OKIDATA OL400e Series, Service Manual

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Page: 177
Service Manual for OL400e/OL410e/OL410e-PS
Chapter 4 Failure & Repair Analysis
4.4.06 Pinch Roller Clip Problems
NOTE: The information in this section is also covered in TSB 5613 .
Symptoms
· Paper Feed Jams
· Paper jams occur at or near the registration roller.
· The leading edge of the paper (in most cases) stops under the drum unit.
· Print Registration Errors
· The printed page does not begin at the top of form.
· In some cases, the print shifts down from the top of the page.
· Print Skewing
· Printed pages may be visible skewed.
· To verify, follow this procedure.
· Load paper in the cassette.
· Take the printer OFF-LINE.
· Press PRINT FONTS.
· The Print Fonts Test will print.
· This test will dramatically show the skew, if it is present.
Cause
This problem is caused by a misalignment of the pinch roller clips on version B8 image drums.
The pinch rollers on the bottom of the drum unit provide the pressure needed to move the paper
evenly through the registration rollers. Misalignment is caused when the retaining clip slightly
rotates towards the pinch roller. The pinch roller is normally level, but a rotated clip will tilt the roller.
Because of the tilt of the pinch roller, uneven pressure will be applied to the registration roller.
(Note the space between the edge of the retaining clip and the drum's outer ribbing. Refer to the
diagram.) Rough handling during shipping may cause the retaining clips to rotate.
To identify a version B8 image drum, look at the white label on the left leading edge of the drum.
The first two characters of the drum lot number are the version.