Beretta L4-121 2.0L (1987)
Wiper Arm: All Technical Service Bulletins
Wiper Arm - Scratches Windshield
Number:
90-384-10
Section:
10
Date:
November 1990
Corp. Bulletin No.: 031053
Subject:
ARC SHAPED SCRATCH IN WINDSHIELD FROM WIPER ARM RAMP FINGER
Model and Year:
1987-90 CORSICA/BERETTA
FIGURE 1
TO:
ALL CHEVROLET DEALERS
Some Corsica/Beretta models have been diagnosed as having arc shaped scratch marks on the right side of the windshield. The scratches are caused by
the wiper arm ramp finger rubbing on the windshield.
The ramp finger rubbing on the windshield is caused by opening the hood assembly far enough to contact the right wiper arm assembly. This slightly
deforms the wiper blade superstructure which in turn allows the ramp finger to contact the glass and scratch the surface. After VIN breakpoints
LY147121 (Wilmington) and LE165062 (Linden), wiper arms used in production have the ramp finger reduced from 16 to 10 mm, refer to Figure
1.
This change will reduce the incident rate, however, if enough deformation exists the ramp finger may still contact the glass.
To stop the ramp finger from contacting the windshield, perform the following:
Remove right hand wiper arm and grind down ramp finger to 10 mm (0.4 in.) (be sure to round off ramp finger to eliminate sharp edges).
Remove suspect wiper blade superstructure.
Place wiping element on clean flat surface.
Apply 6.12 N (22 oz.) force at center of wiper blade superstructure - near pin connection (to simulate wiper arm load).