Cleaning - HP 7901A Operating And Service Manual

Maintenance
5-14. CLEANING
5-15. Cleaning should be performed bi-monthly, or
when an inspection discloses disc drive contamination.
Cleaning materials include Kimwipe tissues and a filtered
solution of 91 percent isopropyl alcohol mixed with 9
percent distilled or deionized water by volume (HP part
number 8500-0559). The following description includes
cleaning procedures for the read/write heads, carriage rails
and bearings, encoder plate, front door filter, front door
assembly, spindle and linear motor, and the casting and
cartridge receiver.
CAUTION
Always use Kimwipe tissues (Type 900-S)
and the recommended cleaning solution.
Do not substitute. Many other tissues
contain contaminating oils, and other
solutions might contain impurities. Oil
residue or solution impurities can cause
disc dri ve damage.
5-16. READ/WRITE HEADS. Equipment required to
clean the read/write heads include Kimwipe tissues, the
recommended cleaning solution (refer to paragraph 5-15), a
cleaning tool and an inspection mirror. To clean the heads,
proceed as follows:
a. Press the LOAD switch to the released position.
Remove the disc cartridge. Remove drive power by
setting the POWER switch off.
b. Remove the disc drive top cover and cartridge receiver
and install the head installation tools.
c. Fold one Kimwipe tissue (Type 900-S) into a rectangle
(approximately 1 by 5 inches) and wrap it over the
rounded edge of the head cleaning tool. A rubber band
can be used to secure the Kimwipe to the tool for ease
of handling. (See figure 5-1.)
d. Dampen (do not saturate) the Kimwipe with the
isopropyl alcohol solution, part no. 8500-0559.
I
CAUTION
I
In making finger contact with the head
and head assembly, note that the head
shoes are mounted on fragile gimbals.
Excessive force can cause damage to the
heads.
e. Clean the heads by placing the tissue-covered tool
between the head pin and gently wiping the head
surfaces. Use the inspection mirror to confirm that all
signs of oxide contamination are removed.
f. When the heads have been cleaned, remove all cleaning
tools and replace cartridge receiver, and disc drive top
cover.
g. Restore the disc drive to operational status.
5-4
7900-151A
TOOL
RUBBER
BAND
fI/
/
FOLDED
\ - - - - KIMWIPE
Figure 5-1. Prepared Head Cleaning Tool
7901A
5-17. CARRIAGE RAILS AND BEARINGS. The
required cleaning materials for the carriage rails and
bearings include Kimwipe tissues and isopropyl alcohol
solution. Some amount of lubricant on the rails is allow-
able. Clean only when surface particles have accumulated.
To clean the carriage rails and bearings proceed as follows:
a. Set the LOAD switch to the released position. Remove
the disc cartridge. Remove drive power by setting the
POWER switch off.
b. Remove the disc drive top cover and cartridge receiver.
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CAUTION
I
Care must be taken not to saturate
bearings. Excessive alcohol might damage
the lubrication pack.
c. Dampen the Kimwipe tissue with alcohol and clean
carriage rails and bearing outer-wear surfaces.
d. Replace the cartridge receiver and disc drive top cover.
e. Restore the disc drive to operational status.
5-18. ENCODER PLATE. The required encoder plate
cleaning materials include Kimwipe tissues and isopropyl
slcohol solution. To clean the encoder plate proceed as
follows:
a. Set the LOAD switch to the released position. Remove
the disc cartridge. Remove drive power by setting the
POWER switch off.