prevents the switch from rockin in and out of park. Worth a try I guess. The set screw in on my 70, I assume 67 is similar.
 

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Discussion Starter · #6 ·
The motor on mine is the rectangular style, I'll take it apart again and post my findings.. As I said it seems like the gear is slipping even though it doesn't appear to have excess wear, so this your explanation sounds very plausible.

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Rod

67 396
SS clone

Daddy's Red Car
 

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Discussion Starter · #7 ·
I finaly managed to get back to the wiper motor problem, after disassembling the motor once more I think the problem is worn pilot bearings causing too much lateral movement, so it looks like time for a rebuilt motor.

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Rod

67 396
SS clone

Daddy's Red Car
 
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