Action Replace the tip with a new one.
The pipettor incorrectly aspirates the liquid or liquid
drops out from the tip.
Possible cause The pipet tip is incorrectly pressed
onto the pipettor shaft.
Action Press the pipettor tip firmly.
Possible cause The shaft nut is loose (Fig. 3F).
Action Tighten the shaft nut.
Possible cause The sealing surface of the shaft is
cracked or scored.
Action Remove the tip ejector. Unscrew the
shaft nut, inspect the shaft and the
piston assembly. Replace the
damaged parts (see Section 12).
When reassembling the pipettor, the
nut should be hand tightened.
In the models 2, 10 and 20, the da-
mage of the shaft may also
cause a
damage of the piston assembly.
Replace the damaged parts (see Sec-
tion 12).
When reassembling the pipettor, the
nut should be hand tightened.
Possible cause Damage to the piston or seal due to
prolonged use with the solvents or
caustic liquids.
Action
Disassemble the pipettor as described
above. Replace the piston, seal and
O-ring (see Section 12). Rinse the
inside of the shaft in distilled water
and dry. Lubricate the seal and O-ring
with the lubricant, included with each
pipettor. Following piston replace-
ment, a calibration procedure is
required.
Note: The parts of 2 and 10
pipettor
should be lubricated evently with a
minimum amount of lubricant.
Possible cause
The pipettor is reassemled improperly.
Action Disassemble the pipettor and
reassemble it, observing the proper
sequence of steps (Fig. 3).
Possible cause No lubricant on the sealing elements.
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Action Remove the tip ejector. Unscrew the
shaft nut, remove the shaft, piston
assembly, seal and O-ring. Rinse the
removed parts in distilled water and
dry thoroughly. Lightly lubricate the
inside surfaces of the seal and the
O-ring with the included lubricant.
Reassemble the pipettor in the
reverse order.
Possible cause Contamination of the inside of the
pipettor caused by extensive aspiration
of solvents or caustic liquids or
because liquid got inside the pipettor.
Action Remove the tip ejector. Unscrew the
nut, remove the shaft, piston assembly
,
seal and O-ring. Rinse the removed
parts with distilled water and dry
thoroughly. Lightly lubricate the
inside surfaces of the seal and the
O-ring with the lubricant. Reassemble
the pipettor in the reverse order.
If you find an increase in the pipetting force, which
could happen after repetitive autoclaving of the pipettor:
Action Remove the tip ejector. Unscrew the
shaft nut, and then remove the shaft,
piston assembly, seal and O-ring.
Rinse the removed parts in distilled
water and dry. Lubricate the internal
surfaces of the seal and O-ring with
lubricant that has been included with
each pipettor. Reassemble the pipet-
tor in the opposite order.
Note: All parts of the pipettor can
be autoclaved (see Section 10).
If the problem continues after carrying out the above
steps, contact your Corning representative.
Before returning the pipettor, please ensure that the
pipettor is completely free of any chemical, radioactive or
microbiological contamination which could pose a threat
during transport and repair. As far as it is possible, clean
the pipettor.
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