Sharp R-84ST Service Manual page 29

COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE
1. CARRY OUT 3D CHECKS.
2. Disconnect the H.V. wire B and filament lead of the
transformer from the magnetron.
3. Remove the one (1) screw holding the chassis support to
the magnetron.
4. Move the air intake duct to left.
5. Carefully remove four (4) screws holding magnetron to
waveguide, when removing the screws hold the
magnetron to prevent it from falling.
REMOVAL
1. CARRY OUT 3D CHECKS.
2. Remove the one (1) screw holding the noise filter to the
chassis support.
3. Release the noise filter from the tabs of the fan duct.
4. Disconnect the wire leads from the fan duct.
5. Remove the one (1) screw holding the capacitor holder
to the oven cavity back plate.
6. Release the tabs of the capacitor holder from the fan
duct.
7. Remove the one (1) screw holding the fan duct to the
oven cavity back plate.
8. Remove the fan duct from the oven.
9. Remove the fan duct from the fan motor shaft according
the following procedure.
1) Hold the edge of the rotor of the fan motor by using
a pair of groove joint pliers.
CAUTION:
• Make sure that no swarf from the rotor enters
the gap between the rotor & stator of the fan
motor.
• Avoid touching the coil of the fan motor with
the pliers as the coil may become cut or
damaged.
• Avoid deforming the bracket whilst using the
pliers.
2) Remove the fan blade assembly from the shaft of the
fan motor by pulling and rotating the fan blade with
your hand.
3) Now, the fan blade is free.
CAUTION:
• Do not reuse the removed fan blade as the
fixing hole may be oversize.
10. Remove the two (2) screws and nuts holding the fan
motor to the fan duct.
11. Now, the fan motor is free.
Coil
Groove joint pliers
Stator
Gap
Bracket
Rotor
Rear view
MAGNETRON REMOVAL
6. Remove the magnetron from the waveguide with care so
the magnetron antenna is not hit by any metal object
around the antenna.
CAUTION: WHEN REPLACING THE MAGNETRON,
FAN MOTOR REPLACEMENT
INSTALLATION
1. Install the fan motor to the fan duct with the two (2)
screws.
2. Install the fan blade to the fan motor shaft according the
following procedure.
1) Hold the centre of the bracket which supports the shaft
of the fan motor on the flat table.
2) Apply the screw lock tight into the hole (for shaft) of the
fan blade.
3) Install the fan blade to the shaft of fan motor by pushing
the fan blade with a small, light weight, ball peen
hammer or rubber mallet.
CAUTION:
•
•
•
3. Install the fan duct to the oven cavity back plate with the
one (1) screw.
4. Insert the tabs of the capacitor holder to the fan duct.
5. Install the capacitor holder to the oven cavity back plate
with the one (1) screw.
6. Install the noise filter to the fan duct and the chassis
support with the one (1) screw.
7. Re-connect the wire leads to the fan motor.
Shaft
These are the position
where should be
Axis
pinched with pliers
Stator
Rotor
Side view
R-84ST -
29
BE SURE THE R.F. GASKET IS IN PLACE
AND THE MAGNETRON MOUNTING
SCREWS ARE TIGHTENED SECURELY.
Do not hit the fan blade strongly when installed
because the bracket may be deformed.
Make sure that the fan blade rotates smoothly
after installed.
Make sure that the axis of the shaft is not
slanted.
Table
Shaft
Center of
bracket