Hitachi IJ PH Service Manual page 120

4.12.3 Repairing method for the makeup ink pump
1 Remove the tube connecting block of the makeup ink reservoir and
connect the cleaning bottle.
(You can apply pressure more easily by putting a tube between the pipe
and the cleaning bottle.)
2 Operate the pump and then MV7 on the "Solenoid Valve/Pump Test"
screen.
3 Apply pressure with the cleaning bottle.
4 When the makeup ink of the hand pump flows to the pipe M, the repair
work is completed. If the pump cannot be repaired with the cleaning
bottle, use the hand pump (refer to 4.12.2 Repairing method for the
supply pump).
Such a hard sticking as cannot be repaired with the hand pump will never
occur.
4.12.4 Procedure for repairing the circulation pump
1 Start the circulation pump by "Start up" or "Eject ink".
2 After the pump is started, operate it for about 10 minutes in the status
where the pressure adjusting knob is turned completely clockwise to
obtain the maximum pressure.
3 Stop the pump and then execute "Nozzle Backwash". If suction from the
nozzle can be confirmed, the repair work is completed. If the pump
cannot be repaired, repeat the same operations starting from (1) again.
If the pump cannot be repaired after these operations are repeated 2 or 3
times, replace the pump unit.
4.12.5 Procedure for repairing the recovery pump
1 Operate the pump, MV1, and MV6 in this order on the "Solenoid
Valve/Pump Test" screen.
2 Operate the pump in the status where the pressure adjustment knob is
turned completely clockwise to obtain the maximum pressure.
3 If ink flows to the recovery tube, the repair work is completed. If the
pump cannot be repaired after the lapse of about 10 minutes, replace the
pump unit.
Pipe
Pipe[N]
4-31
Cleaning bottle