[200q20v] 91 Avant rear wiper

[Peter Schulz]

At 03:01 PM 5/22/2001 -0400, you wrote:
>Finally got some rain in N.E.  Turn on the rear wiper on my 91 200 Avant,
>wiper goes half way and stops. Fuse OK. I assume the motor went bye-bye.
>Smells bad too. Haven't taken it out yet. Any experience or BTDT's.  TIA
>
>Gary
>91 200TQA
>94UrS4
>
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>200q20v at audifans.com
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Gary:

Might be similar issue that the Coupe Quattro owners experience....

The grease inside the gearbox dries into a hard substance.

Solution is to dis-assemble the wiper motor/gearbox, remove the crud. 
relube, and re-assemble.

see http://20v.org/wiper.htm#rear

HTH

Peter Schulz
1990 CQ
1991 200 20v TQW
Chelmsford, MA USA
peschulz at cisco.com



Motor:
The lubricant/grease inside the motor will congeal and harden with age. If 
the wiper works fine at the end of a hot day, that's a clue that you need 
to relube the motor. The wiper assembly consists of a motor,
attached to a spiral worm gear that's attached to a round toothed gear. The 
round gear drives an arm that moves the wiper shaft. On the back side of 
the round gear are 3 contact traces that rub against some
electrical "wipers" that come through the wiper case to the wire 
connectors. What the wiper and traces do is reverse the motor direction 
when the end of the track is reached.The lube/grease which aids the
gear trace/wiper hardens and lifts the electrical wiper off of the trace. 
If you open the case of the wiper (4? screws once you remove the inside 
hatch cover panel), and operate the windshield wiper, you may
see some arcing and sparking through the gear. It is sort of an opaque 
white. I am not sure if the traces are riding up and arcing when the 
circuit is opening or if the electrical wipers are shorting out to the case.
If you remove the hardened grease and replace with fresh stuff, the wiper 
will work.

The key to disassembly is to:

    1.Remove Wiper arm
    2.Remove little plastic cap
    3.Find C-clip on wiper shaft. This holds rotating wiper shaft in place
    4.Open up wiper "box" (where gears are) by removing the inside trim 
panel on the hatch, then the 4 screws
    5.Push shaft thru and remove
    6.Shaft removal allows arm removal which allows toothed gear removal
    7.Remove crappy grease
    8.Relube with white lithium grease
    9.Reassemble in reverse
   10.Enjoy smooth wiper action


Peter C. Schulz				peschulz at cisco.com
Quality Systems Engineer/SSE		http://www.cisco.com
Customer Contact Business Unit (CCBU)	Direct: 978.275.7772
Cisco Systems, Inc. 			Fax: 	978.275.5299
900 Chelmsford Street 			Pager: 	800.365.4578
Lowell, MA 01851 USA