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Service Guide ML393/ML393CPlus
Chapter 3 Maintenance
3.3.02 Printhead Gap Adjustment
General Information
Before performing this adjustment, always verify that the printhead is properly installed.
Perform the printhead gap adjustment procedure when any of the following occur.
Poor Print Quality
Uneven Print Quality (darker on one side of the document).
Excessive wear on the printhead or platen
Parts are replaced
Printhead
(3.2.01
)
Platen Assembly
(3.2.09
)
Space Motor Assembly
(3.2.14
)
Carriage Shaft
(3.2.18
)
NOTE:
Place a new ribbon cartridge in the printer before testing.
Procedure
1. Remove the printhead
(3.2.01
)
2. Remove the ribbon guide
(3.2.02
).
3. Remove the ribbon protector
(3.2.03
).
4. Install the printhead.
5. Set the printhead gap lever to position 1.
6. Set the paper release lever to the OPEN position.
7. Loosen the left and right eccentric collar setscrews.
STEP A
8. Place the printhead at the left side of the platen.
9. Rotate the left adjusting collar until you obtain a .017" (+/- .001") gap between the printhead and the
platen.
10. Place the printhead at the right side of the platen.
11. Rotate the right adjusting collar until you obtain a .017" (+/- .001") gap between the printhead and the
platen.
12. When the correct gap has been attained, tighten the left and right eccentric collar setscrews.